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I I
ENGINEERING AND INDUSTRIAL RESEARCH STATION
Quarterly Progress Report #9
NAS8-11334
RESEARCH STUDY FOR DETERMINATION OF LIQUID SURFACE PROFILE
IN A CRYOGENIC TANK DURING GAS INJECTION
June 18, 1966 - September 17, 1966 6
GPO PRICE s COLLEGE OF ENGINEERING CFSTl PRICE(S) $
N 0 I -937 (ACCESSION NUMBER) - (THRUI
e Hard copy (HC)
Microfiche (MF) /
I
i ff 663 July 66
-
MISSISSIPPI STATE UNIVERSITY STATE COLLEGE, MISSISSIPPI
https://ntrs.nasa.gov/search.jsp?R=19670003603 2020-05-16T14:47:53+00:00Z
I 1'
Engineering and I n d u s t r i a l Research S t a t i o n College of Engineering
Miss i s s ipp i S t a t e Univers i ty P.O. Drawer PE, S t a t e Col lege, M i s s i s s i p p i 39762
@ a r t s r l y Progress Report 89, ??AS8-11334 RESEARCH STUDY FOR DETERMINATION OF L I Q U I D
SURFACE PROFILE I N A CRYOGENIC TANK DURING GAS INJECTION
Per iod Covered: June 18, 1966 - September 1 7 , 1966
Authors :
D r . Wm. D. McCain, Jr. D r , E. H. Bishop Mr. James T. Smith
Quar te r ly Progress Report Contract Number: NAS8-11334 Control Number: DCN 1-4-50-01218-01 (1F)
CPB 02-1277-64
This r e p o r t w a s prepared by M i s s i s s i p p i State Univers i ty under NAS8-11334
RESEARCH STUDY FOR DETERMINATION OF L I Q U I D SURFACE PROFILE I N A CRYOGENIC TANK
DURING GAS INJECTION, For t h e George C. Marshal l Space F l i g h t Center of t h e
National Aeronautics and Space Administration. The work w a s adminis tered under
t h e t e c h n i c a l d i r e c t i o n of the Propuls ion and Vehicle Engineering Laboratory,
of t h e George C. Marshal l Space F l i g h t Center wi th M r . Hugh M. Campbell a c t i n g
as p r o j e c t manager.
. iii
. TABLE OF CONTENTS
Page LIST OF FIGURES . . . . . . . . . . . . . . . . . . . . . . . iv LIST OF TABLES . . . . . . . . . . . . . . . . . . . . . . . . vi INTRODUCTION . . 1
ANALYSISOFPROGRESS. . . . . 1
PROGRESS.. . . . . . . . . . . . . . . . . . . . . . . . . . 2
Surface Profile . . . . . . . . . . . . . . . . . . . . 2
Entrainment . . . . . . . . . . . . . . . . . . . . . . 3
Flow Characteristics . . . . . . . . . . . . . . . 16 Entrainment Rates . . . . . . . . . . . . . . . . . 19
CURRENT PROBLEMS . . . . . . . . . . . . . . . . . . . . . . . 24
PLANS' FOR NEXT QUARTER . . . . . . . . . . . . . . . . . . . . 2 4
AF'PENDIXI.. . . . . . . . . . . . . . . . . . . . . . . . . 25
',
c
.
LIST OF FIGURES
Figures
1.
2.
3.
4.
5 .
6 .
7.
8.
9.
