Scholars' Mine
Masters Theses
Student Research & Creative Works
1966
Nucleate boiling heat transfer to liquid nitrogen at
atmospheric pressure
Satish R. Parikh
Follow this and additional works at: http://scholarsmine.mst.edu/masters_theses
Part of the Chemical Engineering Commons
Department: Chemical and Biochemical Engineering
Recommended Citation
Parikh, Satish R., "Nucleate boiling heat transfer to liquid nitrogen at atmospheric pressure" (1966). Masters Theses. 5741.
http://scholarsmine.mst.edu/masters_theses/5741
This Thesis - Open Access is brought to you for free and open access by Scholars' Mine. It has been accepted for inclusion in Masters Theses by an
authorized administrator of Scholars' Mine. 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].
NUCLEATE BOILING HEAT TRANSFER
TO LIQUID NITROGEN
AT ATMOSPHERIC PRESSURE
BY
SATISH R. PARIKH
A
THESIS
submitted to the faculty of
THE UNIVERSITY OF MISSOURI AT ROLLA
in partial fulfillment of the requirements for the
Degree of
MASTER OF SCIENCE IN CHEMICAL ENGINEERING
Rolla, Missouri
1966
Approved by
~~
;/,?~jlf?~
'V~-:_:
/r
l~~
~ .
(Advisor)~<
/
ii
ACKNOWLEDGEMENTS
The author wishes to express his appreciation to Dr. Efton L.
Park, Jr. , for his suggestion of this investigation.
His help, guid-
ance and encouragement are sincerely appreciated.
The author also expresses his thanks to Mr. Virgil Flanigan,
for his help and timely valuable
thanks is extended to
element asseml::>ly.
~r.
s~ggestions.
A further word of
Lee Andersoq for helping make the heating
~··
The author gratefully acknowledges the facilities and space
provided by the Mechanical Engineering Department, the laboratory
assistantship from the Department of Chemistry, and the financial
assistance received from the National Science Foundation.
iii
ABSTRACT
The object of this investigation was to study the effect of microroughness, a thin layer of oil, and infra-red radiations on the cylindrical heat transfer surface of copper, in liquid nitrogen and at
atmospheric pressure during nucleate boiling.
An attempt was made
to find any possible effect of orientation of the heat transfer element
on nucleate boiling.
A number of different runs were taken with
different degrees of roughness, and different orientation positions.
Nucleate boiling has been found to be nearly independent of the heat
transfer surface roughness ·and of orientation while strongly dependent on the chemical nature of the surface.
Extremely high tempera-
ture differences were obtained in the nucleate boiling region by
application of a thin layer of oil to the heat transfer surface.
Tem-
perature gradients in both the axial direction and the radial direction
were found for the sur'face of the heat transfer element.
iv
TABLE OF CONTENTS
Page
TITLE PAGE
1
ABSTRACT.
11
ACKNOWLEDGEMENTS
iii
TABLE OF CONTENTS
iv
LIST OF ILLUSTRATIONS
vi
LIST OF TABLES .
vii
NOMENCLATURE.
viii
I.
INTRODUCTION
II.
LITERATURE REVIEW
1
...
Cavity Geometry and its Effect.
Mechanisms .
III.
. . . .
.
5
5
.
8
Correlations .
10
Physical Interpretation of Critical ~ T
16
Thermodynamic View-point .
17
Kinetic View-point
.
18
. ...
22
Purpose of Investigation.
22
EXPERIMENTAL .
. ..
Experimental Equipment
22
25
Experimental Procedure
IV.
RESULTS AND DISCUSSION
v.
DISCUSSION OF ERRORS
VI.
CONCLUSIONS .
.
.
.
.
. .. . . . . . . .
• .
• .
.
.
.
.
.
• • .
.
27
41
.
• • .
.
.
.
45
v
VII.
APPENDICES .
.....................
