Vised Manual

MCNP Visual Editor Computer Code Manual For Vised Version 19K

Released November, 2005 L.L. Carter and R.A. Schwarz

For the latest information visit WWW.MCNPVISED.COM

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Table of Contents 1.0 INTRODUCTION .................................................................................................................... 5

1.1 INSTALLATION NOTES................................................................................................ 6 1.2 PROGRAM BACKGROUND........................................................................................... 6

2.0 BEGINNING AN INTERACTIVE EDITING SESSION....................................................... 7

2.1 IMPORTANT FILES IN THE VISUAL EDITOR ............................................................... 9 2.2 THE MAIN MENU FUNCTIONS ................................................................................. 10 2.3 READING AND WRITING THE INPUT FILE ................................................................ 10

3.0 FILE OPTIONS .................................................................................................................... 12

4.0 THE INPUT WINDOW ........................................................................................................ 12

5.0 PLOTTING AND CHANGING PLOT PARAMETERS...................................................... 13

5.1 UPDATE .................................................................................................................. 14 5.2 LAST BUTTON......................................................................................................... 14 5.3 ZOOM CHECK BOX.................................................................................................. 14 5.4 ORIGIN CHECK BOX................................................................................................ 14 5.5 CHANGING THE EXTENTS........................................................................................ 15 5.6 REFRESH CHECK BOX............................................................................................. 15 5.7 THE SURFACE AND CELL CHECK BOX .................................................................... 15 5.8 COLOR CHECK BOX ................................................................................................ 15 5.9 FACETS CHECK BOX ............................................................................................... 15 5.10 WW MESH CHECK BOX ....................................................................................... 16 5.11 RECT CHECK BOX................................................................................................. 16 5.12 TAL MESH CHECK BOX ........................................................................................ 16 5.13 PLOT ROTATION OPTIONS..................................................................................... 16 5.14 SCALES CHECK BOX ............................................................................................. 16 5.15 RES TEXT BOX...................................................................................................... 16 5.16 PSCRIPT CHECK BOX ............................................................................................ 16 5.17 CHANGING THE BASIS........................................................................................... 16 5.18 VIEWING GLOBAL/LOCAL COORDINATES............................................................. 17 5.19 SETTING CELL LABELS ......................................................................................... 17 5.20 LEVEL PULLDOWN MENU ..................................................................................... 17

6.0 THE SURFACE WINDOW .................................................................................................. 18

6.1 CREATING A SURFACE ............................................................................................ 18 6.2 SCANNING A SURFACE ............................................................................................ 19 6.3 DELETING A SURFACE............................................................................................. 19 6.4 EDITING A SURFACE................................................................................................ 19 6.5 HIDING AND SHOWING SURFACES........................................................................... 19 6.6 SURFACE COMMENTS.............................................................................................. 19 6.7 ENTERING SURFACE DIMENSIONS IN INCHES .......................................................... 19 6.8 SURFACE DISTANCE................................................................................................ 20 6.9 SURFACE DELTA ..................................................................................................... 20 6.10 MACROBODY SURFACES....................................................................................... 20

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6.11 THE SURFACE WIZARD ......................................................................................... 21

7.0 THE CELL WINDOW .......................................................................................................... 22

7.1 CREATING A CELL.................................................................................................. 22 7.2 DISCUSSION OF CELL PASTE AND CUT OPERATIONS.............................................. 23 7.3 SPECIAL SENSE CONSIDERATIONS .......................................................................... 25 7.4 CREATING A CELL WITH UNIVERSES....................................................................... 25 7.5 USING UNDO........................................................................................................... 26 7.6 REGISTER................................................................................................................ 26 7.7 SCANNING A CELL .................................................................................................. 26 7.8 DELETING A CELL................................................................................................... 26 7.9 EDITING A CELL...................................................................................................... 26 7.10 CREATE LIKE......................................................................................................... 27 7.11 HIDING AND SHOWING CELLS............................................................................... 27 7.12 CELL COMMENTS.................................................................................................. 27 7.13 SPLITTING A CELL ................................................................................................. 28 7.15 CREATING A SQUARE LATTICE .............................................................................. 30 7.16 CREATING A HEXAGONAL LATTICE ....................................................................... 31 7.17 SPECIAL HEX LATTICE DISPLAY OPTIONS ............................................................ 32 7.18 THE CELL WIZARD ............................................................................................... 32

8.0 MATERIALS......................................................................................................................... 37

8.1 CREATING A MATERIAL .......................................................................................... 37 8.2 SCANNING A MATERIAL.......................................................................................... 38 8.3 DELETE A MATERIAL .............................................................................................. 38 8.4 EDIT A MATERIAL................................................................................................... 38 8.5 THE VISED.DEFAULTS FILE ..................................................................................... 38 8.6 MATERIAL LIBRARY ............................................................................................... 40 8.7 MATERIAL OPTIONS................................................................................................ 41

9.0 IMPORTANCES ................................................................................................................... 41

9.1 SETTING CELL IMPORTANCES ................................................................................. 41 9.2 USING A SCALE FACTOR ......................................................................................... 41 9.3 USING A GEOMETRIC FACTOR................................................................................. 42 9.4 THE IMPORTANCE DISPLAY .................................................................................... 42 9.5 TRUNCATING IMPORTANCES ................................................................................... 42

10.0 TRANSFORMATIONS ...................................................................................................... 43

11.0 RENUMBER CELLS/SURFACES..................................................................................... 44

12.0 RUN ..................................................................................................................................... 45

13.0 PARTICLE DISPLAY......................................................................................................... 46

13.1 SDEF SOURCE PLOTTING ..................................................................................... 47 13.2 KCODE SOURCE PLOTTING ................................................................................. 47 13.3 PARTICLE TRACK PLOTTING ................................................................................. 48 13.4 SETTING POINT COLOR AND SIZE.......................................................................... 48 13.5 SETTING ENERGY OR WEIGHT RANGES ................................................................ 48

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13.6 PROBLEMS GENERATING PARTICLE TRACKS ........................................................ 49

14.0 TALLY PLOTS ................................................................................................................... 50

15.0 CROSS SECTION PLOTS.................................................................................................. 51

16.0 3D RAY TRACED IMAGE ................................................................................................ 52

16.1 3D COLOR PLOTS ................................................................................................. 53 16.2 3D UPDATE THE PLOT BASIS ................................................................................ 53 16.3 COLOR BY CELL/SURFACE .................................................................................... 53 16.4 DRAW LINES AROUND CELLS ............................................................................... 53 16.5 COLOR CELLS BY MATERIAL ................................................................................ 53 16.6 3D SHADING......................................................................................................... 54 16.7 DISTANCE SHADING.............................................................................................. 54 16.8 POINT/PLANE SOURCE TYPE ................................................................................. 54 16.9 SHOW THE PLOT PLANE ........................................................................................ 54 16.10 HIDE/SHOW COOKIE CUTTERS............................................................................ 54 16.11 PLOT TO THE OUTSIDE WORLD/PLOT PLANE ...................................................... 54 16.12 PLOT RESOLUTION.............................................................................................. 54 16.13 3D RADIOGRAPHIC PLOTS .................................................................................. 55 16.14 3D TRANSPARENT PLOTS ................................................................................... 55

17.0 DYNAMIC 3D DISPLAY................................................................................................... 55

18.0 CAD IMPORT..................................................................................................................... 57

18.1 2D CAD IMPORT ................................................................................................... 57 18.2 3D CAD IMPORT .................................................................................................. 60 18.3 CONSTRAINTS/RESTRICTIONS FOR 3D CAD CONVERSION ................................... 62 18.4 USING CAD AS A GRAPHICAL USER INTERFACE FOR MCNP WITH PERIMETER MODELING..................................................................................................................... 63 18.5 3D DISPLAY OF IMPORTED CAD FILES ................................................................ 63 18.6 CONVERSION OF LARGE FILES .............................................................................. 65

19.0 READ AGAIN..................................................................................................................... 66

20.0 BACKUP INP...................................................................................................................... 67

21.0 PROBLEM REPORTING ................................................................................................... 67

22.0 REFERENCES .................................................................................................................... 67

APPENDIX A............................................................................................................................... 69

APPENDIX B ............................................................................................................................... 90

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1.0 Introduction The Monte Carlo N-Particle (MCNP) computer code is a particle transport code with powerful three dimensional geometry and source modeling capabilities that can be applied to reactor physics, shielding, criticality, environmental nuclear waste cleanup, medical imaging, and numerous other related areas. Creating a MCNP input file with a line editor is both tedious and error prone as it entails arduous descriptions of geometry, tallies, sources, and optimization parameters. These input files may contain thousands of lines, and once the input file is created, substantial additional time is often required to plot and test the geometry and to correct any errors. The Visual Editor (References 1-7) was developed to assist the user in the creation of MCNP input files. While the initial motivation in the development of the Visual Editor was for the creation of input files, its other uses as a graphical user interface to MCNP may be even more important to a typical user than the creation of input files. These powerful features include: ♦ Two side-by-side 2-D plots of the geometry.

♦ Capability to plot source points to verify the MCNP source. ♦ Optional 3-D views using either ray tracing or dynamic wire mesh displays. ♦ Capability to dynamically build a geometry while viewing it as it evolves. ♦ Optional manual editing of the input file and immediate re-initialization with the

changes showing up in the plots. ♦ Dynamic input of materials, transformations, and importances (using the mouse). ♦ Dynamic displays of particle tracks, cross sections, and tallies. ♦ A surface wizard to optionally assist the user in creating (and visually being able to

see the surface types) surfaces. ♦ A cell wizard to assist the user in creating cells. ♦ Optional import and conversions of a CAD file to an MCNP input file.

Work on the Visual Editor started around 1992. The first release to RSICC was in 1997. The Visual Editor code became part of the MCNP package with the release of version 5 of MCNP. The Visual Editor allows the user to easily set up and modify the view of the MCNP geometry and to determine model information directly from the plot window. The Visual Editor also allows the user to interactively create an input file with the help of two or more dynamic cross sectional views of the model. A wide selection of menu options enables rapid input of information and immediate visualization of the geometry and other information being created. The current version of the Visual Editor runs on either Windows or Linux platforms. The new user should practice with a few simple problems before trying to create an involved geometry. An example exercise is given in Appendix A showing detailed steps, with graphical displays -- if this is a first time use of the Visual Editor you should read

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Sections 1.1, 1.2, and 2.0 before doing the example in Appendix A. Such examples also aid in understanding the basics of the reading in and saving of MCNP input files, the plotting of the geometry in the two plot windows, etc. The following discussion summarizes how to use the graphical interface. The Visual Editor is constructed with user-friendly menu buttons so this manual is primarily to help the new user get started and to provide some detail when specific questions arise. The discussion here assumes that the user has some familiarity with the MCNP geometry specification, as described in the MCNP manual. Additional information on the Visual Editor, including training opportunities can be found at the Visual Editor website (www.mcnpvised.com). Users are encouraged to take a training class since so many different aspects are involved in fully utilizing the Visual Editor. The contents of this manual is also contained in the Visual Editor help package, and can be accessed by selecting “Help->Help Topics” from the main menu. The help package contains a table of contents and is searchable. Additionally, each of the individual windows has a help button that will take the user to the appropriate section of the help package. 1.1 Installation Notes For many applications, the Visual Editor executable can be used as distributed. If you want to do particle track plotting, cross section plotting, or run MCNP inside the Visual Editor, the xsdir file must be in the same directory as the Visual Editor executable or a path to xsdir must be specified on the system as required for running MCNP. If binary cross section files are involved, they must be compatible with the current version of the Visual Editor, or else you should switch to ASCII cross section files. To access the material libraries, the code will try to use the default environment variable to read the libraries from the installed location. If this fails, you need to create a “vised.defaults” file for the configuration of MCNP on your system. See the section on materials for more information on how to do this. This creation of a “vised.defaults” file is usually a good thing to do for flexibility and to keep things parallel with your use of MCNP. 1.2 Program Background The size of the fonts used by the windows is fixed and cannot be changed. The font used is called “ariel 7”. If the Visual Editor windows appear too large for your screen, it is recommended that you increase your screen resolution. The ideal screen resolution is 1280x1024.

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The development of the Windows Visual Editor utilized a Windows 2000 platform. For best performance, it is recommended that users run the Visual Editor in Windows 2000 or Windows XP. Table 1.1 below lists the different operating systems and what is known about its compatibility with the Visual Editor. If an operating system is not listed, than the code has not been tested on that platform and its functionality is not known.

Table 1.1. Operating System Compatibility. Operating System

Compatibility

Windows 2000 Most compatible, this is the Visual Editor development platform. Windows XP Very compatible with 2000 version and should be just as stable. Windows NT Somewhat unstable, not recommended. Windows 98 Very unstable, not recommended. Windows 95 Very unstable, not recommended. 2.0 Beginning An Interactive Editing Session Use Windows explorer to bring up the Visual Editor. Figure 2.1 shows a view of the initial screen. Notice that the main menu functions are shown across the top and that each plot window has its own set of plot commands. You can read in an input file by using the “File->Open” command (which will reformat the input file) or the “File->Open (do not modify input) command, which will not change the input file.