Page
Comparison of Surface P r o f i l e Data f o r t h e 18" and 5' Bubble Tanks a t a Dimensionless Radial Coordinate, r = 0.0. Nitrogen Gas i n D i s t i l l e d Water.. . . . . . . . . . . . . . . . . . . . . . . . . . 5
Comparison of Surface P r o f i l e Data f o r t h e 18" and 5' Bubble Tanks a t a Dimensionless Radial Coordinate, r = 0.25. Nitrogen Gas i n D i s t i l l e d Water.. . . . . . . . . . . . . . . . . . . . . . . . . . 6
Comparison of Surface P r o f i i e "uta f o r the 18" and 5' Bubble Tanks a t a Dimensionless Radia l Coordinate, r = 0.50. Nitrogen Gas i n D i s t i l l e d Water.. . . . . . . . . . . . . . . . . . . . . . . . . . 7
Comparison of Surface P r o f i l e Data f o r t h e 18" and 5' Bubble Tanks at a Dimensionless Radia l Coordinate, ~ 0 . 7 5 . Nitrogen Gas i n D i s t i l l e d Water.. . . . . . . . . . . . . . . . . . . . . . . . . . 8
Comparison of Maximum Surface P r o f i l e f o r t h e 5' and 18" Tanks. Nitrogen Gas i n D i s t i l l e d Water.. . . . . . . . . . . . . . . . . . . . . . . . . . 9
Comparison of Surface P r o f i l e Width Data f o r t h e 5' and 18" Tanks. Nitrogen Gas i n D i s t i l l e d Water.. . . . . . . . . . . . . . . . . . . . . . . . . . 10
Non-dimensional Sur face P r o f i l e Z/Zr,o, ve r sus Dimensionless Radial Coordinate r , f o r t h e D i s t i l l e d Water-Nitrogen System. . . . . . . . . . . . . . 11 Comparison of Surface P r o f i l e Cor re l a t ion wi th t h e Experimental P r o f i l e i n Water Caused by a Rising Swarm of Nitrogen Bubbles a t an Overall I n l e t Gas Flow Rate of 12.36 Standard Cubic Fee t Per Hour from a Square Configurat ion of Nine Hypodermic Needles. . . . . . . . . . . . . . . . . . . . 12
Comparison of Surface P r o f i l e Cor re l a t ion wi th t h e Experimental P r o f i l e i n Water Caused by a Rising Swarm of Nitrogen Bubbles a t an Overall In le t Gas Flow Rate of 19.55 Standard Cubic Feet Pe r Hour from a Square Configurat ion of Nine Hypodermic Needles.. . . . . . . . . . . . . . . . . . . . 13
I I .
4
LIST OF FIGURES -- continued 10. Comparison of Surface Profile Correlation with the
Experimental Profile in Water Caused by a Rising Swarm of Nitrogen Bubbles at an Overall Inlet Gas Flow Rate of 21.55 Standard Cubic Feet Per Hour from a Square Configuration of Nine Hypodermic Needles. . . . . . . . . . . . . . . . . . . . . . . . . . .14
11. Comparison of Surface Profile Correlation with the Experimental Profile in Water Caused by a Rising Swarm of Nitrogen bubbles at an Overall Inlet Gas Flow Rate of 23.70 Standard Cubic Feet Per Hour from a Square Configuration of Nine Hypodermic Needles. . . . . 15
12. Entrainment Test Section . . . . . . . . . . . . . . . . . 17 13. Entrainment versus Time for the Configuration
Shown in Figure 12 (1/2 Filled, 5-fOOt Horizontal Pipe) for Various Air Flow Rates and Viscosities . . . . . 21
14. Entrainment versus Time for the Configuration Shown in Figure 12 (1/4 Filled, 5-FOOt Horizontal Pipe) for Various Air Flow Rates and Viscosities . . . . . . . . . . 22
Y
v i
LIST OF TABLES
Table Page
I. Experimental Sur face P r o f i l e s Obtained Through Use of t h e Five-foot Square Bubble Tank. D i s t i l l e d Water Nitrogen System.. . . . . . . . . . . . . . . . . . . . . . . 4
11. Entrainment Versus T i m e f o r T e s t Sec t ion Shown i n F igure 12(1/4-Fi l led) f o r Various A i r Flow Rates and Liquid V i s c o s i t i e s . . . . . . . 26
111. Entrainment Versus T i m e f o r Test Sec t ion Shown i n Figure 1 2 (1/2-Fi l led) fnr Various A i r Flow Rates and Liquid V i s c o s i t i e s . . . . . . . . 27
a
INTRODUCTION
This is t h e n i n t h Quarter ly Progress Report f o r NAS8-11334,
RESEARCH STUDY FOR DETERMINATION OF L I Q U I D SURFACE PROFILE I N A
CRYOGENIC TANK DURING GAS I N J E C T I O N .
