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Scholars' Mine Scholars' Mine Masters Theses Student Theses and Dissertations 1963 A study of the angular velocity in a liquid induced by a vortex in an A study of the angular velocity in a liquid induced by a vortex in an emptying container emptying container James Paul Hartman Follow this and additional works at: https://scholarsmine.mst.edu/masters_theses Part of the Mechanical Engineering Commons Department: Department: Recommended Citation Recommended Citation Hartman, James Paul, "A study of the angular velocity in a liquid induced by a vortex in an emptying container" (1963). Masters Theses. 4618. https://scholarsmine.mst.edu/masters_theses/4618 This thesis is brought to you by Scholars' Mine, a service of the Missouri S&T Library and Learning Resources. This work is protected by U. S. Copyright Law. Unauthorized use including reproduction for redistribution requires the permission of the copyright holder. For more information, please contact [email protected].
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Page 1: A study of the angular velocity in a liquid induced by a ...

Scholars' Mine Scholars' Mine

Masters Theses Student Theses and Dissertations

1963

A study of the angular velocity in a liquid induced by a vortex in an A study of the angular velocity in a liquid induced by a vortex in an

emptying container emptying container

James Paul Hartman

Follow this and additional works at: https://scholarsmine.mst.edu/masters_theses

Part of the Mechanical Engineering Commons

Department: Department:

Recommended Citation Recommended Citation Hartman, James Paul, "A study of the angular velocity in a liquid induced by a vortex in an emptying container" (1963). Masters Theses. 4618. https://scholarsmine.mst.edu/masters_theses/4618

This thesis is brought to you by Scholars' Mine, a service of the Missouri S&T Library and Learning Resources. This work is protected by U. S. Copyright Law. Unauthorized use including reproduction for redistribution requires the permission of the copyright holder. For more information, please contact [email protected].

Page 2: A study of the angular velocity in a liquid induced by a ...

A STUDY OF THE A1~GULAR VELOCITY IN A LIQUID INDUCED

BY A VORTEX IN AN EMPTYING CONTAINER

BY

JAMES PAUL HARTMAN (("131-

A

TP£SIS

submitted to the faculty of the

SCHOOL OF MINES AND METALLURGY OF THE UNIVERSITY OF MISSOURI

in partial fulfillment of the work required for the

Degree of

MASTER OF SCIENCE IN MECHANICAL ENGINEERING

Rolla) Missouri

1963

Approved By

(advisor)rAhe9:=tArI~'.~

d:/:#~~~

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ii

AC~~OWLEDGEMENT

The author wishes to express his appreciation to Dr. A. J. Miles,

advisor in this work, and to Mr. B. L. Bramfitt for their valuable

advise and criticism during the course of this investigation. He is

also indebted to Mr. R. D. Smith for his assistance in the construc­

tion of the apparatus.

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iii

ABSTRACT

Previously a limited amount of investigation has been done

to describe the rotational motion of fluid in a draining tank.

To date tank design has been based on trial and error, since the

physical mechanisms of actual draining have not been recognized.

This investigation has been made to devel~p a technique for

the measurement of the motion of the fluid during the draining

process and to present the results of the observed surface velocity

of the liquid as a function of depth of fluid and its distance

from the center of the vortex core.

Many previous investigators of vortex behavior have shown

qualitatively the dynamics of flow, whereas this method of study

was directed at numerical results and practical techniques for

obtaining these results by direct measurement.

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TABLE OF CONTENTS

PAGE

iv

ACKNOWLEDGEMENT ii

ABSTAACT ..• . . . • . . . . . • • •. . . • . . . . • • . . . . . • . . . . . • • . . . . . • • . . • • iii