Figure 2.1. Startup configuration for the Visual Editor.

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To create a new geometry, you create surfaces by selecting “Surface” from the main menu and following the instructions beginning in Section 6.0 for the surface window – even experienced users may find it convenient to just use the surface wizard discussed in Section 6.11 to create new surfaces. These surfaces can then be used to create cells, by selecting “Cell” from the main menu and following the instructions beginning in Section 7.0 for the cell window. A Cell Wizard, discussed in section 7.18, is also available to aid in the creation of cells. The input window, shown at the bottom of Figure 2.1, can be displayed by selecting “Input” from the main menu. In the input window, a title card indicating the creation date is created by default when starting from scratch and not reading in an input file. If you want to add you own title, enter it above this card, then select “Save-Update” from the menu. This will temporarily cause the line containing the creation date to go away, but it will come back as a comment card after the first cell is created. You can edit the file in the input window and then select the “Save-Update” menu option to update the plots to reflect the changes made. This gives you the freedom to work either in editor mode or use the graphical interface commands. If the file is modified by hand in such a way that it is no longer valid, it is possible when doing “Save-Update”, that the Fortran will generate a fatal error causing the Visual Editor to terminate, although an attempt is made to trap most fatal errors. When doing a “Save – Update” command, the Visual Editor writes out the input to a temporary file name called inpn. When you are ready to save the file to a permanent file, use the “File->Save” command or the “File->SaveAs” command. The Visual Editor will automatically back up the file every five minutes to a file called “inpn.sav”, so if the Visual Editor crashes, you will not lose more than 5 minutes of work. Also, if the Visual Editor encounters a MCNP fatal error that it can not recover from, it will try to save the input into a file called “inpcrash”. Error and information messages are sent to the text window that is located under the main menu.

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2.1 Important Files In The Visual Editor Table 2.1 shows a list of the files used by the Visual Editor. The Visual Editor prints out a number of auxiliary files. Because of this, you may want to run the Visual Editor in its own directory and transfer the input files you are creating or working on to that directory.

Table 2.1. Files used by the Visual Editor. File Name Description inp Used by the Visual Editor as the default input file name. This file is

overwritten each time the editor starts up. The Visual Editor will give unpredictable results if you try to read this file in as the input file.

inpn Inpn is the file that is created when doing a “Save-Update” command in the input window. The Visual Editor will give unpredictable results if you try to read this file in as the input file.

inpn1, inpn2, inpn3, …

By selecting “backup” from the main menu a new inpn? (inpn1, inpn2, inpn3, …) file is created representing the contents of the current file being worked on.

inpn.sav The input file is backed up every 5 minutes to this file, so if the system crashes you will not lose more than 5 minutes of work. The Visual Editor will give unpredictable results if you try to read this file in as the input file.

inpcrash If MCNP generates a fatal error that results in a “stop” statement, a message is sent to the Visual Editor telling the user that the code is about to terminate. It then saves the current input file into a file called inpcrash. This will allow the user to get the file that was generated up to the point of the fatal error. The Visual Editor will give unpredictable results if you try to read this file in as the input file.

outp, outq, … In normal plotting mode, the outp file is overwritten and does not sequentially increase. In other modes, such as 3D plotting, particle track plotting, tally plotting and running, the outp file name increases sequentially just like when running MCNP outside the Visual Editor. If the Visual Editor crashes, always check this file to see if there are fatal MCNP errors not trapped by the Visual Editor.

inpt Temporary file used for 3D plotting and collision point plotting. outp3d Output file for 3D plotting. outmc Contains MCNP output messages, normally written to standard out. If the

Visual Editor crashes, always check this file to see if there are fatal MCNP errors not trapped by the Visual Editor.

vised.defaults The file containing the location of xsdir and the material libraries, this file is needed for using the material libraries and for selecting isotopes when creating materials. See Section 8.5.

stndrd.n Standard material file containing neutron cross sections available for all users. stndrd.p Standard material file containing photon cross sections available for all users. usr.n User specific material file containing neutron cross sections for the individual

user. usr.p User specific material file containing photon cross sections for the individual

user.

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2.2 The Main Menu Functions Table 2.2 provides an overview of the main menu options and their purpose.

Table 2.2. Main Menu Options. Menu Option Description File Used to open and save MCNP input files. File-> New View is used to open

additional plot windows into the geometry. Input Used to bring up a simple text editor containing the complete contents of the

input file, including cards not recognized by the Visual Editor. The input file can be edited by hand in this window.

Update Plots Update both plot windows. Surface Bring up the surface window to scan, create or modify surfaces. Cell Bring up the cell window to scan, create or modify cells. Data Menu for some data cards: materials, importances, transformations. Run Enable the running of MCNP input files. Particle Display Bring up the source window that allows for source point display and particle

track plotting. Tally Plots Allow the plotting of tallies from a runtpe or mctal files. This is the same

capability that currently exists when requesting MCPLOT (mcnp inp=filename z options)

Cross Section Plots

Allow the plotting of MCNP cross sections. This is the same capability that currently exists when requesting MCPLOT (mcnp inp=filename ixz options)

3D View Allows the rendering of a 3D view of the geometry or a radiographic image using ray tracing, or select “Dynamic 3D Display” to obtain a dynamic wire mesh display in some current versions of the Visual Editor.

CAD Import Import a CAD 2D dxf or 3D sat file. Read_again Update the plots after the file that was read in has been modified by an

external text editor. This allows the user to edit the file outside the Visual Editor and only use the Visual Editor to plot the geometry.

Backup Creates a backup file that sequentially increases (inpn1, inpn2, …). View Select the active plot window. Help Shows the version number, along with access to this manual in electronic

form, including an index and search ability. 2.3 Reading and Writing the Input File The attempt is made to read the MCNP input file and write out the same information to the inpn file. If the input file is created outside the Visual Editor, you will find that when you save it, the Visual Editor will change the order of the lines in the input file. If the user does not want the Visual Editor to change the input file, they can open up the input file with the File->Open(do not modify input) option. However, in this mode the creation capabilities of the Visual Editor are disabled and the Visual Editor is only used for plotting.

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Below is the order in which the Visual Editor writes out the input file:

1. Title card 2. Cell Cards 3. blank line 4. Surface Cards 5. blank line 6. Transformations 7. Mode 8. Source 9. Materials 10. Importances 11. Other data [VOL, PWT, EXT, FCL, PD, DXC, NONU, WWN, TMP] 12. Data not recognized by the Visual Editor

The editor does it best to keep the original comments in the proper locations. The "$" comments from the inp file for cell and surface cards are read into the Visual Editor, but only one "$" comment will be written out for a cell or surface card; i.e., if there are more than one "$" comments for a given cell or surface, only the first one will be written to the inpn file. The Visual Editor will print out an error message saying the “$ comment is lost.” There are a number of data cards that are still not individually recognized by the Visual Editor such as the source and tally cards. These are stored in a temporary file and written back out to the input file when it is saved. All cards that are individually recognized by the Visual Editor will be formatted to its specific style. For example importances are written out in a special format that uses a "$" comment on each line to show the cell numbers involved for that line. The Visual Editor also does not currently allow the cell parameters to be specified on the cell card, it will strip off the cell card parameters and place them in a data block. To avoid this problem, the input file can be read in without modification with the “File->Open (do not modify input)” option or by using the “Read Again” option

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3.0 File Options The file menu has a number of typical options available in Windows applications, however, there are a few Visual Editor specific options. File->New View will open up a new plot window with the plot parameters set to default values. File->Open will bring up a file selection window that will allow a new MCNP input file to be read in. A file opened in with this command will be re-formatted by the Visual Editor to enable the creation capabilities. File->Open (do not modify input) will bring up a file selection window that will allow a new MCNP input file to be read in. A file opened in with this command will not be modified and all creation capabilities (surface, cell, materials, etc.) will be turned off. However, all plotting capabilities will still be available including 2D plots, 3D plots and particle plots. The input can also be opened up in an external text editor and the plots can be updated by using the “Read_again” menu option. File->Clear Input will clear the active input file, so the user can start over from scratch. This removes all surface, cell and MCNP data information. File->Save and File->Save As must be used to save the current input file that is being generated. If you leave the Visual Editor before saving the file, all the information currently in memory will be lost. 4.0 The Input Window To bring up the input window, select Input from the main menu. This will bring up a text window that shows the entire contents of the input file. If an input file has not yet been read in, it will show a single default comment card indicating the current date. As surfaces and cells are created, they will show up in this input window. At any time, the user can type any valid MCNP data into the input window and then select “Save-Update” to reset the Fortran memory and update the plots. This gives the user the freedom to work either with the Visual Editor interface tools or to work in text mode. The Visual Editor does not individually handle all MCNP data cards at this time. Data cards individually recognized by the Visual Editor are cells, surfaces, materials, importances, and transformation. Data cards that are not individually recognized by the Visual Editor are read in from an input file, and are copied directly over into the input window. Currently, the only way to change these data cards is to change them by hand in the input window and then select “Save-Update” to update the Fortran memory with the modifications that have been made. It is important to note that doing a “Save-Update” in the input window, saves the file out to a temporary file called “inpn”. The user must select File->Save or File->Save As to save the file to permanent storage.

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5.0 Plotting And Changing Plot Parameters The Visual Editor starts up with two default plot windows. Additional plot windows can be created by selecting File->New View. Figure 5.1 shows an expanded view of a Visual Editor plot window and the various plotting options available on the top and side of the plot window. Also shown is the menu that is displayed when you right click in the plot window. The top portion of this menu can be used to change some of the plot parameters. Also, included in this menu are some shortcuts to common surface and cell operations. To print out a hard copy of a plot, select “File->Print” from the main menu and it will send the contents of the currently selected window to the printer. To include plots in a document, right click in the plot window and select the “send to clipboard” option. Then go into the text document and select paste to paste.

Figure 5.1. Plot Window Options.

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5.1 Update As it's name implies, the "Update" button is used to redraw the plot for that window. To update all plots, use the “Update plots” main menu option. You typically use the “Update plots” button to create the plots after reading in a new input file. This is not done automatically because there are times when you do not want the plot to be displayed because it would take too long to generate. When you change the basis, origin, or extent parameters by hand, you need to select “Update” in the specific window or "Update plots" from the main menu to redraw the plots with the new plot values. 5.2 Last Button The "Last" button enables you to go back to prior plots. For instance, if you use the “Zoom” button to zoom in on a region in the geometry, the last button will take you back to the “Unzoomed” view. All of the plot parameters are saved when the plot is changed and "Last" will go backwards through the sequence of plots. The parameters changed by "Origin", "Zoom" and "Basis" can all be recalled with "Last". Last remembers the last 1000 plots made for each plot window. 5.3 Zoom Check Box The "Zoom" check box enables the user to magnify a portion of the plot. When the "Zoom" check box is selected, the user can drag the mouse across a portion of the geometry and that area will be magnified. This is useful for intricate work in small cells. The Visual Editor stays in zoom mode until you uncheck the “Zoom” check box. This allows for multiple zoom operations to be done in a row. Sometimes it is useful to click zoom on one plot and then drag the mouse across a zoom area in a different plot. The identified area will then be shown in the original plot window. 5.4 Origin Check Box The origin is the center of the plot. The origin of the two plots automatically defaults to 0,0,0. These coordinates can be set by hand by entering the desired origin values in the three text boxes below the “Origin” check box. Once the new origin is ready to be implemented, select "Update plots". Another way to adjust the origin involves selecting the "Origin" check box for the plot and then setting the origin by clicking in the plot to define the location for the new center of the plot. The origin can be set in either plot window. The plot will stay in “origin” mode until the origin check box is clicked again to turn it off. The buttons to the left of the origin values, enable the user to change the origin “x”, “y” or “z” value by clicking on the coordinate to be changed and selecting its value with a

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click of the mouse from one of the plot windows. For example, if the right plot is an xy view and the left plot is an xz view, you can change the elevation of the xy view by clicking the z box for the right plot and then clicking the at a different z value on the left plot. The z for the right plot will change to that selected value, resulting in a different cross sectional view. 5.5 Changing the Extents The horizontal extent is the distance from the center of the plot to a horizontal edge of the plot. The vertical extent is the distance from the center of the plot to the top/bottom of the plot. The extents for the plots automatically default to 100. The extents can be changed by typing in desired extents under the “Extent” label and selecting “Update” or by using the slider bar on top of the plot windows. This modifies the extent by a scale factor between 0.1 and 10. You can also click on the left/right side of the slider bar handle to increase/decrease the extents by about 10% for each click. The buttons to the left of the extent values, allow the user to square up the extents. This is often used after “zooming” in on a region. Both extents will be set to the value you click on making them equal. 5.6 Refresh Check Box This check box defaults to the checked “on” position. Turn this check box off if you do not want to update the plot window when cells or surfaces are modified or when “Update Plots” is selected from the main menu. There are times when you may not want to update a particular plot window. For example, you might want to turn off plotting if the view contains a large lattice that is time consuming to plot. Be careful when you use this check box to turn off plotting, since the plot will not be updated until you turn this check box on again. 5.7 The Surface and Cell Check Box When the "Surface" check box is turned on, surface numbers will appear on the plots next to their respective surface. If the check box is turned off, surface numbers do not appear. Next to the surface check box is a text box where you can enter the font size to use for the surface label. Increase this number to increase the label size When the "Cell" check box is turned on, cell numbers will appear inside the cells. The meaning of the “cell” number is determined by the cell label that has been selected. As with surface numbers, the size of the font used for cell numbers can be changed by changing the number in the text box. 5.8 Color Check Box This check box will enable color plotting. The color can be set to represent Materials or any of the items specified by the “color by” option, as shown in Figure 5.1. 5.9 Facets Check Box When displaying macrobody surfaces, this check box will change the display to include the surface facet number when a macrobody surface is involved.