18, 1966 t o September 1 7 , 1966.
The per iod covered is June
ANALYSIS OF PROGRESS
A l a r g e r bubble tank was cons t ruc ted and t e s t e d t h i s qua r t e r .
As t h e t o t a l gas flow rate was increased the s u r f a c e waves i n the
previous eighteen-inch square tank splashed aga ins t t h e walls and
obscured t h e view of t h e su r face d is turbance . A new tank f i v e - f e e t
square was cons t ruc ted .
t h a t of previous d a t a were obtained.
t o the prev ious c o r r e l a t i o n s . Thus, i t appears t h a t t h e new tank
can be used t o extend t h e e x i s t i n g c o r r e l a t i o n .
Data i n a flow rate region which over laps
The new d a t a f i t very c l o s e l y
The entrainment phase of t h i s research during t h e p a s t q u a r t e r
w a s d i r e c t e d t o a s tudy of the in f luence of t he entrapped-l iquid
v i s c o s i t y on entrainment of the l i q u i d by a i r streams.
s e c t i o n s u t i l i z e d i n t h e water tests are being used f o r t h e v a r i a b l e
v i s c o s i t y tests. From t h e l imi t ed d a t a co l l ec t ed t o d a t e c e r t a i n
t r e n d s are ind ica t ed , however, a d d i t i o n a l tests are requi red before
any d e f i n i t e conclusions may be drawn regarding t h e r o l e of l i q u i d
v i s c o s i t y i n entrainment. P l o t s of entrainment versus t i m e f o r
v a r i o u s average a i r mass flow rates and l i q u i d v i s c o s i t i e s are pre-
s en ted and discussed i n t h i s repor t .
The same test
These p l o t s are explained i n
*
terms of t h e l i q u i d flow c h a r a c t e r a t i c s i n va r ious p a r t s of t h e
test s e c t i o n , and comparisons of t h e s e c h a r a c t e r i s t i c s are made
wi th those of water which are thoroughly descr ibed and d iscussed
i n Annual Report 112.
a i r mass flow rates ( g r e a t e r than 6.66 lbm/min) f o r t h e v i s c o s i t y
range of lcp-4cp changes i n v i s c o s i t y have very l i t t l e e f f e c t upon
entrainment.
a i r flow rates inc reases i n v i s c o s i t y cause s i g n i f i c a n t reduct ions i n
entrainment.
The i n i t i a l r e s u l t s i n d i c a t e t h a t a t high
However, a t low t o medium (4.11 lbm/min t o 6.66 lbm/min)
PROGRESS
Surface P r o f i l e
The Second Annual Report, dated June 18, 1966, g ives t h e
he igh t and shape of t he su r face p r o f i l e s caused by r i s i n g swarms
of gas bubbles as determined experimentally.
i n l e t gas flow rate of from 2 t o 28 s tandard cub ic f e e t pe r hour.
Cor re l a t ions of t h e s e d a t a were a l s o presented, which could 5e used
t o compute t h e shape of t h e d is turbance f o r any i n l e t gas flow ra te
i n t h a t range. A t t h e h igher gas flow rates w e began t o experience
d i f f i c u l t y i n ob ta in ing d a t a i n t h e 18-inch square tank then being
used. Sur face waves caused by t h e d is turbance would sp la sh aga ins t
t h e s i d e s of t h e tank obscuring the s u r f a c e p r o f i l e s . Consequently,
i t w a s determined t h a t a larger tank would have t o be b u i l t i n order
t o permit ex tens ion of t h e i n l e t gas flow rate t o h igher rates.
The primary e f f o r t t h i s q u a r t e r w a s devoted t o designing,
The new tank is
The d a t a cover an
cons t ruc t ing and t e s t i n g a l a r g e r bubble tank.