LIST OF FIGURES . • . . • . . . . • . • . . . . . . . . . . . . • . . . . . . • . . • • • . • . • • v

I. INTRODUCTION AND LITERATURE REVIEW ..•..••.........•.• 1

· II. THE DESIGN AND CONSTRUCTION OF APPARATUS ..•......••• 6

III. EXPERIMENTAL PROCEEDURE AND RESULTS •.•.••.•.....•. 11

IV. CONCLUSIONS AND RECOMMENDATIONS •.•.••.•..•.•.••..•.. 29

V• BIBLIOGRA.PHY • . • • • • • • • • • • • • . . • • . • • • • • • • • . • • • • • • • • • . • • • 32

VI. VITA 33

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v

LIST OF FIGURES

FIGURE

1

2

3

4

Apparatus

Kodak 8 Motion Picture Camera

A Vortex Forming

A Fully Developed Vortex Core

PAGE

7

9

13

14

5 An Oil Droplet On The Surface Of TheRotating Fluid . .. . . . . . . . . 15

6 Curve of Experimental Data At WaterDepth of 1 Inch 17

7 Curve of Experimental Data At WaterDepth of 2 Inches . .. .. .. .. . . .. . .. .. . .. .. . . . . . . . . . . . . .. . . • . 18

8 Curve of Experimental Data At WaterDep th of 3 Inches .. . . . . . . . . . .. . . .. . . . . . . . . . . . . . . . . 19

9 Curve of Experimental Data At WaterDepth of 4 Inches 20

10 Curve of Experimental Data At WaterDepth of 5 Inches .... . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

11 Curve of Experimental Data At WaterDepth of 6 Inclles a .. • • • • .. • • • • 22

12 Curve of Experimental Data At WaterDepth of 7 Inches . . . .. . .. . . .. .. .. .. .. . . 23

13 Curve of Experimental Data At WaterDepth of 8 Inches . . . . . .. . . . . . . . .. . . 24

14 Curve of Experimental Data At WaterDepth of 9 Inches ... . . . . . . . . . . .. . . . . . . . . . . . . . . . . . 25

15 Curve of Experimental Data At WaterDepth of 10 Inches ...........................•.. 26

16 Relief Of The Angular SurfaceVelocity Of A Vortex 27

Page 7: A study of the angular velocity in a liquid induced by a ...

1

I. Il\TTRODUCTION ~-n LlTER..4.TlJRE REVIE1\T

When a tank containing a liquid is drained by means of an

outlet located on the bottom, a phenomenon occurs which is kno\Vfi

as vortexing. This action of the liquid can readily be observed,

but the understanding of the vortexing motion of the liquid is

still unexplained in its entirety.

Of the various liquid dynamic phenomena that may occur in a

tank, the rotational motions of the liquid are of special interest

because of the torque exerted on the tank through viscous action

of the, fluid, changes in inertial distribution, and reduction

in flow rate during tank draining as a result of vortex formation.

The general study of vortices may in part give additional

insight and information concerning these problems of liquid rotation,

vortexing, and draining.

Most of the work that has been done in search for an explana­

tion of the rotational motion has been mathematical analyses of

the physical properties of the vortex and its surroundings. Even

these studies are made with assumptions of ideal and unreal

condi tions.

Over a century ago Helmholtz (1) published his well-known

paper on vortex motion. He established three basic theorems for

this type of motion. The main content of these theorems were

the conservation laws. He stated first that it is i~possible to

produce or destroy vortices, or, expressed in more general terms,

the vortex strength is constant in time. Then he proposed that

the vortex strength is constant along each vortex line or vortex

Page 8: A study of the angular velocity in a liquid induced by a ...

2

tube. His third theorem stated that the circulation is the same

in all circuits embracing the same vortex tube.

Helmholtz studied the application of these theorems to

certain practical cases) such as the interaction between several

parallel vortices, the behavior of a vortex in the neighborhood

of a fixed boundary, vortex sheets, and circular vortices.

Later~ Lord Kelvin (2) added as a fourth theorem on vortex

motion the fact that the circulation around a vortex core is

constant and may serve as a measure for the strength of a vortex.

Probably one of the more complete surrmarys of vortex behavior

has been written by Lamb (3) as he has given a fairly complete

survey of the work done in the field up until the publication of

his book. Although very few new developments were presented in

his writings, this was the last complete publication that has

taken into account all of the general aspects of vortices.

Recent studies have been made on specialized cases of vortex

behavior, such as Oseen (4)) who found a solution to the vortex

problem which explains the decay of vortices. The same solution

was found by other scientists from an analogy of the vortex motion

to certain problems concerning t~e diffusion of heat.