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5.10 WW Mesh Check Box By checking this check box, the weight window mesh will be displayed if this option is used in the active input file. 5.11 Rect Check Box Select this check box to change the plot window to a rectangular plot instead of a square plot. A rectangular plot is needed to see the grid lines or the plot legend. Tally and cross section plots also look better in a rectangular plot instead of a square plot. 5.12 Tal Mesh Check Box By checking this check box, the tally mesh will be displayed if the input file contains a tally mesh. 5.13 Plot Rotation Options The 2D plots can be rotated through three different angles. Selecting “Axial” will rotate the plot in a counter clockwise direction around the axial axis pointing out of the plot window. The default rotation angle is 15 degrees. The “Vert” option will rotate the 2D view along the angle between the horizontal and axial vector. This will cause the view to rotate around the vertical axis. The “Horiz” option will rotate the 2D view along the angle between the vertical and axial vector. This will cause the view to rotate around the horizontal axis. 5.14 Scales Check Box The “Scales” pull down menu allows you to display a border around the geometry plot or a grid across the plot. This can only be seen if the “Rect” check box has been set. 5.15 Res Text Box The resolution text box sets the resolution for color plots. The default value is 300. The maximum value is 3000. The higher the resolution, the better the color resolution on a color plot. The drawing time will increase as this value increases. 5.16 Pscript Check Box When this checkbox is selected, a postscript file is written to the out.ps file when the current active plot when it is updated. This works for general geometry plots, particle collision plots and 3D plots. 5.17 Changing the Basis One of the advantages of multiple plots is the ability to view the same geometry with multiple cross sectional slices. This is especially helpful with complex three-dimensional geometries. The first three text entries of the basis represent the horizontal axis vector of the plot and the lower three text entries of the basis represent the vertical axis vector of the plot. The text entries can be changed by hand and the plot will be updated to the indicated basis vectors by selecting the “Update” button or “Update Plots” menu option to redraw the plots. The left plot in the Editor defaults to an xz basis and the right

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defaults to a xy basis. A "Basis" pull down menu is available in the top left portion of the plot window with the choices of xy, xz, yx, yz, zx, and zy. The basis menu is also available by clicking the right button in the plot window. The basis can also be entered by hand by setting the six basis vectors and then selecting the “Update” button or “Update Plots” menu option to redraw the plots. The code will normalize each basis vector and adjust them, if necessary, to be normal. 5.18 Viewing Global/Local Coordinates The Global/local menu determines how the displayed coordinates at the top of the plot window are to be interpreted. With local set, the coordinates are for the universe prior to being transformed because of a transformation or a fill, otherwise the coordinates are relative to the origin of the geometry. 5.19 Setting Cell Labels Selecting the "Labels" button with the right mouse button will bring up menu which lists the cell labels recognized by MCNP. These labels are: CEL, IMP:, RHO, DEN, VOL, FCL:, MAS, PWT, MAT, TMPn, WWNn:, EXT:p, PD, DXC:, U, LAT, FILL, and NONU. Those items with a ":" have a pull right menu to choose p, n, e. Items with an “n” in their name require that you enter the requested value at the top of the plot window in the “n =” text box. 5.20 Level Pulldown Menu The level pulldown menu allows you to hide lower levels of a lattice for complex geometries that have lattices inside of lattices, such as a reactor core filled with fuel assemblies. The geometry will only be plotted to the level specified. Level 1 is the top level, normal geometries will plot at this level. Level 3 will go down one universe level, level 5 will go down two universe levels. By setting these level buttons, you can significantly decrease the amount of time it takes to make a plot of a lattice geometry by suppressing the plotting of lower universe information. Additionally, you can use the special lattice cell label options to plot useful information about the lattice geometry.

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6.0 The Surface Window Figure 6.1 shows the surface window. This window is used to create new surfaces, delete surfaces and modify surfaces. The operation that is being performed is determined by the mode shown at the top of the surface window. The default mode is “Create new” which will create a new surface -- even experienced users may find it convenient to just use the surface wizard discussed in Section 6.11 to create new surfaces. All recognized MCNP surface types can be created or modified.

Figure 6.1. The surface window.

6.1 Creating a Surface To create a new surface, first select a surface type, either by clicking on the “Surfaces” menu option or doing a right click in the gray area of the window as demonstrated in Figure 6.1. All surface types will show up including surfaces defined by points and macrobody surfaces. The surface number will be set by default when creating a surface. The editor uses the last valid surface number and increments it by one. The surface coefficients are typically entered by hand. For some of the simple surfaces you can use the mouse to set the coefficients to an approximate value by clicking on the screen. For example, for a simple sphere (SO surface), you can set the radius, by clicking on the screen. You can indicate that the surface is a reflective surface by clicking on the “Reflective” check box. You can assign a transformation to the surface, by either entering the transformation number in by hand or clicking on the “Transformation” button to bring up a list of available transformations for the input file. When you select a transformation, the number of the transformation is placed in the transformation text box. Select “Register” from the menu to create the surface and add it to the input file. Once a surface is created, the mode changes to “Create like” which will default to creating additional surface, just like the one that was created.

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6.2 Scanning a Surface You scan a surface, by clicking on the “Scan” mode and then dragging the mouse across the surface in the plot window. You can alternatively type the surface number in by hand. When you scan a surface, all the information about that surface is displayed in the surface window. 6.3 Deleting a Surface To delete a surface you first need to scan it in, by dragging across it with a mouse or by entering the surface number when in “scan” mode. Once the surface has been scanned in successfully, it can be deleted by selecting “Delete” from the menu. If the surface is used as part of a cell, the Visual Editor will not let you delete it. 6.4 Editing a Surface To edit a surface, you first need to scan the surface in and then change the mode to “Edit”. In edit mode you can change the surface parameters, including the surface type. Once you are done editing the surface, select “Register” to update the surface in the input file and update the plot windows. 6.5 Hiding and Showing Surfaces The surface “hide” and “show” menu options are used to hide and show surfaces. A surface that is shown will appear as an infinite surface and it will show up, even if it is not part of any cell. In order to make cells, the Visual Editor needs to show these infinite surfaces that are not part of any cell. The surface number for an infinite surface will have an “*” by it when displayed in the plot window. It should not be confused with a reflective surface which also has a “*”. Once a surface is used in a cell, it becomes a finite surface and the “*” is removed from the label and it looks like it would in a normal MCNP plot window. When you first enter the Visual Editor or when you do a “Save – Update” from the “input” window, all of the unused surfaces are hidden. You need to select the “Show->Unused” option to show the unused surfaces if you need them for creating cells. Because this is done fairly often when creating cells, it is included on the menu when you do a right click in the plot window. 6.6 Surface Comments The dollar comment ($) is in line with the surface description and is limited to 40 characters. The comment card is on its own line and can be 80 characters long. Both dollar comments and surface comments can be entered for each surface. 6.7 Entering Surface Dimensions in Inches The default is to represent all surface dimensions in centimeters. However, it is possible to enter surface dimensions in inches by selecting the “Inches” option. In this mode all dimensions are in inches, the plots will still be in cm and the surface dimensions will be converted to centimeters when creating the surface card for the input file.

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While in “Inches” mode, the dimensions of scanned surfaces will be in inches, the “Surface delta” will be calculated as inches, and the distance will also be calculated in inches. 6.8 Surface Distance In scan mode, click on the “Distance” check box to have the Visual Editor calculate the distance between two simple surfaces (planes, spheres, cylinders). Click the first check box and drag across the first surface and then click the second check box and drag across the second surface and the distance between the surfaces will be calculated. The Visual Editor will take the dimension of the first surface minus the dimension of the second surface, so it is possible for this value to be negative. This only works for surfaces of the same type. This value will be in inches if “Inches” is selected. It is possible to get a number of distances from a specific surface by getting the dimension for the first surface and then leaving the second check box checked and dragging across all surfaces for which you want the distance calculated relative to the first surface. 6.9 Surface Delta The “Surface Delta” button lets you create a new surface relative to an existing surface. Set the mode to “Scan” and drag across the existing surface. Next change the mode to “Create Like” and enter a value for the surface delta. Click on the Surface Delta button and this amount is added to the surface coefficient. This only works for simple surfaces such as planes, spheres and cylinders. For spheres and cylinders the delta is added to the radius coefficient. This value will be in inches if “inches” is selected. 6.10 Macrobody Surfaces All macrobody surfaces are supported and can be created, both in the surface window and in the surface wizard. If problems occur when creating or modifying macrobody surfaces, typically because of coincident surfaces, do a “Save-Update” in the input window to reset the Fortran memory and the plots.

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6.11 The Surface Wizard Figure 6.2 shows a view of the Surface Wizard. The surface wizard can be used to walk the user through the process of creating a surface. This can be particularly useful for creating macrobody surfaces. The Wizard also includes some options for creating some specialized quadratic surfaces including ellipsoids and a slanted cylinder as shown in Figure 6.3.

Figure 6.2. The surface wizard.

Figure 6.3. Special quadratic surfaces.

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7.0 The Cell Window Figure 7.1 shows the cell window. After the appropriate surfaces have been created, select “Cell” from the main menu to create a cell using these surfaces. In the cell window you can create, edit, or delete cells. The default mode is “Create New” for creating new cells. You also have options for creating cell lattices, and splitting a cell for biasing. In “color” mode, the cells will be colored according to their material. However, the default "B&W" mode is usually preferable since the plots are generated much more rapidly in black and white. In both Color and B&W mode, geometry errors are shown as dotted surfaces in red. These lines are easier to see in B&W mode.

Figure 7.1. The cell window.

7.1 Creating A Cell Below are the basic steps for defining a cell when the cell window is active: 1. The editor selects a new default problem cell number when you open the cell window

or after you register a cell, but you can change this if you prefer to use a different cell number.

2. Enter the material number for the cell from the keyboard, or bring up a list of defined

materials by clicking on the material button, then click on the desired material -- this enters both the material and its default density into the cell window. The material must be defined to appear in the material list window. To set the density, the material must be used someplace else in the input file, the editor will get density from other cells that use the material. If the material has not been used before, you will need to enter the density by hand. Note: you may want to simplify things by not using materials in the initial geometry model (just voids), but this does have the disadvantage that the material regions will not show up by color on the plots.

3. Enter the material density from the keyboard (positive if atom density and negative if

gram density) if not set by selecting the material using the material button. 4. Enter fill number and/or universe number for the cell if required for the cell. 5. Drag the mouse across each relevant surface on the plots to select the bounding

surfaces for a simple object. A simple object is one where the sense (+/-) of the

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surfaces bounding the object is the same everywhere inside the object. When doing a surface drag, verify that the editor found the surface by looking to see if the surface is displayed in the white area at the bottom of the cell window. If the drag was not successful, the error message "drag failed" will be displayed in this area, in which case you need to try to do the drag again. Occasionally, when there are inconsistencies in the geometry, a surface will not appear or there will not be a response when the mouse is dragged across the surface. Do a "show" on this surface and the drag should work. You may need to keep showing surfaces after each cell is registered until this inconsistency is removed.

6. Click the left mouse button inside the object to indicate the sense of the surfaces for

the object. Note that some of the surface numbers in the white area will change sign. 7. Choose the "Paste" button (with the left mouse button) to add this simple object to the

cell description, or the "Cut" button to cut out this simple object from the cell being formed. The white area now shows the surfaces with senses (and unions if needed) of the partial cell card.

8. Repeat steps 5-7 for each "paste" or "cut" operation until the cell is completely

defined. You can also enter "Not" "cell numbers" if appropriate. 9. "Register" the cell to create it, where the white area will give the message "CELL

REGISTERED". The plots will also be updated to show the new cell, where dashed lines will be replaced with solid lines along the portions of surfaces where valid cells are defined on each side of the surface.