- 2 -
*
c f ive - f ee t square and approximately t h r e e f e e t i n depth wi th t h e
gas i n l e t device loca t ed i n the center .
square tank f o r photographic cons idera t ions , and P lex ig l a s w a s
used as t h e material of cons t ruc t ion . The f i r s t cons ide ra t ion w a s
whether t h e d a t a obta ined using t h e new tank would agree wi th t h e
previous d a t a obta ined with the smaller tank and would f i t t h e
previous c o r r e l a t i o n s . Therefore, t h e f i r s t f o u r su r face p r o f i l e s
were obta ined a t gas flow rates between twelve and twenty-four
s tandard cubic feet per hoiir, vhkh fall w i t h i n the range pre-
v ious ly s tud ied .
a long wi th t h e earlier d a t a as presented i n f i g u r e s 46 through 51
of t h e Second Annual Report. It may be seen t h a t t h e d a t a obta ined
through use of t h e l a r g e r tank does f i t w e l l wi th the earlier data.
The a d d i t i o n of t h i s d a t a , presented i n Table 1, has no t changed t h e
gene ra l i zed non-dimensional su r f ace d is turbance shape, which w a s
p resented as Figure 44 i n t h e Second Annual Report , and is repeated
here as Figure 7. Figures 8 through 11 give comparisons of t h e new
d a t a wi th t h e c o r r e l a t i o n s given i n Figures 7 , 1, and 6.
We have aga in used a
Figures 1 through 6 show t h e f o u r new d a t a p o i n t s
Entrainment
The primary e f f o r t during t h i s r e p o r t per iod w a s devoted t o
i n i t i a t i n g a s tudy of t h e i n f h e n c e of t h e v i s c o s i t y of an entrapped
l i q u i d on t h e removal of t h i s l i q u i d by an a i r stream.
Viscos i ty v a r i a t i o n w a s accomplished by us ing va r ious mixtures
of g l y c e r i n e and water.
dependent and s i n c e t h e a i r stream temperature o f t e n varies from 10'
t o 15'F i n t h e course of a day's opera t ion , which i n t u r n causes t h e
Since t h e v i s c o s i t y of g lyce r ine i s temperature
- 3 -
I n l e t Gas Flow Rate-Standard Cubic Feet Per Hour
t Table 1. Experimental Surface P r o f i l e s Obtained Through Use of t h e Five Foot Square Bubble Tank. D i s t i l l e d Water Nitrogen System.
Average Surface P r o f i l e Data, f e e t Number of Sur face Disturbances Analyz- ed t o Yield Average Surface P r o f i l e Data
'm 'r=O 'rx0.25 'r-0.50 'r=O. 75
12.36 0.0684 0.0583 0.0526 0.0436 0.0291 60
21.55 0.1012 0,0825 0.0753 0.0625 -0.0378 59
23.70 0.0994 0.0828 0.0722 0.0594 0.0374 60
- 4 -
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glycer ine-water mixture temperature t o vary, t h e v i s c o s i t y of t h e
mixture w a s measured several times during t h e course of a run and
averaged. I n every in s t ance where a v i s c o s i t y va lue i s quoted, e.g. ,
on curves of entrainment versus t i m e , i t r e p r e s e n t s an average value.
S ince only a l i m i t e d range of v i s c o s i t y va lues has been inves-
t i g a t e d t o d a t e , t h e r e s u l t s t o be presented are no t conclus ive ,
however, c e r t a i n t r ends are indica ted . It should be pointed out
t h a t t h e amount of t i m e requi red t o complete a run a t a given average
a i r mass flow rate has now doubled t h a t requi red f o r t he water tes t .
The geometr ica l conf igura t ions prev ious ly s tud ied us ing water
as t h e confined l i q u i d are being used f o r t h i s i n v e s t i g a t i o n so t h a t
geometr ica l i n f luences on t h e entrainment w i l l b e t h e same f o r both
series of tests.
is shown i n f i g u r e 12. Also, t h e same upstream-air s t a t i c p re s su res
used i n t h e water tests are being used i n t h e v a r i a b l e v i s c o s i t y t es t ,
however, f o r a given upstream a i r p re s su re t h e average mass f low rates
are d i f f e r e n t f o r t h e two series of tests; t h e m a s s f low rate f o r t h e
v a r i a b l e v i s c o s i t y tes t being s l i g h t l y higher . This r e s u l t s from t h e
changes made t o t h e en t ra ined- l iqu id carry-out system t o reclaim t h e
glycer ine-water mixture; t h e p re s su re loss now being a c t u a l l y less than
i n t h e water system.