Shapiro (5) has systematically defined rotational flow and

shown the connection between the rotation and the thermodynamic

properties of the flow. The stagnation enthalpy, ho ' is related

to the velocity and enthalpy through the steady-flow energy relation,

h = h + v 2o 2

Page 9: A study of the angular velocity in a liquid induced by a ...

3

or differentiating \vith respect to the radial direction,

\ 1 d t, dVCJ i~ 0 - ..--.- -.- V-~d \'\

h d nThe thermodynamic relation for the entropy is

Tds --- dh I--- clp

This too may be' expressed in derivative form as

d {~ T d'S .J-}p- -- • F dr.d~ d h

dP T d'S +.0 ~hoJ \t1 - - P d h I -J \'\

Substituting this'into Euler's equation for rotation

The combination of these two thermodynamic equations then yields

dV-:!'V ~

2 w -dV

Shapiro has obtained an expression relating the rotation. of the

fluid to the change of the thermodynmaic prop~r~~2s of the fluid

.?w.......n---v

....CiS

In his aerivation of an equation for vortex ffiJLion in a two-

dimensional incompressible fluid,'Dryden (6) has searched for an

exact solution without neglecting the inertia terms, as is often

done in such solutions to make the equations linear. Although

the inertia terms complicate the problem somewhat, Dryden has

sho'\vu that they must be included for the exact solution of the

vortex motion problem.

l:eufville ~7) has attempted to correct SOUle 0:"": the s·b.ort-

comings of HelIT~oltz's vortex theory with the use of the Navier-Stokes

Page 10: A study of the angular velocity in a liquid induced by a ...

4

Equations. With the use of these equations) he has been able

to present a set of solutions for axial s~~etrical plane vortex

motion. These solutions explain why the vorticity in a Helmholtz

vortex slowly diffuses to infinity) so that in a finite region the

fluid finally comes to rest. Neufville 1 s investigation has

indicated the need for a re-evaluation of the whole vortex problem

in viscous fluids) including the related solutions and theorems

available at present.

Though studying compressible fluid flo\v) Pai (8) has derived

equations of the minimum radius for a vortex core which can be

applied to incompressible fluids. These equations were based on

Kelvin 1 s Theorem that in a frictionless) homogeneous fluid without

body forces the circulation along a closed fluid line remains

constant with respect to time.

Dergarabedian (9)) in a recent investigation) has gone to

great lengths to derive the velocity components of a vortex system.

Because of the intractable nature of the problem) many assumptions

were made and the resulting answers were more n~arly of a

qualitative nature) rather than exact solutions.

A motion picture edited by Shapiro (10) reviews vorticity

. in general~ It was based on experimental demonstrations of phenomena

relating vorticity to circulation) and to the theorems of Crocco)

Kelvin, and Helmholtz.

More recently, Abramson, Chu, Garza, and Rans1eben (11) have

presented the results of some experimental and theoretical studies

of vortex formation while draining fluid from cylindrical tanks,

and related liquid dynamic behavior. The experimental studies

Page 11: A study of the angular velocity in a liquid induced by a ...

5

were largely visual, through motion picture films. An analytical

study of vortex formation in cylindrical tanks was also presented

in an attempt to understand and delineate better the flow mechanisms

involved. Also included were some data on time required for draining

with various fluids, tank bottom shapes, and slosh and vortex

suppression devices.

As a further attempt to understand better the basic mechanisms

involved in vortex behavior in draining tanks, this investigation

has developed a technique for the direct measurement of the angular

surface velocity of the fluid surrounding a vortex core, and

studies may be made of the vortex by using this method.

A study of vortex behavior is necessary to understand the

details of tank draining which may be applied to tank and orifice

designs.

Page 12: A study of the angular velocity in a liquid induced by a ...

6

II. THE DESIGN A1~ CONSTRUCTION OF APPARATUS

The apparatus used in this experiment was basically a large

.cylindrical tank with an orifice in the center of its bottom) and a

system of devices to place an oil droplet at a predetermined point

on the surface of the fluid being drained from the tank) and finally

means to record the dynamic behavior of the droplet as it follows'

the moving fluid.