If you do not want to use the mouse operations described above to create the cell, you can enter the cell description in by hand and then select “Register” to create the cell. 7.2 Discussion Of Cell Paste And Cut Operations The bounding surface description of the cell is defined through a series of "Paste" and "Cut" operations. The "Paste" operation allows a complex geometry to be created by pasting together simple convcave objects such as parallelepipeds, spheres, cylinders, or more general shapes. The "Cut" operation allows the user to remove a piece from inside of the currently defined cell. For example; to create a cell outside a cube but inside a sphere, the first step is to define the outer spherical portion of the cell by crossing the spherical surface with the mouse and then setting the sense with the mouse and doing a paste operation. Next remove the inner cube by crossing each of its six surfaces with the mouse, clicking inside the cube to set the sense of the surfaces and then using the "Cut" operation to remove the cube from the cell description. Finally select register to create the cell. The reason that only simple shapes can be used in creating a cell, is the sense of all the surfaces must be the same for all locations within all the surfaces. For example in Figure 7.2, to create cell 1 on the right, you will need to do two sequential paste operations. First add the upper rectangular region to the cell description by dragging across surfaces

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4, 6, 2, and 1, setting the sense by selecting a point in the center of these four surfaces, and then selecting paste. Second, add the other rectangular region by dragging across surfaces 4, 5, 3, and 2, selecting a point in the center of these surfaces, then selecting paste. Finally, select “register” to create the cell consisting of the union of these two rectangular regions

First point

Second point

Figure 7.2. Two sequential paste operations. This needs to done with two paste operations because the sense for surfaces 5 and 2 changes depending on the location inside cell 1. If you dragged across all six surfaces and then selected a point for the sense, the sense for surfaces 5 and 2 would change depending on where you clicked. Typically axial surfaces would also be involved in creating the cell with “Paste” or “Cut” operations, but they are not included here to simplify the discussion. The "Paste" operation creates a set of intersections, with the sense of the surfaces determined by the mouse location when the sense is entered. "Paste" allows the user to paste together a complex, even disjoint (although this is typically not desirable), cell from simple objects. The “Paste” operation adds the region (using the union “:” operator) to the cell being defined. The "Cut" operation creates a sequence of unions, using the opposite sense of the surfaces for the simple object. "Cut" allows the user to cut out simple objects one at a time. Typically the perimeter of the cell has been formed with "paste" operations before the "cut" operation, and the new cut will remove the defined region (using a cell intersection). There is a special case in the creation of the "outside world" cell, or for

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cells on the outer portion of a universe, where "cut" may be the only operation. Then the cut produces a number of unions describing the cell as the region beyond. Each time a cut or paste operation is made, the editor will take the portion already defined, encase it in parenthesis and add on the portion that is being cut or pasted. Because of this, complex cells created in the Visual Editor can sometimes be hard to understand when looking at the input file. 7.3 Special Sense Considerations To set the sense for the cell, it is important that the location for the sense is inside the region being defined in all three dimensions. Because the sense is set within a 2D plot window, the user must be sure that the sense is not on a surface and that it is inside the region that is being defined in the third dimension. For example, if the sense is being set in the XY plot window, the user must be sure the z elevation of the XY plot is inside the region being defined. 7.4 Creating a Cell with Universes The cell transformation number, universe number, and fill number should also be appropriately set. These options introduce complications in defining the geometry since the geometry creation is dynamic on the plots, so certain rules need to be followed consistently to enable the creation of such cells. As a general rule you need to use the following sequence in creating cells involving universes, fills, and transformations for a cell that is part of a universe that fills a cell: 1. Create the fill cell first at the origin, but do not include the transformation. If the

plots are too messy around the origin, you may need to use the "hide" option to hide some cells, and possibly surfaces, on the plots. In the cell window set the value for fill.

2. Create the universe cells contained inside the fill cell. Remember that you do not

include the outer bounding surfaces that are included on the fill cell created in step 1 above. In the cell window set the universe value equal to the fill value set in step 1 above for each cell, then register the cells.

3. If a transformation is involved, return to the cell created in step 1 and modify it by

using the cell scan-edit option. To scan the fill cell, you will need to enter the cell number by hand, since the fill cell will not show up in the plot windows. When the mode is set to edit set the transformation, by selecting the transformation button to select a transformation, or just enter the correct transformation number by hand in the cell window. The plots for this universe will shift to the appropriate transformed location. You must create all the transformations prior to using them in the cells.

If you have a universe inside of a universe, it is recommended that you create these from the inside out. This will require a little backtracking as you set transformations and universe numbers, but it should be the easiest method. Create the inside fill cell first,

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then the inside cells that have the universe value set to this fill value. At this point you can go back and transform the fill cell if needed. Next create the outside fill cell and all the cells that compose the universe inside this fill cell. You will need to edit the inside universe fill cell at this time and set the universe value to the fill value of the outside universe. Finally, you can now transform the outside universe if needed. 7.5 Using Undo A useful feature of the cell window is the “Undo” button. This button allows you to correct mistakes prior to a register. Both drags and clicks (to set the cell sense) can be "un-done" in reverse sequence one at a time. Even after a cell is registered the undo button can be used to undo drags and clicks by scanning the cell and editing it. This can only be done on cells created by the Visual Editor. 7.6 Register "Register" is the final step in the cell making process. Once the cell is registered it is officially incorporated into the geometry. All of the active plot windows with the “Refresh” button selected will be updated to show the newly created cell. After creating a number of cells, it is prudent to save the file using File->Save or backup the file by selecting the “Backup” menu option. 7.7 Scanning a Cell You scan a cell, by clicking on the “Scan” mode and then clicking inside a cell in the plot window. You can alternatively type the cell number in by hand. When you scan a cell, all the information about that cell is displayed in the cell window. 7.8 Deleting a Cell To delete a cell you first need to scan it in, by selecting the cell in the plot window with the mouse. Once the cell has been scanned in successfully, it can be deleted by selecting “delete” from the menu. If the cell is used in another cell as a not (#) cell, the Visual Editor will not let you delete it. 7.9 Editing a Cell To edit a cell, you first need to scan the cell in and then change the mode to “Edit”. In edit mode you can change the cell parameters. Once you are done editing the cell, select “Register” to modify the cell in the input file and update the plot windows. While in edit mode, if the cell was created with the Visual Editor, you can use the “Undo” option to undo the operations used to create the cell. This will not work on a complex cell created outside the Visual Editor. In edit mode you can select “Clear” to clear the cell description and start over defining the cell from scratch. The “Clear” button only clears the cell description, none of the other cell parameters are changed. You can also manually edit the cell by changing the cell description by hand and then selecting “Register” when you are done modifying the cell.

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7.10 Create like You can use the “Create like” mode to create a new cell similar to an existing cell. A common application of this is to create a new cell like a cell that already exists, but with a transformation. To use the “Create like” option, you need to first “Scan” in a cell and then change the mode to “Create like”. The Visual Editor will automatically update the cell number to the next valid number. At this point you can specify the cell parameters that you want to be different and then register the cell to create it. 7.11 Hiding and Showing Cells The cell “hide” and “show” main menu options are used to hide and show cells. This option is not used very much, but can be used to define an object at the origin (To be transformed later) over an existing geometry, by hiding the existing geometry. 7.12 Cell Comments The dollar comment ($) is in line with the cell description and is limited to 40 characters. The comment card is on its own line and can be 80 characters long. Both dollar comments and cell comments can be entered for a cell.

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7.13 Splitting a cell Another feature available in the cell window is "Register for cell splitting" near the bottom of the cell window. This allows you to divide a cell equally (by thickness, not by volume) into a specified number of smaller cells. This is useful for setting importances in a thick shield. To use cell splitting, create the cell that is to be divided, then instead of selecting “Register”, select "Register for cell splitting". Once this button is selected, another window comes up that allows you to specify the number of splits (number of cells created) and in some cases the type of splitting to be done. The editor will already know the type of cell being split so you should never need to change this. See Figure 7.3 for an example of splitting a cylinder created by cz surface 1 and pz surfaces 2 and 3.

Figure 7.3. Cell splitting options.

For a cell that will be split into n cells, possible geometry types for the splitting include:

1. “Sphere-in-Sphere” where n-1 radial surfaces are inserted between the inner and outer spheres, where the inner sphere can have a radius of zero.

2. “Sphere” where n-1 radial surfaces are inserted inside a sphere surface.

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3. “Cylinder-in-Cylinder” where the inner and outer cylinders can be divided either axially or radially -- in either case the inner cylinder radius can optionally be zero; or (2) the inner cylinder is completely inside the outer cylinder, and the region is divided into n cylinder-in-cylinder cells.

4. “Cylinder or Ring” where the inner and outer cylinders for the ring are the same

height and the ring can be split axially or radially, When the surface is just a cylinder, it also can be split axially or radially.

5. “Box-in-Box”, where n-1 surfaces are inserted between the inner and outer box in

each of the -x, +x, -y, +y, -z, and +z directions with uniform spacing between the inserted surfaces in each of the directions.

6. “Slab”, where a large parallelepiped region is divided with n-1 surfaces in the x,

y, or z direction as specified by the user. Once the split is registered the cell splitting window disappears, and the multiple cells that fill the original region appear in the geometry plots. The editor automatically creates the n new cells and all the surfaces that are needed.

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7.15 Creating a Square Lattice Note: Creating lattices as discussed in Sections 7.15 and 7.16 is relatively complicated and all types of configurations can occur. If you have trouble creating a lattice with the Visual Editor, you may first need to experiment with a simpler lattice or else enter the cells involving the lattice manually in the Input window with a “Save – Update” after the information has been entered to update Fortran memory and the plots. A square lattice can be created by selecting the square lattice option in the cell window. To create a square lattice, you need to specify the horizontal and vertical pitch along with the number of rows. You can also include axial regions, by specifying the number of axial regions. When requesting axial regions, you need to specify the upper and lower coordinates for the surfaces that define the axial regions. The Visual Editor will then create the surfaces required to create the lattice. Figure 7.4 shows the rectangular lattice window for a rectangular lattice with three axial regions.

Figure 7.4. The Rectangular Lattice window.

Once a lattice has been defined the universe fill array is displayed to allow you to define the universes filling the lattice. Universe values can be set in the lattice by selecting

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different parameters using the “Select” options and then setting the universe value using the “Set Universe Value” text box. For example, in Figure 7.4 column index 2 is selected and set to universe 3. Other options that can be used for selecting lattice locations include the universe number (allowing for a search and replace capability), the axial index, and j index (row). 7.16 Creating a Hexagonal Lattice A hexagonal lattice can be created by selecting the hexagonal lattice option in the cell window. To create a hexagonal lattice, you need to specify the pitch and the number of rows. You can also specify axial regions, by specifying the number of axial regions and then indicating the coordinates for the axial surfaces. The Visual Editor will then create the surfaces required to create the lattice. Figure 7.5 shows the hexagonal lattice window for a lattice with three axial regions.

Figure 7.5. The hexagonal lattice window.

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Once a lattice has been defined by the pitch, number of rows and number of axial regions, a fill array will be displayed. Individual universes can be set by selecting locations in the universe lattice using special selection options. For a hex lattice, available parameters are the axial index, universe number, row, flat and flat index. In Figure 7.5, rows 1 through 3 have been set to universe 3. 7.17 Special Hex Lattice Display Options The Visual Editor allows you to hide lower levels of a lattice by selecting the appropriate level number for the plot. For a complex geometry with a universe in a universe, it is possible to plot only the top universe by setting the plot level to 1. This can significantly reduce the plotting time for plots where the internal details do not need to be plotted. The Visual Editor also allows you to display the coordinates for the universe by setting the global check box to local. This will show the actual coordinates for which the surfaces were created prior to being moved by a transformation or by being include in a universe. There are a number of useful things that can be plotted for a hex lattice that can be found under the lat menu of the cell label button. You can plot the universe number for each lattice location, or various indices. 7.18 The Cell Wizard Figure 7.6-1 through 7.6-14 shows a series of plots of the cell wizard being used to create a cell. The cell Wizard will take the user through the process of creating a cell a step at a time. The Figures below show the steps that the Wizard will take to generate a cell composed of three paste operations. The first region is created in steps 1-4. The second region is created in steps 5-8. The third region is created in steps 9-12. The current active plot is shown in the wizard. This plot is for display purposes only, the dragging and over the surfaces and setting the sense with the mouse is done in the main plot windows.

Figure 7.6-1. Set the Mode to Create

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Figure 7.6-2. Select the Surfaces

Figure 7.6-3. Use the Mouse to Set the Surface Sense

Figure 7.6-4. Select Paste to Add the Region

Figure 7.6-5. Select the Option to Continue to Create the Second Region

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Figure 7.6-6. Drag across surfaces for the Second Region.