44
Appendix A - Experimental Data
45
Appendix B - Sample Calculation
72
Appendix C - Computer Program for Calculation
of Heat Flux and Heat Transfer
Coefficient
73
Appendix D - Calibration of Thermocouples
74
Appendix E - Discussion of the Effect of End
Losses from the Heat Transfer
Element . . . . . . . . . . . . .
77
Appendix F - Schematic Drawing of Electrical
Circuit for Experimental Work.
80a
VIII.
BIBLIOGRAPHY.
81
IX.
VITA . . . . . . .
85
Vl
LIST OF ILLUSTRATIONS
Figure
Page
1
A typical boiling heat transfer curve
2
Graph of equation of state, such as Van der
Waal' s equation, showing the metastable
conditions
19
Effect of superheat on the rate of formation of
nuclei
20
4
Heat transfer element (Sectional view)
23
5
Drawing of Heater (Outer Surface only), showing the
position of six thermocouples
28
AT versus heat flux, nitrogen nucleate boiling,
comparison of thermocouple 1, thermocouple 3,
thermocouple 6 with thermocouple 5
29
AT versus heat flux, nitrogen nucleate boiling,
comparision of thermocouple 2 with thermocouple 4
31
AT versus heat flux, nitrogen nucleate boiling,
comparison of horizontal, 45° and vertical
positions
33
AT versus heat flux, nitrogen nucleate boiling,
comparison after surface treatment with HCl
35
AT versus heat flux, nitrogen nucleate boiling,
comparison after different surface roughness
36
AT versus heat flux, nitrogen nucleate boiling,
comparision after surface treatment with HCl,
oil and crocus paper, and infra-red radiations
38
AT versus heat flux, nitrogen nucleate boiling,
varying from pressure 14. 5 psi to 442 psi
40
13
Calibration of thermocouples
75
14
Schematic Drawing of Electrical Circuit for
Experimental Work
80a
3
6
7
8
9
10
11
12
2
vii
LIST OF TABLES
Table
A-I
Page
Nucleate boiling data for nitrogen, heat transfer
surface, horizontal position
46
Nucleate boiling data for nitrogen, heat transfer
surface, at 45 position
53
Nucleate boiling data for nitrogen, heat transfer
surface, vertical position
55
Nucleate boiling data for nitrogen, heat transfer
surface, treatment with HCl
57
Nucleate boiling data for nitrogen, heat transfer
surface, treatment with HCl followed by Ethyl
Alcohol
60
Nucleate boiling data for nitrogen, heat transfer
surface, various treatment by crocus paper
and sand paper
62
Nucleate boiling data for nitrogen, heat transfer
surface, treatment by infra-red radiations
65
Nucleate boiling data for nitrogen, heat transfer
surface, treatment by cutting oil
66
Nucleate boiling data for nitrogen, heat transfer
surface, treatment by cutting oil and Fe 2 o 3
68
A-X
Film boiling data for nitrogen
69
A-XI
Comparison of heat flux and burnout temperatures
for different conditions
71
D-I
Thermocouple calibration
76
E-I
T emperature difference and percentage heat
loss for thermocouple 1 and thermocouple 3
78
Temperature difference and percentage heat loss
for thermocouple 2 and thermocouple 4
79
Temperature difference and perc entage heat loss
for thermocouple 5 and thermocouple 6
80
A-II
A-III
A-IV
A-V
A-VI
A-VII
A- VIII
A-IX
E-ll
E-III
°
Vlll
NOMENCLATURE
A
=
Area, ft. 2
a
=
Thermal diffusivity, lb. /hr. ft.
c
:::
Specific heat, Btu/lb. °F.
D
=
Diameter, ft.
E
:::
Potential, volt.
F
:::
Free energy, ft. -lb.
g
:::
Acceleration due to gravity, ft. / sec.2
h, H
=
Heat transfer coefficient, Btu/hr. £t.2 OF.
h, L
=
Latent heat of vaporization, Btu/lb.