Figure 1 shows the flat-bottomed tank which was constructed

of 22 gauge galvanized sheet steel) with inside dimensions of 48

inches in diameter and a depth of 16 inches. Located on the bottom

of the center of the tank was an outlet of 1 inch diameter. This

ratio of tank diameter to orifice diameter was large enough to

eliminate the boundary layer effects caused by the walls for a

study of the vortex core and the fluid motion in its immediate

vicinity.

A gate valve was located directly beneath the drain outlet and

was operated by an extended stem which lets the valve manipulation

be made from the control table. A gate valve was favored for this

experiment because of its straight line flow design with a minimum

of valving fluid friction. The elongated valve stem was connected

to the valve using a neoprene universal joint and the stem was

supported rigidly by the tank support assembly~ This combination

gave a vibration-free operation of the valve necessary to insure

any unnecessary disturbance of the fluid in the tank. From the

valve) the draining fluid was directed through a flexible 2 inch

reinforced rubber hose.

Page 13: A study of the angular velocity in a liquid induced by a ...

Figure 1

APPARATUS

MAY • 63

7

Page 14: A study of the angular velocity in a liquid induced by a ...

8

The appar~tus to place the oil droplet on the moving water­

surface consisted of a leg set on each side of the tank constructed

of 1 inch angle iron and \Vere connected to one another by avO round

1/2 inch hollow steel tubes. These tubes served not only as braces

for the rigid system) but acted as burette clamp guides for the

horizon positioning of the burette containing the oil.

For the precise adjusting of the burette) the burette clamp was

attached to a threaded solid steel rod which parallels the brace

rods. This ~l. .. readed rod had 28 threads per inch arld \Vas rotated by

a 1/15 horsepower General Electric AC-DC electric motor that had

a rewired armature to provide for reversal of shaft rotational

direction. By this means) the burette was displaced 1/28 inch

horizontally per motor revolution. On the opposite end of the

threaded shaft) above the control table) a counter was employed to

enable the investigator to maintain an exact control on the positioning

of the burette. The motor speed was regulated by a Superior Electric

Company 0-135 volt powerstat that varied the armature and field

voltage input. .~lso on t11e control table was a two-way switch that

reversed the armature currenL for reverse rotation of the motor.

A permanent record of the oil droplet behavior once it had

been placed on the surface of the rotating fluid was accomplished

by means of a Kodak 8 motion picture camera (Figure 2). This caw£ra

uses an 8 millimeter film and photographs 16 pictures per second.

The photoelectric exposure meter which automatically set the exposure

time for the shutter was ideal for this experiment inasmuc~~ as the

reflections from the oil droplet change constantly from the ever

changing position of the droplet.

Page 15: A study of the angular velocity in a liquid induced by a ...

Figure 2

KODAK 8 MOTION PICTURE CAMERA

9

Page 16: A study of the angular velocity in a liquid induced by a ...

10

The camera was firmly mounted above the tank from an adjustable

tripod constructed of 1 1/2 inch angle aluminum. The camera release

was activated by the investigator with a cord attached to a lever

arm which was an intergal part of the tripod mounting.

Two General Electric 150 watt white floodlights provided the

illumination.for the photography. This was only 1/2 the amount of

light recommended by the manufacturer of the Kodak Type A indoor

film used in the investigation) but because of reflections from the

bottom of the tank) this was the most satisfactory light combination

for photography of the rotating liquid.

It was found that SAE 90 outboard motor gear lubricant was the

most suitable oil for use as the tracer. This type of oil was very

insoluble to water and the dull blackish-green color was especially

photogenic.

Page 17: A study of the angular velocity in a liquid induced by a ...

11

III. EXPERI}ffiNTAL PROCEDURE A1~ RESULTS

The experimental procedure used in the determination of the

angular surface velocity around a vortex core in an emptying tank

with the apparatus previously described was one of finding the

most accurate and reliable method possible.

The most important consideration that must be respected \Vas

the ability to place the oil droplet traced in the rotating fluid

at a precise point and reco~ding the dyn&ilic action instantly

at that position and i~~ediately aftenvards. Inasmuch as the

water level of the draining tank changes very slo\vly, th2 problem

of positioning the droplet at a predetermined water level was small.