Figure 7.6-7. Set the Sense for the Second Region.

Figure 7.6-8. Paste the Second Region.

Figure 7.6-9. Select the Option to Continue to Create the Third Region.

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Figure 7.6-10. Drag across surfaces for the Second Region.

Figure 7.6-11. Set the Sense for the Third Region.

Figure 7.6-12. Paste the Third Region.

Figure 7.6-13. Select Finish to Create the Cell.

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Figure 7.6-14. Create the Cell.

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8.0 Materials Figure 8.1 shows a plot of the material window and the associated material library window and isotope selection window. The material library allows users to store commonly used materials in a file that can be accessed by the Visual Editor. It is possible to move materials from the input file to the library and from the library to the current input file. The isotope selection window is used to select the isotope cross sections (the zaid) that make up a particular material.

Material Window

Material Library Window

Isotope Selection Window

Figure 8.1. The material creation windows. 8.1 Creating a Material Prior to creating any materials, you must set the mode (N, P, E, etc.) for the problem by typing the mode card in the input window and selecting Save-Update. If you do not do this, the mode will default to neutron. The materials are created by choosing the "Data->Materials" menu option. This brings up a "Materials" window. At this point you can either read in materials from the material library or create new materials.

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For a new material, the material number will be automatically set. You can change this if the number you change it to is not already used. You then need to specify a material name and a material density (positive if atom density and negative if gram density). The material density will be the default used on cell cards for that material when selected in the cell window. The material composition is generated by specifying each isotope of the material and its mass fraction (negative) or atom fraction (positive). To do this, click on "Isotope:" in the "Material Descriptions" window. This brings up a table of the elements. Select an element with the left mouse button to bring up a menu showing the isotopes for that element. If this menu does not show up, then you “vised.defaults” file is not valid. Click on an isotope, to bring up the available cross section sets for the isotope. Choose the appropriate cross section set by clicking on it with the mouse. When you do this, that cross section set ID will appear under "isotope" in the material window. Enter the mass fraction or atom fraction for that isotope in the material being created in the adjacent "Fraction" box. Then select “Add” to add this isotope/fraction pair to the material description. At any time you can change these isotope/fraction pairs, by clicking on the pair to change. Notice the Edit check box is set, indicating that you are in edit mode. Change either the isotope or fraction. To get out of edit mode and create additional isotope/fraction pairs, you must unselect the “edit” check box. Repeat this for the other isotopes in the material. Then select "Register" to create the material and add it to the input file. 8.2 Scanning a Material There is no scan mode in the material window, instead whenever you click on one of the materials its composition is listed. 8.3 Delete a Material To delete a material, you need to select the material and then select the “Delete” option from the menu. This will delete the material, provided it is not used by any cell. 8.4 Edit a Material To Edit a material, click on the material, set the mode to “Edit” and then click on the isotope-fraction pair that you want to change. This will activate the “Edit” check box indicating that a isotope-fraction pair is being edited. At this point you can make changes to either the isotope or fraction or delete the isotope by pressing the “Delete” button. To get out of edit mode and enable the create mode to add additional isotope/fraction pairs, un-check the “Edit” check box. 8.5 The Vised.defaults File The Visual Editor needs to know where to find the material files for the material library to work. The Visual Editor also needs to know where xsdir is, to allow for the selection of cross sections from the isotope window.

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The Visual Editor will try to determine the location of the material files from the MCNP “DATAPATH ” environment variable. If this does not work, you need to specify the location of the material library with the vised.defaults file. To create a vised.defaults file, bring up the material window, by selecting “Data->Materials” and then select “Files” from the Materials window. This will bring up a window like that shown in Figure 8.2. Enter the full path for the location of each of the different files.

Figure 8.2. Select “Files” to set the location of the material library and xsdir files.

There are four types of material files that need to be specified in the File Locations window: stndrd.n: Standard material file containing neutron cross sections available for all users. stndrd.p: Standard material file containing photon cross sections available for all users. usr.n: User specific material file containing neutron cross sections for the individual user. usr.p: user specific material file containing photon cross sections for the individual user.

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Typically the stndrd.n and stndrd.p files are generated for a group of people to contain a set of commonly used materials. It is a good idea to keep these files in a central location, perhaps in the same directory where you store your MCNP executable. These files should be distributed with the Visual Editor executable. The usr.n and usr.p files are a set of materials defined by the individual users. You create the usr.n and usr.p files the first time you move materials (using the “Store” button) from your input file to the library. After entering the full path names for these files (see Figure 8.2), select the “Apply” menu option and a vised.defaults file will be created. The Visual Editor will read this file each time you start it up. This file must be in the same directory as the Visual Editor executable so the Visual Editor can find it. 8.6 Material Library You can transfer materials from the material library by selecting the “Library “ menu option to bring up the material library and then selecting the materials you want to include in your input file from the library of materials. If the materials do not show up then the “vised.defaults” file is not correctly defined. Select the materials you want to add from the library and select “Add” in the material library window to transfer the materials from the library to the input file. When the materials are first transferred to the input file, a default density is assigned to each material. When selecting the material in a cell using the “Material” button on the cell window, this default density is used for the cell density. However, if you go out of the Visual Editor and come back in, or do a “Save-Update” operation in the input window, these default densities are lost and the editor must then look to see if the material is used in the input file to get the density off the cell card. If the material is not used, the density will not be known and you will have to set it by hand. Caution: The standard materials compositions and densities have been selected from what is desired in a typical application. This requires a judgment in most cases. A composition and density that may be perfectly acceptable in most applications, may be very unacceptable in a special application. Trace element activation or temperature, for example, may mean important differences. When using standard materials, the user should always carefully review the acceptability of these materials. To add materials to the material library, select the materials that you want to place in the library and then select “Store” from the menu to transfer those materials to the user library. They will be placed in “usr.n” if they are neutron materials and they will be placed in “usr.p” if they are photon materials. Within the material library window, you need to select “Save” to update the user files.

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8.7 Material Options If you click on the “Options” check box, a number of text boxes will appear that allow you to fill in additional material options such as gas, estep, nlib, plib, elib. Refer to the MCNP manual for more information on these. These have not been tested very much. 9.0 Importances You can set importances by choosing “Data->Importances” from the main menu. From this Window, the importance for your problem can be set by selecting cells directly from the plot window and then setting their importance values. Figure 9.1 shows a plot of the importance window.

Figure 9.1. The importance window.

9.1 Setting Cell Importances The importance window allows you to set the importance of individual cells or groups of cells. You can select individual cells on the plot or drag across a series of cells. Once the cells have been selected, you can set them to a specific importance value by clicking on the “Set Importance” check box and then entering a value for the importance. Select “Register” to update the input file and the plots. 9.2 Using a Scale Factor You can multiply the selected importance by a scale factor, by selecting the “Factor” check box and selecting the “Scale Factor” option. Next, enter the multiplication factor into the “Factor” text box and all the importances will be multiplied by this factor. Select “Register” to update the input file and the plots.

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9.3 Using a Geometric Factor To set the importances using a geometric factor, select the “Factor” check box and then select the “Geometric Factor” option. To use the geometric factor you need to identify the starting importance and the factor to use in the appropriate text boxes. The Visual Editor remembers the sequence in which the cells were selected which can be used to assign a geometric factor to the importances. The Editor will use the starting importance as the importance for the first cell selected. For each additional cell selected, it multiplies the previous importance by the geometric factor. For example, if the starting importance is 4 and the geometric factor is 2, the first six selected cells would have importances of 4, 8, 16, 32, 64, 128. 9.4 The Importance Display If the display is set to “Decimal”, the importances are shown as decimal numbers as shown in Figure 9.1. If the display is set to “Power of 2”, the importances are shown as powers of 2, so 2, 4, 8, 16 becomes 1, 2, 3, 4. 9.5 Truncating importances When generating importances using a factor, especially a geometric factor that is not an integer, it is sometimes desirable to truncate the importances to an integer. If the Integer check box is selected, all the importances will be truncated to the nearest integer. Be careful when using this option, since all values below 1 will be set to zero.

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10.0 Transformations To create or modify transformations, select "Data->Transformations” from the main menu. The transformation window provides spaces to enter the elements of the transformation. When the correct coordinates have been entered, select "Register" to create the transformation and update the Fortran memory. This process may be repeated as many times as necessary for subsequent transformations. Figure 10.1 shows a view of the transformation window.

Figure 10.1. The transformation window.

The “Origin” button indicates if the rotation is relative the main axis or the axis being transformed to. The “Units” button indicates the units for the values in the rotation matrix, the default is “Degrees”, but this can be changed to “Cosine Theta” in this box. For more information on the “Origin” and “Rotation Units” options, refer to the MCNP manual.

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11.0 Renumber Cells/Surfaces The surface and cell numbers in the input file can be renumbered by bringing up the renumber panel shown in Figure 11.1. The user indicates the starting cell number and starting surface number to use when the cells and surfaces are renumbered and the Visual Editor will renumber the cells and surfaces in the input file.

Figure 11.1. The “Surface/Cell renumber” window.

This feature can be used to combine two input files into a larger combined input file, by renumbering the surfaces and cells of one of the input file in a range that will be beyond the maximum surface and cell number in the other input file. For example, if each of the input files contains 100 cells and 100 surfaces, the user could renumber the first input file starting with cell number 1 and surface number 1 and perhaps renumber the second input file starting at cell number 500 and surface number 500. The files could then be combined without the surface numbers conflicting between the two files. Additional work will need to be done by the user to make sure the cells, such as the outside world, do not doubly define space.

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12.0 Run The “Run” window can be displayed by selecting “Run” from the main menu. The “Run” window will allow you to run input files without going outside the Visual Editor. Figure 12.1 shows a view of the “Run” window. To run an input file, it must be in the same directory as the Visual Editor executable.

Figure 12.1. The “Run” window.

To run an input file, enter the name of the input file and optionally the output file and other files involved in the run, then select “Run” from the menu to run the problem. This will run the MCNP that is compiled as part of the Visual Editor, it does not run the MCNP that you may have installed outside of the Visual Editor. A valid copy of the xsdir file is required to run files in the Visual Editor just like it is needed for running a normal MCNP input file. As the problem is running the number of particles run and the amount of time used in the run so far is constantly updated at the top of the window. While running the problem, you can select the “Stop” button to gracefully stop the run. Notice that you can also enter options (i, x, r, p) that will be used for the run. Some options will not work such as the “z” option for plotting tallies. Instead you need to select the “Tally Plots” option from the main menu to do tally plots.

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If you select the option to overwrite existing files, the files that you specified will be removed before the run starts to prevent the file names from incrementing. The Visual Editor can also run input files from the command prompt, by typing a command line similar to that for MCNP such as “vised inp=ipig outp=opig”. This also allows the Visual Editor to be included in batch files. When the Visual Editor runs MCNP from the command prompt, it brings up the Visual Editor, along with the “Run” window and runs the input file inside the “Run” window. When the run is over, the “Run” window and the Visual Editor are closed. 13.0 Particle Display To display source points or particle tracks, select “Particle Display” from the main Window menu. Reference 6 has a good summary of the particle track plotting capabilities of the MCNP Visual Editor. Figure 13.1 shows the particle display window. This window provides three primary options: source point plotting of the SDEF source; KCODE source generation point plotting; and particle track plotting, which can also be used to display the SDEF source. The points are projected onto the 2D plot plane defined by the currently active plot for all three options. The distance from the plot plane defaults to 100. The user can change this value. If a particle event occurs outside this range it is not plotted.

Figure 13.1. The particle display window.

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13.1 SDEF Source Plotting For problems with an SDEF source, you can select to do a display of the source starting points by selecting the “SDEF” option. This will plot the starting source point locations. You can set the number of points to plot in the “Number of Particles” text box and you can set how far away from the plot plane points will be plotted in the “Distance from the Plot Plane (cm)” text box, the default is 100 cm. Since the plot represents a 2-D plane through the geometry, all points at the defined distance away form the plot plane will be projected onto the plot. Because of this, it is possible to see source points on the plot plane for source geometries that do not show up in the plot. After doing a source plot, the number of particles successfully plotted will be displayed. This can be used to provide useful information about the source or the source biasing. 13.2 KCODE Source Plotting For a KCODE problem, the Visual Editor can be used to plot the source generation points for each cycle, where cycle “1” is defined to be the source points for the initial KSRC defined in the input. The cycle numbers are specified in the “cycles” text box. The cycle numbers must be monotonically increasing separated by blanks or commas or a dash to represent a range of cycles. For example 1-5 to indicate cycles 1 through 5. The source points per cycle are written out as a set of source files with names srcz”n”, where the “n” represents the cycle number. After the cycles have been specified, select the “RUN” option, then select “Plot” at the top of the window to run MCNP with the previously opened input file. When “Plot” is selected, the Visual Editor will execute MCNP and write out the cycles requested by the user. The input file will run to completion, but will only write out the requested cycles. If the user specified cycles 1-5, but the input file runs for 10 cycles. The code will still run for 10 cycles when “Plot” is selected, even though only the first 5 cycles are written to srcz”n” files. After doing a “RUN”, you can plot the source generation points by selecting the “PLOT” KCODE option, which will read the srcz”n” files and display the points on the plot. It is up to the user to verify that the source points from the srcz”n” files correspond to the geometry being plotted. The KCODE particle plot can be made in two different modes, either “Cumulative” or “Animate.” If the “Cumulative” option is selected, all of the source points generated for all of the selected cycles are plotted, giving a cumulative source point density plot. If the “Animate” options is selected, the source generation points for each cycle are plotted then erased to plot the next set of points, producing an animation of the source generation points for the specified cycles.