The geometr ical conf igu ra t ion p resen t ly being t e s t e d
Flow C h a r a c t e r i s t i c s
For glycerine-water mixtures wi th v i s c o s i t i e s up t o approxi-
mately 50% g r e a t e r than that of water a t s tandard temperature ( v i s c o s i t y
approximately one c e n t i p o i s e ) , no apprec i ab le changes t o t h e l i q u i d f l o w
- 16 -
t 6
Glycerine-water mixture
4" Pyrex pipe, length variable reducer elbow
Figure 12. Entrainment Test Section
. c h a r a c t e r i s t i c s prev ious ly repor ted f o r water i n t h e h o r i z o n t a l p a r t
of t h e test s e c t i o n shown i n f i g u r e 1 2 could b e observed.
e n t zones of flow def ined i n Annual Report #2 q u a l i t a t i v e l y desc r ibe
t h e f low phenomena observed i n t h e p re sen t series of tests.
f o r a glycer ine-water mixture with a v i s c o s i t y of approximately f o u r
c e n t i p o i s e the wavelength and amplitude of t h e waves i n zone 3 were
cons iderably less than i n t h e water tests f o r approximately t h e same
average mass flow ra te of air . Other c h a r a c t e r i s t i c s of t h e f low were
i d e n t i c a l , wi th an apparent i nc rease i n m i s t formation a t the downstream
end of zone 3 where t h e waves impinge on t h e 90' elbow j o i n i n g t h e
h o r i z o n t a l p ipe t o t h e v e r t i c a l pipe.
a decrease i n t h e s u r f a c e tension.) The major means by which t h e
glycer ine-water mixture i s t ranspor ted from t h e test s e c t i o n i s by
t h i s wave impingement which sp lashes l i q u i d up i n t o t h e ver t ica l p ipe
forming both a f i n e m i s t and a t h i n f i l m which is c a r r i e d by t h e a i r
up t h e ver t ica l pipe.
p ipe i n d i c a t e s t h a t t h e w e t a b i l i t y of t h e glycer ine-water mixture i s
g r e a t e r than t h a t of t h e water; t h e f i l m covers a l a r g e r percentage
of t he s u r f a c e of t h e v e r t i c a l p ipe than f o r water a t small average
mass flow rates of a i r .
The d i f f e r -
However,
(This is l i k e l y t h e r e s u l t of
Visua l observa t ion of t h e flow i n the ver t ica l
The flow i n t h e vertical p i p e f o r t h e glycerine-water mixtures
i n v e s t i g a t e d t o d a t e , v i s c o s i t i e s of from l c p t o 4Cp,l is s imi l a r t o
t h a t descr ibed and shown i n f i g u r e 11 of Annual Report 82.
mix ture wi th a v i s c o s i t y of approximately 4 cp t h e r e w a s an apparent
i n c r e a s e i n t h e amount of m i s t being c a r r i e d up t h e v e r t i c a l pipe.
The m i s t was not formed by l i q u i d i n t h e f i l m f a l l i n g back i n t o t h e
For a
- 18 -
h o r i z o n t a l p ipe , as i n t h e water tests, b u t by t h e impingement of
waves on t h e downstream 90' elbow.
p e r i o d i c a l l y which r e s u l t e d i n an i n c r e a s e i n m i s t formation.
Some f r o t h i n g was observed
Entrainment Rates
Figures 13 and 14 are p l o t s of entrainment E ve r sus t i m e t f o r
entrapped l i q u i d q u a n t i t i e s of 1 /4 and 1 / 2 of t h e t o t a l volume of t h e
h o r i z o n t a l p ipe of t h e test sec t ion ; t h e curves are f o r a given average
mass flow rate and l i q u i d v i scos i ty .
Appendix I.) It is obvious upon a quick in spec t ion of t h e s e p l o t s
t h a t nea r ly a l l of t h e curves a r e f o r a d i f f e r e n t va lue of t h e v i s c o s i t y .