This was accomplished simply by watching a calibrated scale on

the inside of the tank. As the surface of the water draining from

the tank reached a level on the scale in which a velocity measure­

ment was desired, an oil droplet was released and a recording made

on the camera.

On the other hand, the locating of the tracer at a fixed horizontal

distance from the center of the vortex core required a static

structure with a means to adjust the radius of the burette from the

center of the tank. Before the start of an experimental run the

position of the burette was determined, hence throughout the run the

horizontal position could be changed with the motor that was attached

to the threaded rod on which the burette cla~p was carried. By

counting the revolutions turned by the threaded rod, an exact

position of the burette- was always kno\VU.

To begin a run, the tank was completely filled to the 16 inch

Page 18: A study of the angular velocity in a liquid induced by a ...

12

depth mark and allowed to settle until the visually apparent sloshing

motion had ceased. Since the tank was al'\vays filled in a counter­

clockwise direction with r2spect to an observer looking do'\vu into

the tank, a small initial angular velocity was apparent at the

beginning of an experimental run. The only effect this initial

velocity had on the vortex behavior was to hasten the forming

of the vortex core. The velocity of the rotation caused by the

vortex was many times stronger than the initial rotation. This was

observed by recording the angular surface velocity at a particular

point with various initial velocities of the water. These velocities

did not vary an appreciable amount 0

After the lateral oscillations had ceased in the fluid, the

valve on the outlet of the bottom of the tank was opened, allowing

the water to start draining. As the water level began to fall,

the rotational motion of the liquid began to acoelerate and the

vortex core started to form on the surface of the water. In the

same manner, the core lengthened until it reached the mouth of the

outlet on the bottom of the tank (Figures 3 and 4). Immediately the

flow of water from the tank was reduced by over 75 per cent.

~ormal1y the vortex core was completely developed by the time the

water level had fallen to 14 inches. To allow the rotation of the

fluid surrounding the core to become stabilized and to become a

complete function of the vortex strength, data was not recorded

until the water depth had fallen to 10 inches. At this level an

oil droplet (Figure 5) was released from the burette and a photo­

graphi~ recording was taken of its rotational displacement. As the

Page 19: A study of the angular velocity in a liquid induced by a ...

Figure 3

A VORTEX FORMINr

• MAY • 6:=',

13

Page 20: A study of the angular velocity in a liquid induced by a ...

Figure 4

A FULLY DEVELOPED VORTEX CORE

• MAY • 63

14

Page 21: A study of the angular velocity in a liquid induced by a ...

Figure 5

AN OIL DROPLET ON THE SURFACE OF THE ROTATING FLUID

MAY • 63

15

Page 22: A study of the angular velocity in a liquid induced by a ...

16

water level dropped to 9 inches) a similar procedure was followed.

In a like manner) recordings \Vere made at one inch increments of depth

to the bottom of the tank. Then the burette was moved to a different

radius from the center of the tank and the procedure followed again.

Thre2 experimental runs 'Ylere made for each position in 'tvhich

the rotational velocity was desired.

Due to the fact that the top of the vortex core was rounded)

there was a limit to the minimum radius in which the surface velocity

could be calculated.

With the use of a slide projector dnd a special slide that

allowed the man~al projection of individual frames from the films

of the oil droplet movement, the position of the rotating fluid

was determined at 1/16 second intervals. To calculate the angular

velocity of the fluid at a particular position, sixteen consecutive

frames of the oil droplet were recorded on the projection screen.

The angular velocity can be measured o~rectly in degrees per second.

This procedure involvea the revie\ving of approximately 16,000

pictures for the three runs that were recorded.

From the data, which is graphically illustrated on Figures 6

through 15, it was apparent that the angular velocity of the fluid

increased exponentially toward the core of the vortex. It was also

apparent from this data that at distances from the center of the

vortex core greater than 5 inches there was an almost linear relation­

ship for the decrease in angular surface velocity at all flLid

depths. This was ShOvffi even better on Figure 16, a relief ct

the angular surface velocity as a function of the deptli of \'later

and the distance from the vortex core. Calculations by Dergarabedian

Page 23: A study of the angular velocity in a liquid induced by a ...

TIGLE 1

EXPERI1!IE1'IT1\L D.:\.TAY. r. -', ....