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13.3 Particle Track Plotting For both SDEF and KCODE Problems, the Visual Editor can be used to plot particle tracks by selecting the “TRACKS” Option. The user must set the “Number of Particles” and the “Distance from the Plot Plane (cm)”. Next the events to be plotted must be selected with the option button to the right of “TRACKS”. Possible events include source points, surface crossings, tally contributions, and collision points. The default is to plot collision points. Finally, select “Plot” from the menu to run MCNP and generate the points. This does not run the MCNP on your system, but instead the MCNP that comes as part of the Visual Editor package. For the “TRACKS” option, you can choose to only plot those collision that lead to an eventual contribution to a tally. This can be helpful in determining how particles get to a particular tally. To activate this option, select the “Tally Contributions Only” check box. There is an additional option to indicate the tally number for which contributions will be plotted, and another option for the Segment Number if an fs card is involved for the tally (“1” for the first entry on the fs card, etc.). It is recommended that all tallies except the tally of interest be removed from the input file. The Visual Editor does not “connect the dots” when doing particle track plotting, instead, it only plots the points of interest, such as collisions, where each point will represent a collision. 13.4 Setting Point Color and Size In particle track plotting, the colors will vary from Red to Blue depending on the energy of the particle, depending on the energy or weight of the particle prior to collision. Every time a particle is plotted, the code will adjust the maximum and minimum values plotted so far and will change the color depending on the weight or energy of the particle. This is not very precise, since the max and min range will change as more particles are run. There are a number of different options that will set the particle color and size. The “Color By” option allows you to specify what the color of the point represents. For particle tracks the color varies from blue to red, when “color by” is set to energy, blue corresponds to a low energy event and red to a high-energy event. When “color by” is set to weight, low weight events will be blue and high weight events will be red. You can set the size of the point plotted by changing the “Point” size. The default is to use the “Pixel” size, which is the smallest size, but does not show up on the printer very well. There are five other increasing larger point sizes that can be selected for displaying the points. Additionally, the “Border” check box can be selected to create a dark border around each of the points. 13.5 Setting Energy or Weight Ranges You can specify the energy range or weight range that should be plotted by selecting either the “Energy range” check box or the “Weight range” check box and then entering the minimum and maximum values that will be plotted.

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13.6 Problems Generating Particle Tracks Getting source plotting and particle track plotting to work correctly can take some effort. Below is some advice on how to overcome common problems.

1. For SDEF plotting, you are executing the source point generation routine. For plotting KCODE cycle generation points and particle tracks, the input file is run by the MCNP portion of the Visual Editor. Because of this it is a good idea to make sure the input file does not have any fatal errors in the source, so run it in MCNP first.

2. If it runs in MCNP and still crashes while plotting in the Visual Editor, look at the

output file (outp) and the “outmc” file to see if you can find any fatal errors. 3. KCODE cycle plotting and particle track plotting will fail if you are using a

binary cross section set that is not consistent with the compiler that was used to compile the Visual Editor. In this case you will need to switch to an ascii cross section set or regenerate the binary cross sections in a compatible manner.

4. Make sure a valid xsdir is in the same directory as the input file being read by the

Visual Editor. Since you are now running the code, the vised.defaults file will not be used to find the xsdir file. The xsdir in the directory where the Visual Editor executable is stored is not used for particle track plotting.

5. When doing KCODE cycle running using the “Run” option, you should not run

the problem beyond the last cycle specified in cycles, since you will not be generating any new information.

6. Particle track plotting for tally contributions seems to work best if you only have

the tallies of interest in the problem you are running.

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14.0 Tally Plots The Visual Editor will allow the plotting of MCNP tallies. In general it makes available the plotting capabilities currently available in the MCPLOT plotting package discussed in Appendix B of the MCNP manual. Figure 14.1 shows the tally plot window along with the two additional windows used to set the titles and tally plotting parameters. To display tally plots, you first need to read in a valid runtpe or mctal file. In the top of the tally window, indicate the type of file and it’s name. Next select “Start” from the menu. This will cause MCNP to read in the file so it will be ready to do tally plots. At this point you can select “Plot” from the menu to generate the default tally plot. Set plot titles and plot axis titles in the panel obtained from selecting "Titles" at the top of the "Tally Plotting" window. Choose plot options, such as loglog, in the panel obtained from selecting "Options" at the top of the "Tally Plotting" window. These two panels should be left open until you want to divert back to the original defaults for generating the tally plot.

Figure 14.1. The tally plotting window.

Tally plots are easier to see when the plot window has been set to rectangular so you may want to click on the “Rect” check box to the left of the plot window.

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Most of the capabilities of MCPLOT as outlined in Appendix B of the MCNP manual are available using the Visual Editor interface. The titles can be changed by selecting “Titles” from the menu and other plot options, also discussed in Appendix B, can be set by selecting “Options” from the plot menu. When you change the plot parameters you will usually need to select “Plot” from the menu to update the plot. 15.0 Cross Section Plots The Visual Editor will allow the plotting of MCNP cross sections. In general it makes available the plotting capabilities currently available in the MCPLOT plotting package discussed in Appendix B of the MCNP manual. Figure 15.1 shows the tally plot window along with the two additional windows used to set the titles and plotting parameters. To display cross section plots, you first need to read in a valid input file. Enter the name of the file at the top of the cross section plotting window. Next select “Read” from the menu. This will cause MCNP to read in the file so it will be ready to do cross section plots. At this point you can select “Plot” from the menu to generate the default cross section plot.

Figure 15.1. The cross section plotting window.

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Cross section plots are easier to see when the plot window has been set to rectangular so you may want to click on the “Rect” check box to the left of the plot window. Most of the capabilities of MCPLOT for cross section plotting as outlined in Appendix B of the MCNP manual are available using the Visual Editor interface. The titles can be changed by selecting “Titles” from the menu and other plot options can be set by selecting “Options” from the plot menu. When you change the plot parameters you will usually need to select “Plot” from the menu to update the plot. Only cross sections for materials and isotopes specified in the input file can be plotted. 16.0 3D Ray Traced Image To generate 3D ray traced image of the plot of the geometry, select “3D View->Ray Traced Image” from the main menu. There are two general types of plots that can be made. The first is a color ray trace image and the second is a radiographic image. The radiographic image will generate a black and white plot that shows the density of the objects in the plot. This density can represent track length or can represent the track length times the cross section for a specific source energy. Figure 16.1 shows the Visual Editor displaying both types of plots.

Figure 16.1. Two different types of 3D rendering.

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16.1 3D Color Plots To create a 3D color plot, you first must have a completely defined input file that will execute without fatal errors. This option will not work on partial files. Read the input file into the Visual Editor. Then set a 2D plot window so that it will become the image plane of the 3D plot with the appropriate (x,y,z) origin and the desired extents; i.e., rays will be traced from the “viewpoint source” to the rectangle defined by this image plane (and beyond), where the basis vectors of the 2D image will automatically be adjusted to represent an image plane that is perpendicular to the source-point-to-origin-of-the-image-plane vector. Inside the 3D plotting window, set the viewpoint for the 3D geometry, this viewpoint must not be on the plot plane and cannot be in a zero importance cell. You need to specify which cells are to be displayed in 3D. The cells can be listed with either spaces or commas separating the different cells. A range of cells can be indicated with a dash. For example 1-5 would display cells 1 through 5 in 3D. If you specify a cell that does not exist in the input file, a warning message will be printed. You need to be careful to not include the outside world as one of the cells to display in 3D, or the cell that contains the 3D source for the plot. A number of options can be set to change the look of the plot. Once these have been set, select “Normal 3D plot” from the menu to generate a 3D plot. 16.2 3D Update the Plot Basis To generate a 3D plot, MCNP needs to make sure the view is orthogonal to the plot plane and will adjust the basis to make this happen. The basis vectors used for the plot are shown. If you check on the “Update Plot Basis” check box, the plot basis vectors will be updated to reflect these new values. 16.3 Color by Cell/Surface If the “Color by cell” option is set, the color represents the material in the cell. This is the default option. If “Color by surface” is selected then each surface will be shown in a different color. 16.4 Draw Lines Around Cells If “Draw lines around cells” is selected, a black line is drawn around each cell. This is the default option. If “No lines around cells” is selected, only the color shading of the cells is shown. 16.5 Color Cells by Material If “Color cells by material” is selected, each cell is colored according to its material type. This is the default option. If “Do not color cells” is selected, the cells are not colored. If you also select to not draw lines, then nothing is plotted.

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16.6 3D Shading If “Use 3D Shading” is selected, the color of each cell is darkened as the angle between the view and the reflection off the object increases, providing a 3D look. This is the default option. If “Use 2D shading”, is selected, the color of the cell is kept constant independent of the angle between the view and the reflection off the object. 16.7 Distance Shading If “Use distance shading” is selected, cells that are further away become darker. This is the default option. If “No distance shading”, is selected, the cells stay the same color independent of the distance away from the view. 16.8 Point/Plane Source Type If “Point source” is selected, the source points for the rays are all generated from the view specified by the user. This is the default option. If “Plane source” is selected, the source points are generated on a plane that intersects the view and is parallel to the plot plane. This will generate a plot as seen from an infinite viewpoint. 16.9 Show the Plot Plane If “Hide the plot plane image” is selected, particles do not stop at the plot plane, but continue until they enter the outside world. This is the default option. If “Show plot plane image” is selected, the plot plane image will be shown if a 3D cell has not been found by the time the ray hits the plot plane. This allows for the combination of both 2D and 3D plotting. For this option to work, you also need to set the “Stop at the plot plane” option. 16.10 Hide/Show Cookie Cutters If “Hide cookie cutters” is selected, the cookie cutter cell is ignored and will not be used to create a cut away view of the geometry. This is the default option. To create a cut away view of a 3D image, create a cookie cutter cell as described in the MCNP manual. Then select “Show cookie cutters” to cut out everything inside the cookie cutter cell. 16.11 Plot to the Outside World/Plot Plane If “Plot to the outside world” is selected, this will create all 3D images of all the cells found until the ray hits the outside world. This is the default option. If “Stop at the plot plane” is selected, the ray tracing will stop at the plot plane and will optionally show the plot plane image if “Show plot plane image” is enabled. 16.12 Plot Resolution The “Res” text box sets the resolution that will be used to generate the 3D ray-traced image. The default is 300. The higher this number the better the 3D image will look, however, higher resolutions take a long time to generate.

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16.13 3D Radiographic Plots To create a radiographic plot, set up the geometry plot as if doing a normal 3D plot. Additionally, you must set the maximum ray length which will correspond to pure black. If this value is not known, create a plot using a temporary non-zero value then look at the output display at the bottom of the window. The maximum radiographic length as calculated by MCNP will be displayed. You can then use this value to create an accurate radiographic plot. The user can also select to multiply the track length by the cross section for a given source energy. If this option is selected, both the maximum ray length and the energy of the source particle must be specified. Most of the plot options and features are ignored when doing the radiographic view. The only plot option that can be changed is to plot from a point source or a plane source, all other options are ignored. To generate the radiographic plot after all of the parameters have been set select “Radiographic 3D” from the menu. 16.14 3D Transparent Plots Set up a transparency plot like a normal plot, except there are two additional parameters that need to be specified, the “cell transparency” and the “Average Cell Thickness”. The user will not typically know what these values are without first generating a transparent plot using the default values. After the plot is generated, the code will print out the average “cell thickness” and the “maximum non-transparency”. Generate the plot again using the calculated cell thickness and scaling the transparency value so that the calculated non-transparency will be less than 1. The non-transparency value indicates the maximum saturation of color that was generated. If this value is greater than 1.0, then the color goes to pure white where this happens in the plot and the user should lower the “cell transparency” until the reported “maximum non-transparency” is less than 1.0. 17.0 Dynamic 3D Display The Visual Editor has a dynamic 3D display option that will generate a 3D geometry that can be rotated with the mouse and the transparency of the cells can be set. Figure 17.1 shows a geometry of a cask generated using this feature.

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Figure 17.1. Dynamic 3D Display.