This r e s u l t s from t h e sharp dependence of t h e v i s c o s i t y of g lyce r ine
upon temperature , and t h e f a c t t h a t t h e temperature of t h e g lycer ine-
water mixture varies during the course of a day ' s opera t ion .
above p o i n t s were d iscussed previously. The entrainment curves f o r
water are no t shown i n f i g u r e s 1 3 and 14 s i n c e t h e average a i r mass
f low rates d i f f e r by as much as 4 lbm/min from those f o r t he g lycer ine-
water test f o r t he same upstream air s t a t i c pressure . The reason f o r
t h i s flow rate d i f f e r e n c e has been explained.
(The d a t a are presented i n
The
For t h e 1 / 2 f i l l e d case, f i g u r e 13, the d a t a i s l i m i t e d t o t h e
v i s c o s i t y range 1.19 cp t o 1.364 cp wi th only one va lue of t h e v i s c o s i t y
f o r each of t h e average air mass flow rates of 12.55 lbm/min and 9.96
lbm/min. For a i r mass flow r a t e s of 6.66 lbm/min and 4.11 lbm/min two
v i s c o s i t y curves are shown i n f i g u r e 13 f o r each flow rate ( t h e visco-
s i t ies d i f f e r by approximately 9%).
v i s c o s i t y caused a r educ t ion i n t h e entrainment a t a l l t i m e s .
I n each case a n inc rease i n t h e
A t t h e
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- 21 -
lower mass flow rate t h e reduct ion i n entrainment w a s t h e g r e a t e s t ; as
much as 57% at t-10 min., however, as t i n c r e a s e s t h e t o t a l reduct ion i s
approximately 23%.
have n e g l i g i b l e e f f e c t upon entrainment a t t h e h ighe r ( g r e a t e r than 6.66
lbm/min) flow rates.
reduct ions i n entrainment found as the v i s c o s i t y of t h e l i q u i d w a s in-
c reased may b e a t t r i b u t e d p r imar i ly t o t h e increased f r i c t i o n a l l o s s of
t he f i l m i n t h e v e r t i c a l p ipe ; of secondary importance i s the inc rease
i n m i s t formation and removal of l i q u i d as f i n e d r o p l e t s en t r a ined i n
t h e a i r , t h e sum of t h e two "entrainment-reducing" e f f e c t s , increased
f r i c t i o n a l l o s s and s p e c i f i c g r a v i t y , outweighs t h i s "entrainment-
increas ing" e f f e c t .
It appears t h a t s m a l l changes t o t h e v i s c o s i t y w i l l
Addi t ional d a t a i n t h i s area i s requi red . The
For t h e 1 / 4 - f i l l e d case, f i g u r e 14, s e v e r a l v i s c o s i t y curves are
shown f o r each average air mass flow rate.
1 7 lbm/min t o 22 lbm/min, i nc reases i n v i s c o s i t y of around 360% did n o t
m a t e r i a l l y a f f e c t t h e entrainment , though t h e r e w a s some reduct ion. A t
t h e s e hggher flow rates a major i ty of t h e l i q u i d is removed i n i t i a l l y
i n l a r g e s lugs .
t e s t e d d id not exceed 1.13 and s i n c e v i s c o s i t y does no t m a t e r i a l l y e f f e c t
s l u g flow ( t h e g r a v i t y f o r c e being predominate i n t h e p a r t i c u l a r geometry
of t h i s research) t h e r e should be l i t t l e e f f e c t upon t h e entrainment a t
t h e s e flow rates as t h e v i s c o s i t y is increased t o approximately 4 cp wi th
a corresponding s p e c i f i c g rav i ty of 1.13.
t o 7.5 lbm/min., t h e entrainment curves f o r a v i s c o s i t y of approximately
4 cp are cons iderably below those f o r a v i s c o s i t y of 1.39 cp. Since t h e
For t h e h igher a i r flow rates,
S ince t h e s p e c i f i c g r a v i t y of t h e glycerine-water mixtures
For lower flow rates, 10.8
- 22 -
. removal of t he l i q u i d from the test s e c t i o n a t these f low rates is
predominately by the flowing f i lm, v i s c o s i t y changes have more e f f e c t
on t h e entrainment.