..J ..\i

Radius (Inches)Depth (Inches) 1.0 1.5 2.0 2.5 3.0 4 0 5.0 6.0 8.0 10.0

10

9

8

7

6

118011351160

97910211032

904872911

791772763

649603640

6.-754iO480

42042L~

L:-02

35233334-5

270275275

2232 ') ,

->.1.

225

300293298

2502L:-6260

221225216

191216

150163174

162160166

153147146

128132132

118117115

100102105

80,) r-:

0,)

89

SO8179

707Lr­75

606765

596056

575760

525366

49L~ 950

474545

414236

282730

I)r

.::.LJ

2626

253027

252Lt­24

262223

21.022.022.0

20.)20.020.5

18.018.018.5

17.517.017.5

17.016.516.5

510 203 138

'ju

90

J1.

51 33

LL

22

.LO.U

16.0

4

3

2

L~CO 175 115L;·03 177 1173S6 170 110

430* 302 160 99410* 255 166 101425* 280 158 96

J~U 210 l~O 89360 215 134 88360 220 128 83

707L~

73

685960

4SL!_L:_

45

7

36

30

27

303029

2728

21 16.021 15.520 15.0

20 15.020 15.019 17.0

20 -, L:_ 5') 14.5

_.J 13.0

1 360 225352 220355 225

150 110175 116165 112

817880

302930

2L~

23202222

13.014.0

18 15.0

NOTE: * R = 1.75

Page 24: A study of the angular velocity in a liquid induced by a ...
Page 25: A study of the angular velocity in a liquid induced by a ...

f ~gur.~._. 7 : _~ __ .._._ _ __..__ ..___ _.._..__._':'.; _.. .

Page 26: A study of the angular velocity in a liquid induced by a ...
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Page 29: A study of the angular velocity in a liquid induced by a ...
Page 30: A study of the angular velocity in a liquid induced by a ...

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28

(9) have sho"m that the center of the core has a theoretical

angular velocity of infinity. The data which had been taken from

the rotating fluid surrounding the core has given evidence that

this may very well be true.

Figure l6 r indicated the angular surface velocity to be a

linear function of the water depth, except at shallow water depths.

This non-linear-variation \vas no doubt caused by the boundary layer

effects of the tank bottom) as described by Rohsenow and Choi (12).

They have derived an exact solution for boundary layer thickness

over a flat plate) \vhich has shown the thickness as an exponential

function of the linear velocity of the fluid. Since the velocity

of the fluid increased toward the center of the vortex core) the

thickness of the boundary layer increased in a like manner. Be­

cause of the turbulence of the boundary layer, experimental results

of the angular surface velocity at water depths below 1 inch could

not be considered reliable.

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29

IV. CONCLUSIONS Al'ID REC01:frfE1iDATIONS

The apparatus designed and used in this experimental investigation

performed favorably in the measurement of the angular surface velocity

of the vortex environment. Of the tests made at various \Vater levels}

consistent results \-lere obtained except near the bottom of the tanl<

where the boundary layer turbulence had a tendency to scatter the 'oil

drops. Othenvise} the results in the laminar flow region seemed

to be very reliable.

A difficulty that sometimes arose with the use of this apparatus

was the tendency for the liquid to slosh. This was usually caused

by some outside influence such as the vibration of other machinery

in the laboratory. With a vibration-free environment) the vortex

core was surprisingly stable. This in itself remains a large problem

in the science of tank drainage as many vortex suppressors are

ineffective because of the strong tendency of a liquid to form a

vortex.

Though it is obvious that this analysis does not constitute

anything like a complete description of the three-dimensional flow

velocities) it was believed that the results show possibilities. for

adaptation and use in a more complete investigation of the behavior

of the vortex.

With the use of the technique described previously} a complete

study of boundary layer effects for various sized tanks should

be possible. Not only could the tanks be dimensionally different}

but they might be of' different geometric design. These parameters

will change the flow patterns considerably.

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30

Along with the various sized tanks) the change in drainage

outlet dimensions and the shape of the outlet is reco~~ended for

further studies. For this experiment a I inch round hole was located

in the center of the tank. It is believed that an orifice that will

constantly induce turbulence at the base of the vortex might tend

to eliminate the entire core.