The dynamic 3D display does not work for lattices and universes and can be slow in generating complex geometries. There are a number of options for moving around the geometry including “Roll”, “Pitch” and “Yaw” options that allow the viewpoint to moved dynamically around the model. There are also a number of visibility options for the cells including wireframe and transparent. Figure 17.2 shows a transparent view of the geometry.

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Figure 17.2. Dynamic 3D Display with a Transparent Geometry.

The resolution used to generate the geometry can be changed, but a higher resolution will typically take longer to generate. By default, all cells that contain a material will be displayed. To display individual cells, un-select the “Display Cells with Materials” check box and then enter the cells to display in the “Cells to Display” text box. 18.0 CAD Import The Visual Editor can read and convert some 2D dxf and 3D sat CAD files to an MCNP input file. 18.1 2D CAD Import An algorithm was created to read in a CAD dxf file using a dialog added to the MCNP Visual Editor. To access the panel for importing a 2D CAD file, the user needs to select CAD import ->2D Import from the main menu. This will bring up the “CAD Import” panel. The user can then select “Import” to read in a CAD dxf file. The CAD geometry can then be displayed prior to converting it to an MCNP format by selecting the “Update” button for one of the plots. For every line that crosses another line, the Visual Editor will segment the lines. This is necessary to prevent multiply defined spaces in the MCNP geometry. It also allows the user to remove a line segment using the “scan” and “delete” options on the “CAD

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import” panel. To segment the lines, the user selects “Segment” from the “CAD Import” panel. Figure 18.1 shows a plot of the surfaces before and after segmenting. Notice that both the lines and circles are segmented. The geometry has still not been converted to an MCNP format. At this point the user could choose to delete a segment by scanning the segment in and then choosing the “delete” option.

Figure 18.1. CAD geometry before and after segmentation

To convert the file, the user selects the “Convert” option to create the MCNP surfaces and MCNP cells. It is not necessary to segment the CAD file before converting, if the user has not yet selected the segment option, the code will automatically detect this and do the segmenting prior to converting the file. Once the file has been converted to MCNP, the user should then select “Input” from the main Visual Editor menu and do a “Save-Update” in the resulting “Input File” panel to display the MCNP plots. This conversion works for most of the CAD geometric entities including, lines, polylines, multilines, circles, arcs and ellipses and also works for the insertion of blocks. These geometric entities include most of the 2D geometries that can be created by CAD. The Visual Editor will display these geometric entities and allow the user to select any of these items and remove them from the geometry (by scanning them and selecting the “Delete” button) before converting them to MCNP. This can be done either before or

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after segmenting the surfaces. The Visual Editor will also allow the insertion of an upper and lower surface to bound the 2D geometry in the axial direction. Figure 18.2 shows an example 2D CAD file that has been converted to MCNP. The original CAD file is shown in the left plot window and displayed using the new Visual Editor CAD plotting capabilities. The converted MCNP file is shown in the right plot window. The original CAD file contains lines, polylines, polygons, multilines and circles. The resulting MCNP geometry has 88 surfaces and 31 cells. The first few lines of the resulting MCNP input file can be seen in the input window at the bottom of the figure.

Figure 18.2. CAD geometry before and after conversion.

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18.2 3D CAD Import The 3D conversion capability allows for importing 3D CAD geometries that were created in CAD using “perimeter modeling” or “solid modeling”. The type of import should be set in the 3D CAD import window, prior to importing the geometry.

“Perimeter modeling” is designed for a geometry that is created with CAD by defining only the perimeter of each body. The conversion then determines each MCNP cell as the outer perimeter along with the algorithm to determine any inner perimeters for that cell. Perimeter modeling requires that the CAD bodies be completely contained inside each other, although they can share one or more common face. With perimeter modeling unions and intersections are not allowed. An example of perimeter modeling is shown in Appendix B.

“Solid modeling” allows for a CAD model where all space is defined, including void spaces, but doubly defined space is not allowed. This is the type of model that is typically used for manufacturing. With solid modeling a minimum number of subtractions and unions are allowed.

For conversion to MCNP, perimeter modeling is preferred because the CAD geometry is simpler and much more reliable for conversion. This document will focus on perimeter modeling unless otherwise stated. The 3D CAD file must be exported from CAD in a SAT format in order to be read into the Visual Editor. The SAT format was used because it is a universal format that can be written and read by most CAD packages. The SAT format supports five different types of surfaces. MCNP has equivalents for the plane, cone (which includes cylinders), sphere, and torus. The program can successfully convert all these surfaces. SAT also supports a spline surface that is modeled by a third order polynomial (or greater). Because MCNP does not model above a second order polynomial, SAT splines had no direct MCNP equivalent. Figure 18.3 shows examples of some of CAD objects that can be converted.

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Figure 18.3. Assorted CAD Objects Drawn in a CAD Package

Figure 18.4 shows a 3D display of the CAD objects (shown on the right), after they have been imported into the Visual Editor. These were then converted to MCNP. The 2D MCNP plot of the geometry is shown in the left of the figure. The top of the input file is shown on the bottom left.

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Figure 18.4 CAD Objects in the Visual Editor after Conversion

A number of features were included in the Visual Editor CAD conversion program to aid in the conversion of 3D CAD files, including the ability to parse a complex object made of a number of unions into simpler objects that are easy to convert and the ability to convert objects with a small number of unions or intersections.

Many files created without prior intent for use with MCNP contain complexities that are not important for MCNP and as such need to be modified to meet the conversion constraints. 18.3 Constraints/Restrictions for 3D CAD Conversion Because CAD programs place no real world restrictions on the geometry created, it was necessary to define what constraints must be applied on the CAD software so that the resulting SAT file could be converted to a valid MCNP geometry.

1) Each CAD surface must be expressed as a general (second order) quadratic in x, y, and z. Splines cannot currently be converted.

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2) The CAD model must define all of space. This means that regions of air need to be defined as objects so they can be converted to the proper MCNP cell.

3) The CAD geometry should be inside a large box, or cylinder, or sphere, where the

region beyond this large box, or cylinder, or sphere in the conversion will be defined as a MCNP cell for the “outside world” cell; i.e., with an importance of zero.

4) A CAD region is limited in its complexity, so that the resulting MCNP cell does

not exceed the limits of an MCNP cell. If the cell is too complex, it must be split into simpler cells.

5) For CAD solid modeling, a limited number of unions and intersections are

allowed; however, if an object is too complex, it must be split into a number of simpler cells.

Although these constraints add some additional burden to the CAD designer, it will result in a more efficient MCNP model that is not overly complex.

18.4 Using CAD as a Graphical User Interface for MCNP with Perimeter Modeling If a CAD file does not currently exist, the conversion program allows for the import of a simplified CAD geometry that can be converted to an MCNP format. The special format defines solids that are entirely contained inside each other or sharing a common face. This algorithm is designed for a geometry that is created with CAD by defining only the perimeter of each body. The conversion then determines each MCNP cell as the outer perimeter along with the algorithm to determine any inner perimeters for that cell.

18.5 3D Display of Imported CAD Files Once the geometry has been imported, a 3D visualization of the CAD geometry is displayed. The user can use the mouse to move around the geometry and change the visibility of individual cells (hidden, solid, transparent or wireframe). Each cell is displayed in a different color to help differentiate between the different imported bodies.

Figure 18.5shows an example of the display of imported bodies as read from the SAT file. The top of the building is made transparent, and the pillars and central cone have the wire frame removed so they appear solid. Details concerning the SAT file are shown in the right side of Figure 18.5, where each body displayed is identified. When the user clicks the mouse on a body in the plot window, the selected object will be identified in the bottom panel on the right. The user can rotate the 3D image and move around the object as desired, using the “rotate” button or the “yaw”, “pitch” and “roll” buttons.

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Figure 18.5. 3D CAD Visualization

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18.6 Conversion of Large Files To show that the CAD conversion works for large files, a 1,000-sphere case was created. Each set of 25 spheres was enclosed in a rectangular parallelepiped, to minimize the number of surfaces used in the creation of the cells in the resulting MCNP geometry. Without the parallelepipeds, the resulting air space between the 1,000 spheres would be too complex for MCNP. Figure 18.6 shows the 3D display of the spheres with the boxes hidden on the front, so the spheres can be seen, and some of the boxes set to transparent in the back. The resolution of the spheres has been reduced to enable faster geometry manipulation. The resolution used to generate a curved surface is set with the resolution text box and indicates the number of intervals to use in 360 degrees.

Figure 18.6 3D Display of 1,000-Sphere Geometry

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Figure 18.7 shows the resulting MCNP geometry and input file after the CAD file has been converted to MCNP.

Figure 18.7 MCNP Geometry with 1,000 Spheres

19.0 Read again Some users may decide that they want to use their own text editor instead of the one provided in the Visual Editor. You can do this to some extent by opening the input file in your favorite text editor, then opening the same file in the Visual Editor. The Visual Editor has been configured to allow it to read a file in use by another program. After making changes by hand to the input file in the text editor and saving the updated file in the text editor, select “Read_again” in the input window and it will read the input file again and update the plot windows to reflect changes that have been made. Alternatively, the file can be opened with the File->Open (do not modify input) option which will read in the input file without modifying it. This will disable the creation capability of the Visual editor (surfaces, cells, materials, etc.) but the visualization features will still be available (2D plots, 3D plots, particle tracks, etc.). In this mode, the unmodified input file will be displayed in the input window. Modifications to the input

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file can be made in this window and the plot will be updated when save-update is selected. 20.0 Backup Inp "Backup Inp" takes what is in memory and writes it out to the file inpn1, inp2, inp3, … which sequentially increases like other MCNP output files. This will allow the user to recover if an error occurs that causes the Visual Editor to crash. It will also allow the user to keep track of previous versions of the same file making it possible to go back to an earlier version if something goes wrong. 21.0 Problem Reporting The Visual Editor is constantly being upgraded to fix problems in the code. Some problems are known and have not yet been fixed, because they do not occur very often. A list of bugs will be maintained on the Visual Editor web site at www.mcnpvised.com. Before reporting a bug, make sure you check the outp and outmc files to see if it can provide some additional information about the problem. 22.0 References 1. R. A. Schwarz, L. L. Carter, and N. Shrivastava, "Creation of MCNP Input Files With

a Visual Editor," Proceedings of the 8th International Conference on Radiation Shielding, Arlington, Texas, April 24-27, 1994, pp 454-459, American Nuclear Society, La Grange Park, Illinois(1994).

2. L.L. Carter, R.A. Schwarz, “Visual Creation of Lattice Geometries for MCNP

Criticality Calculations,” Transactions of the American Nuclear Society, 77, 223 American Nuclear Society, La Grange Park, Illinois (1997).

3. R.A. Schwarz, L.L. Carter, “Visual Editor to Create and Display MCNP Input Files,”

Trans. Amer. Nucl. Soc., 77, 311-312 American Nuclear Society, La Grange Park, Illinois (1997).

4. R.A. Schwarz, L.L. Carter, K.E. Hillesland, V.E. Roetman, “Advanced MCNP Input

File Creation Using the Visual Editor,” Proc. Am. Nucl. Soc. Topical, Technologies for the New Century, 2, 317-324, April, 1998, Nashville TN.

5. L.L. Carter, R.A. Schwarz, “The Visual Creation and Display of MCNP Geometries

and Lattices for Criticality Problems,” Trans. Amer. Nucl. Soc., American Nuclear Society, La Grange Park, Illinois (1999).

6. R.A. Schwarz, L.L. Carter, W Brown, “Particle Track Visualization Using the MCNP

Visual Editor,” Proc. Am. Nucl. Soc. Topical Radiation Protection for Our National Priorities Medicine, the Environment and, the Legacy, 324-331, 2000, Spokane, Washington.

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7. R.A. Schwarz, L.L. Carter, “Current Status Of the MCNP Visual Editor,” 12th Biennial RPSD Topical Meeting, April 14-18, 2002, Santa Fe, New Mexico.

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Appendix A In this sample problem, we will create a small sphere inside a cross that will be placed inside a larger sphere. Simply follow the steps shown on the next page for this creation. Timesaving note: Even though this example is reasonably straightforward, there is a high probability for a new user to make an error and lose some or all the data that was created. It is a good practice to periodically save the current input file by repeating steps 85 to 87 with a different file name each time. Alternatively, you can select “Backup” from the main menu and it will save the file to “inpn?”, where the “?” is a number (inpn1, inpn2, inpn3, etc.). If an error occurs you can exit the Visual Editor and then start it up again and read in your last saved file and pick up at that step in the creation. The cell menu also has an “undo” option that will cancel the last operation performed when creating a cell (drags, points, paste, cut) so if an error occurs when creating a cell you can remove the last action using the undo button.

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Start the Visual Editor

STEP ACTION DESCRIPTION

1. Start the Visual Editor Use Windows Explorer to start the Visual Editor.

2. Select input Open the “Input” window.

3. Enter a title before the line containing a default comment card

Enter the title “Simple problem” at the top of the input window, then PRESS RETURN.