CURRENT PROBLEMS
Surface P r o f i l e
Now t h a t t h e l a r g e r tank is i n use , t h e previous problems i n
ob ta in ing unobscured motion p i c t u r e record ings of t h e s u r f a c e d i s t u r -
bances have been e l imina ted and t h e r e are no problems delaying t h e
work a t t h i s t i m e .
Entrainment
There are no problems delaying t h e work on t h e entrainment
phase of t h e research a t t h i s t i m e .
PLANS FOR NEXT QUARTER
Surface P r o f i l e
The c o r r e l a t i o n s given i n F igures 1 through 7 w i l l be extended
i n t o t h e h igher i n l e t gas flow rate regime through a n a l y s i s of motion
p i c t u r e record ings made using t h e new l a r g e bubble tank.
Entrainment
The v a r i a b l e v i s c o s i t y tests w i l l be cont inued, t o be terminated
wi th tests f o r pure g lycer ine .
- 23 -
.
APPENDIX I
ENTRAINMENT DATA
Table 11. Entrainment Versus T i m e f o r Test S e c t i o n Shown i n Figure 12 (1/4 - F i l l e d ) f o r Various A i r Flow Rates and Liquid V i s c o s i t i e s
T i m e Min .
0- 5 0-10 0-20 - 0-30
0- 10
0-3 0-5 0-10 0-15 0-20 0-25
0-3 0- 5 0-10 0-15 0-20
0-3 0- 5 0-10
0- 2 0-3 0-5 0-10
0-2 0-3 0- 5
Ups t ream Average Mass Average Liquid Entrainment
Inches Hg Dry A i r Cent ipoise A i r P r e s s u r e Flow Bate of Viscos i ty
lbm/min
3.2 7.575 1.39 0.1485 7.555 0.193 7.530 0.222 7.530 0.232
3.2 7.250 3.67 0.0125
6.4 10.890 1.39 0.582 10.905 0.619
0.670 10.815 10.770 0.70 10.940 0.729
0.740 10.840
6.4 11.04 2.79 0.406 11.00 0.478 11.035 0.533 11.035 0.557 10.97 0.588
12.8 16.275 1.44 0.916 16.320 0.946 16.205 0.947
12.8 16.203 4.12 0.904 16.17 0.91 16.23 0.925 16.22 0.931
19.2 21.235 1.387 0.986 21.380 0.994 21.260
- 25 -
0- 2 0-3 0-5
19.2 21.28 3.65 0.988 21.32 0.996
0.996 21.265
II B b l e 111. Entrainment Versus T i m e for Test Section Shown i n Figure 12 (1/2-Filled) for Various A i r Flow Rates and Liquid Viscos i t ies
Time Min
0- 5 0-10 0-20 0-30
0-5 0-10 0-20 0-30 0-40
.
Upstream Average Mass Air Pressure Flow Rate of
Inches Hg Dry A i r lbm/min
1.4 4.185 4.055 4.020 4.040
1 .4 4.235 4.195 4.145 4.160 4.040
1 . 0- 5 0-10 0-20 0-30
0-5 0-10 0-20 0-30
0- 3 0-5 0-10 0-20
0-3 0- 5 0-10
2.8 6.600 6.515 6.615 6.705
2.8 6.700 6.765 6.715 6.635
5.6 9.910 9.985
10.045 9.920
5.6 10.020 9.990
10.055
0-2 0- 5 0-10
8.4 12.555 12.485 12.605
Average Liquid Viscosity Centiposie
1.249
1.364
1.145
1.252
1.269
~ ~~
1.190
Entrainment
0.126 0.185 0.236 0.252
0.049 0.082 0.132 0.168 0.195
0.433 0.457 0.484 0.496
0.397 0.428 0.457 0.480
0.734 0.745 0.778 0.792
0.734 0.737 0.755
0.871 0.895 0.907
- 2G -