More studies might be made on the effects of the initial

rotation of the liquid. This would require a tank similar to the

one used in this experiment mounted on a table that could be rotated

at known angular velocities. Naturally induced vortices may be

eliminated by canceling the forces that cause them.

Another recommendation for the experimental tank design is to

develop a method to replace the water in the 'tank as fast as the

water is drained without disturbing the vortex or its immediate

environment. This would require a tank boundary very far from the

drainage outlet. One method that is thought to be feasible for this

particular operation is to have the test tank contained in another

tank of slightly larger radius. The entire side of the test tank

would be perforated with small holes so that water could be added to

space between the two tank walls and would then flow through these

holes into the test tank, keeping the water level constant. This

type of apparatus would be very helpful for two-dimensional flow

studies~

A fina; recommendation would be to make a study of the vortexing

of boiling liquids. In present day rocket engine design) this is a

problem with the fuel· tanks containing the c~yogenic fuels. As the

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31

liquid boils flow patterns are believed to change greatly.

The recommendations indicated are not meant to be a necessity,

but are offered as a means to enable further vortex studies, in hope

that a better insight may be derived on the various problems. With

the technique developed in this investigation, the vortex behavior

may be inspected very efficiently in any open tank.

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32

V. BIBLIOGRAPHY

1. HELMHOLTZ, H. (1858) Uber Die Integrale Der HydrodynamischenGleichungen, Welche Den Wirbelbe\vegungen Entsprechen.Journal Fur Die Reine Dnd Ange Wandte Mathematik - Vol. 55.Translated into English by Professor Tait, (1867)Philosophical Magazine, Vol. 33, Series 4.

2. THOMSON, SIR W. (Lord Kelvin) (1869) On Vortex Motion.Translations of the Royal Society of Edinburgh, Vol. 25.Reprinted in Mathematical and Physical Papers, Vol. 4,Camb~idge (1910).

, 3. LAMB, H. (1895) Hyrodynamics. Cambridge University Press,Cambridge, P. 22-265.

4. OSEEN, C. W. (1927) Neuere Methoden and Ergebnisse in DerHydrodynamik. Leipzig P. 86.

5. SHAPIRO, A. H. (1953) The Dynamics and Thermodynamics ofCompressible Fluid Flow. Ronald, New York P. 267-283.

6. DRYDEN, H. L. (1956) Hydrodynamics. Dover, New York, P. 223-232

7. NEUFVILLE, A. D. (1957) The Dying Vortex. Proceedings of theFifth Midwestern Conference on Fluid Mechanics. Universityof Michigan Press, Ann Arbor.

8. PAl, S. I. (1959) Introduction to the Theory of CompressibleFlow. D. Van Nostrand, New York, P. 79-84.

9. DERGARABEDIAN, P. (1960) The Behavior of Vortex Motion in anEmptying Container. Proceedings of the 1962 Heat Transferand Fluid Mechanics Institute.

10. SHAPIRO, A. H. (1962) Vorticity (Film). National Committee forFluid Mechanics Films.

11. ABRAMSON, H. N., CHU, W. H., GARZA, L. R. AND RANSLEBEN, G. E.(1962) Some Studies of Liquid Rotation and Vortexing inRocket Propellant Tanks. NASA TN D-1212, National Aero­

nautics and Space Administration, Southwest Research In­stitute, San Antonio, Texas.

12. ROHSENOW, W. M. AND CHOI, H. Y., (1961) Heat, Mass and MomentumTransfer. Prentice-Hall P. 24-30.

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VI. VITA

The author, James Paul Hartman, was born on June 21, 1937 in

Hannibal, Missouri. He received both his primary and secondary

education in· the public school in the same city, and his college

education from the University of Missouri School of Mines and

Metallurgy, Rolla, Missouri. A Bachelor of Science Degree in

Mechanical Engineering was received from the University in May of

1959. Following graduation he was called to the services of the

United States Army. After a tour of duty with the Army, he was

employed by Lockheed Aircraft Corporation, Burbank, California. In

February of 1962, he was granted a leave of absence by his employer

to pursue his studies toward a Master of Science in Mechanical

Engineering at the University of Missouri School of Mines and

Metallurgy.

33