4. Select “Save-Update” Update the Fortran memory.

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Create the small sphere 5. Select “Surface” from the

main menu. Get ready to create surfaces.

6. In the surface window set R to 20.

Set the radius of the default “so” surface to 20.

7. In the surface window, select “Register”.

Create the surface, which will now appear in the plots.

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Set the Surface Labels. 8. Set the Surface label size

to 30 in the left window. Make the labels larger so they can be seen.

9. Click on “Surf” in the left plot window.

Show surface labels.

10. Set the Surface label size to 30 in the right window.

Make the labels larger so they can be seen.

11. Click on “Surf” in the right plot window.

Show surface labels.

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Create a cell consisting of the small sphere. 12. Select “Cell” from the

main menu Get ready to create cell 1 inside the small sphere.

13. Drag across the sphere in the left plot window.

Select the sphere surface. The “1” appears on white area of cell panel.

14. Click the mouse inside the sphere.

Set the sense for the surface of the sphere. “POINT ACCEPTED –Select Past or Cut” appears on white area of cell panel.

15. Select “Paste” Add the sphere to the cell description.

16. Select “Register” Create the sphere cell.

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Set the Cell Labels. 17. Set the Cell label size to 40

in the left window. Make the labels larger so they can be seen.

18. Click on “Cell” in the left plot window.

Show cell labels.

19. Set the Cell label size to 40 in the right window.

Make the labels larger so they can be seen.

20. Click on “Cell” in the right plot window.

Show cell labels.

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Set the Surface Type to PZ 21. In the “Cell” window, select “Close” Close the cell window to reveal the surface window.

22. In the “Surface” window, select “Activate” Make the surface window the active window. You can also just click on the top of the surface window to activate it.

23. In the surface window select “Surfaces->Plane->pz”

Set the surface type to “pz”.

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Create the PZ surfaces for the cross. 24. Set D to –80 Set the pz coefficient to –80 for the bottom of the cross.

25. In the surface window, select “Register”. Create the surface, only the left plot is updated.

26. Set D to -25 Set the pz coefficient to –25, notice the type is still “pz”.

27. In the surface window, select “Register”. Create the surface, only the left plot is updated.

28. Set D to 25 Set the pz coefficient to 25.

29. In the surface window, select “Register”. Create the surface, only the left plot is updated.

30. Set D to 80 Set the pz coefficient to 80.

31. In the surface window, select “Register”. Create the surface, only the left plot is updated.

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Create the PX surfaces for the cross. 32. In the surface window select “Surfaces-

>plane->px” Set the surface type to “px”.

33. Set D to -80 Set the px coefficient to –80 for the left side of the cross.

34. In the surface window, select “Register”.

Create the surface, only the left plot is updated.

35. Set D to -25 Set the px coefficient to –25, notice the type is still “px”.

36. In the surface window, select “Register”. Create the surface, only the left plot is updated.

37. Set D to 25 Set the px coefficient to 25.

38. In the surface window, select “Register”. Create the surface, only the left plot is updated.

39. Set D to 80 Set the px coefficient to 80.

40. In the surface window, select “Register”. Create the surface, only the left plot is updated.

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Create the sphere outside the cross. 41. In the surface window select “Surface->so” Set the surface type to “so”.

42. Set R to 99 Set the radius of the outer sphere to 99 cm.

43. In the surface window, select “Register”. Create the surface, only the left plot is updated.

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Add the horizontal beam to the cell description. 44. In the “Surface” window, select “Close” Make the surface window go away, we will not need it

anymore.

45. Select “Cell” from the main menu Get ready to create cell 1 inside the small sphere.

46. Drag across surface 6 Define the four surfaces of the horizontal beam of the cross.

47. Drag across surface 9 Define the four surfaces of the horizontal beam of the cross.

48. Drag across surface 3 Define the four surfaces of the horizontal beam of the cross.

49. Drag across surface 4 Define the four surfaces of the horizontal beam of the cross.

50. Click the mouse at a point inside the four surfaces such as near the center of the sphere

Set the sense for the surfaces of the horizontal beam.

51. Select “Paste” Add the rectangular region to the cell description. Notice the description now shows the four surfaces with the proper sense set for each surface.

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Add the vertical beam to the cell description. 52. Drag across surface 2 Define the four surfaces of the vertical beam of the cross.

53. Drag across surface 5 Define the four surfaces of the vertical beam of the cross.

54. Drag across surface 7 Define the four surfaces of the vertical beam of the cross.

55. Drag across surface 8 Define the four surfaces of the vertical beam of the cross.

56. Click the mouse inside the four surfaces such as near the center of the sphere.

Set the sense for the surfaces of the vertical beam.

57. Select “Paste” Add the rectangular region to the cell description. Notice the description now shows the four surfaces with the proper sense set for each surface. This has been added on to the beam description using a union operator.

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Cut out the inner sphere. 58. Drag across surface 1 Cut out the inner sphere.

59. Click the mouse inside surface 1

Set the sense for the sphere.

60. Select “cut” Remove the inner sphere from the cell description.

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Terminate the Cell at the Outer sphere. 61. Drag across surface 10 Select the outer sphere.

62. Click the mouse outside surface 10

Set the sense for the outer sphere..

63. Select “cut” Terminate the cross at the edge of the sphere in the y direction.

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Create the Cross Cell. 64. In the cell window, select

“Register”. Create cell 2 consisting of the region inside the cross and sphere, but outside the small inner sphere. Notice the outer sphere disappeared because the current view of the geometry does not cut through the outer sphere.

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Create the Region Inside the Sphere, but Outside the Cross. 65. In the right plot, drag across

surface 10. Define the outer boundary of the cell.

66. In the right plot, click inside surface 10 to set the sense.

Set the sense for the outer sphere. We click inside to add the sphere to the cell description.

67. Select “Paste” Add the all inside the outer sphere to the cell description.

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Cut out the Horizontal Beam

68. Drag across surface 6 Define the four surfaces of the horizontal beam of the cross.

69. Drag across surface 9 Define the four surfaces of the horizontal beam of the cross.

70. Drag across surface 3 Define the four surfaces of the horizontal beam of the cross.

71. Drag across surface 4 Define the four surfaces of the horizontal beam of the cross.

72. Click the mouse inside the four surfaces.

Set the sense for the surfaces of the horizontal beam.

73. Select “Cut” Remove the rectangular region from the cell description. Notice the description now shows the four surfaces with the proper sense set for each surface.

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Cut out the Vertical Beam 74. Drag across surface 2 Define the four surfaces of the vertical beam of the cross.

75. Drag across surface 5 Define the four surfaces of the vertical beam of the cross.

76. Drag across surface 7 Define the four surfaces of the vertical beam of the cross.

77. Drag across surface 8 Define the four surfaces of the vertical beam of the cross.

78. Click the mouse inside the four surfaces.

Set the sense for the surfaces of the vertical beam.

79. Select “Cut” Remove the rectangular region from the cell description. Notice the description now shows the four surfaces with the proper sense set for each surface. This has been removed from the sphere using an intersection operator (a space).

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Create the Cell Inside the Sphere, but Outside the Cross.

80. In the cell window, select “Register”

Create the cell inside the sphere, but outside the cross.

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Create the Outside World. 81. In the right plot, drag

across surface 10. Define the outer boundary of the cell.

82. In the right plot, click inside surface 10 to set the sense.

Set the sense for the outer sphere. We click inside to define the region to cut out for the outside world.

83. Select “Cut” Remove the sphere from the cell description, which will define everything but the sphere.

84. Select “Register” Create the outside world cell.

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Save the File

85. Select “File->Save” from the main menu.

Get ready to save the file

86. Enter the file name “isimple”

Enter a name for the file.

87. Select “Save” Save the file.

88. Select “File->Exit” Exit out of the Visual Editor.

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Appendix B In this example you will create 4 cylinders inside a box in Turbo Cad and import the geometry into the Visual Editor. For this example we go through the creation of a perimeter model in CAD for converting to MCNP with the Visual Editor. With perimeter modeling the inside bodies are not subtracted from the outer bodies. The geometry is created from the outside in and only the outside perimeter of the body needs to be modeled. The subtraction of the inner bodies to create the MCNP cells is done the by Visual Editor Conversion code. In steps 3-6 the outer perimeter of the outer box is created, but the inner box is not subtracted. In steps 10-12, the inner box is created as a copy of the outer box. In creating the inner box, only the outside perimeter is modeled and the inside cylinders are not subtracted. The CAD package used for this Example is Turbocad Professional 9.2. Any CAD package that can export SAT files can be used to create this geometry. Most of this exercise describes how to generate a CAD geometry that can be imported into MCNP.

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START TURBO CAD

STEP ACTION DESCRIPTION

1. Start Turbo Cad Bring up Turbo Cad

2. Select NEW FROM SCRATCH

Get ready to create a new file.

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CHOOSE TO CREATE A BOX 3. Change the body type to a box Set the mode to create a box.

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MAKE A CUBE 200 ON A SIDE 4. Set the first vertex to (-100, -100,

-100) PRESS RETURN. You define a box using three vertices.

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MAKE A CUBE 200 ON A SIDE 5. Set the second vertex to (100,

100, -100) PRESS RETURN. You define a box using three vertices.

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MAKE A CUBE 200 ON A SIDE 6. Set the second vertex to (100,

100, 100) PRESS RETURN. You define a box using three vertices.

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CHANGE THE VIEW 7. Set the view to a 3D view. Show the box as a 3D object.

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MAKE A CUBE 14 ON A SIDE 8. Change the mode to SELECT. We want to select the cube just created and make a

smaller copy.

9. Select the cube with a mouse click.

Select the cube so we can make a copy

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COPY THE CUBE 10. Select EDIT->COPY. Copy the cube.

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PASTE THE CUBE 11. Select EDIT->PASTE. Make a copy of the box

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RESIZE THE CUBE 12. Change the size in X, Y, and Z

from 200 to 140. PRESS RETURN.

Resize the new box. If the size buttons do not show up, you need to set the 3D select properties.

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CREATE A CYLINDER 13. Set the mode to cylinder creation Get ready to make a cylinder.

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CREATE A CYLINDER 14. Set the bottom of the cylinder at

(40,40,-70) PRESS RETURN. Set the bottom center of the cylinder. To create a cylinder, you need a bottom base point, a radius point and a height.

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CREATE A CYLINDER 15. Set a point on the radius at:

(65,40,-70) PRESS RETURN. Set the bottom center of the cylinder. To create a cylinder, you need a bottom base point, a radius point and a height.

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CREATE A CYLINDER 16. Set the height to 100.

PRESS RETURN. Set the bottom center of the cylinder. To create a cylinder, you need a bottom base point, a radius point and a height.

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MAKE AN ARRAY OF CYLINDERS 17. Set the mode to SELECT Change to select mode, so we can copy the cylinder

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SELECT THE CYLINDER 18. With the mouse, SELECT the

cylinder by clicking on it. Select the cylinder

19. Select EDIT->COPY ENTITIES->ARRAY

Get set to make an array of cylinders

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CREATE AN ARRAY OF CYLINDERS 20. Set the XSTEP and YSTEP to -

80 Separate the cylinders by 80.

21. Set the ZSTEP to 0. Make the other cylinders at the same elevation.

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CREATE A PLANE AT 30 CM 22. PRESS RETURN, to make the

array Create the array.

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SAVE THE FILE 23. Select FILE->SAVE AS. Bring up the file save dialog

24. Set the SAVE AS TYPE: to SAT Export the file as a SAT file.

25. Set the file type to i4cyl.sat Save the file.

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IMPORT THE FILE INTO THE VISUAL EDITOR 26. Start the Visual Editor Bring up the Visual Editor

27. Select CAD IMPORT->3D IMPORT

Bring up the panel used to import 2D CAD files

28. Select IMPORT. Get ready to read in the sat CAD file

29. Select the file i4cyl.sat and select OPEN.

Read in the 3D cad file

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MAKE ALL OBJECTS TRANSPARENT 30. In the 3D PLOT window, select

MAKE ALL TRANSPARENT This will create the cell (cell 1) which will show up in the plot window.

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CONVET THE FILE 31. In the CAD 3D IMPORT

window, select CONVERT This will convert the CAD geometry.

32. Select INPUT from the main menu.

Bring up a listing of the input file.

33. Select SAVE-UPDATE from the input window.

Reset memory and update the plots.

34. In the right plot, select the SURF toggle button.

Show surface labels.

35. In the right plot, select the CELL toggle button.

Show cell labels.

36. In the right plot, set the top and bottom extents to 200

Expand the view to show the complete geometry.

37. In the right plot, select UPDATE Update the display on the right.

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SAVE THE FILE 38. Select FILE->SAVE AS Bring up the file save dialog.

39. Set the filename to i4cyl and select SAVE.

Set the name and save the file.

40. Select FILE-> EXIT Exit the visual editor.

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