Ishercof

Program ISHERCOF

(21-04-2000)

J.M.J. Journée

This wind resistance prediction method in this program has been described by: R.M. Isherwood,

"Wind Resistance of Merchant Ships",Proceedings of Royal Institution of Naval Architects, 1973.

To run this Fortran/77 program ISHERCOF, the Personal Computer must contain a CONFIG.SYS file with the following statements:

BUFFERS=nnFILES=nnDEVICE=C:\WINDOWS\COMMAND\ANSI.SYS

in which nn is generally 40 or more.For running the program under Windows, this CONFIG.SYS file must be visible in the Explorer. If not so, set in the Explorer: | View | Folder Options | Tab View | Hidden Files | Show all Files |.After these modifications: Restart your computer !!!

Input Data

TEXT Text line with general informationSLOA Length overall (m)B Breadth (m)AL Lateral projected wind area (m2)AS Lateral projected area of superstructure (m2)

If zero: no lateral force for angle of 120-150 degrees AT Transverse projected wind area (m2)S Length of perimeter of lateral projection (m)

(Excluding waterline and slender bodies) C Distance from bow to centroid of lateral projected area (m)M Number of distinct groups of masts or king posts (-)

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Output data

The longitudinal force coefficient is defined by:

The lateral force coefficient is defined by:

The yawing moment coefficient is defined by:

in which:

CX longitudinal force coefficientFX longitudinal forceCY lateral force coefficientFY lateral forceCN yawing moment coefficientN yawing momentRHOA density of airVR RMS of relative wind speed between water level and top of

superstructureAT transverse projected wind areaLOA length overall

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Example of an Input Data File

M.V. HOLLANDIA204.00 30.80 3570 0 756 300.00 115.00 2

Example of an Output Data File

------------------------------------------------------------------------

PROGRAM: ISHERCOF VERSION: 04 APRIL 2000 JOURNEE

CALCULATION OF WIND COEFFICIENTS OF A SHIP ******************************************

DATE: 04-04-2000 TIME: 20:47

------------------------------------------------------------------------

INPUT DATA:***********

M.V. HOLLANDIA

LENGTH OVERALL ................... SLOA : 204.00 meterBREADTH ............................ BR : 30.80 meterLATERAL PROJECTED WIND AREA ........ AL : 3570 sq. meterLATERAL PROJ. AREA OF SUPERSTRUCTURE AS : 0 sq. meterTRANSVERSE PROJECTED WIND AREA ..... AT : 756 sq. meterLENGTH OF PERIMETER ................. S : 300.00 meterDISTANCE FROM BOW TO CENTROID ....... C : 115.00 meterNUMBER OF GROUPS OF MASTS, ETC. ..... M : 2

....LONG FORCE.... .....LAT FORCE.... ....YAW MOMENT....ANGLE OF REL WIND COEFF STAND COEFF STAND COEFF STAND OFF BOW ERROR ERROR ERROR (deg) (-) (-) (-) (-) (-) (-)

0 0.595 0.086 0.000 0.000 0.0000 0.0000 10 0.572 0.104 0.134 0.015 0.0284 0.0048 20 0.592 0.096 0.298 0.023 0.0498 0.0074 30 0.589 0.117 0.451 0.030 0.0536 0.0105 40 0.525 0.115 0.593 0.054 0.0584 0.0137 50 0.367 0.109 0.682 0.055 0.0575 0.0149 60 0.234 0.082 0.732 0.049 0.0432 0.0133 70 0.107 0.077 0.750 0.047 0.0245 0.0125 80 0.044 0.090 0.765 0.046 0.0117 0.0123 90 0.028 0.094 0.737 0.051 -0.0237 0.0141 100 0.014 0.096 0.736 0.050 -0.0490 0.0146 110 -0.046 0.090 0.728 0.049 -0.0690 0.0163 120 -0.148 0.100 -0.0839 0.0179 130 -0.302 0.105 -0.1007 0.0166 140 -0.437 0.123 -0.1057 0.0162 150 -0.523 0.128 -0.1003 0.0141 160 -0.510 0.123 0.274 0.036 -0.0805 0.0105 170 -0.450 0.115 0.119 0.022 -0.0418 0.0057 180 -0.440 0.112 0.000 0.000 0.0000 0.0000

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