I
=
Current, amperes
J
:::
Mechanical equivalent of heat
k
=
Boltzman constant, energy/ (deg. temp. } (molecules}
k
=
Thermal conductivity, Btu/hr. ft.2 °F/£t.
M
:::
Molecular weight
N
:::
Total no. of molecules in the system
n
:::
Number of nucleation sites
p
:::
Pressure, atm. or psia
p
=
Parachore
.6.P
:::
Pressure difference, atm. or psia
q, Q
=
Rate of heat transfer, Btu/hr.
R
:::
Universal gas constant
T
:::
Temperature
0
F or
0
R
ix
AT
=
Temperature difference, {T
v
=
Volume of entire systern, cu. ft.
v
:::
Volume of a bubble, cu. ft.
V
=
Velocity, ft.
f
- T 1. .d)
sur ace
1qu1
I sec.
Greek Symbols:
e
=
Temperature difference oc
=
Constants
X
=
Distance, em.
T
:::
Time, sec.
ex
=
Thermal diffusi vity, sq. ft. lhr.
p
=
Density, lb.
0"
=
Surface tension, lb.rf ft.
1-'-
=
Viscosity, lb.
A.
=
Latent heat of vaporization, Btu/lb. mass.
ex,
~
I cu. ft.
I ft.-hr.
Subscripts:
b
refers to bubble
c
refers to critical point
1, L, f
refers to liquid
v,
v, g
refers to vapor
r
refers to reduced property
s
refers to saturated condition
TC
refers to thermocouple
X
Dimensionless Expressions:
Nu
=
Nusselt Number, hD
k
Re
=
Reynolds Number,
DVp
f.l.
I.
INTRODUCTION
Heat transfer to boiling liquids is a form of heat transfer with
a change of phase.
It has increased in importance with the develop-
ment of the nuclear reactor, the rocket nozzle, spacecraft and
cryogenic equipment.
Nucleate boiling is a method of increasing
heat transfer rates at modest temperature differences.
transfer flux
Heat
in modern boilers are 20, 000 to 90, 000 Btu/hr.
£t.Z
but, in nuclear reactors, rocket nozzles and spacecraft, they may
be of the order of 10 6 to 107 Btu/hr. ft. 2
Attempts to provide low
cost conversion of sea water using multi-effect evaporators have
renewed interest in transferring the maximum amount of heat under
the influence of the available overall temperature drop.
Four distinct regions have been established in boiling heat
transfer (29, 30, 34) according to the temperature difference across
the film.
These are defined respectively as the convective, nucleate,
metastable, and stable film boiling regions as shown in Figure 1.
As the wall temperature rises above the saturation temperature, convective currents circulate superheated liquid, and vapor is
produced by evaporation at the free surface of the liquid (Region I).
With increase in surface temperature, formation of vapor
bubbles take place.
These bubbles rise from active sites on the
metal surface and condense before reaching the free surface of the
liquid (Region II).
---,.-------·----·-·
CorJ VEC TlV E
I
NUCLEATE
]I
t-1 L f"f\.·,
]I
-r A eu::
"f\Lfl\
y
I\f
"Sii
A
<
-:--...
0
f
..
""'
p
,.,.~
...:t
~
E-i
~
:r::
0
B
3
I
'
'I
I
I
LOG TEMPERATURE DIFFERENCE, AT
Figure 1: A Typical Boiling Heat Transfer Curve (30)
N
3
More and larger bubbles form with nucleate boiling and this
is the region of greatest interest (Region III).
Beyond the peak of the curve, an unstable film of vapor forms
on the heat transfer surface.
This vapor film is not stable, and it
collapses and reforms rapidly.
The presence of this film provides
additional resistance to heat transfer, and reduces the heat transfer
rate (Region IV).
Next, the vapor film becomes stable in the sense that it does
not collapse and reform repeatedly, but the shape of the outer film
surface is varying continuously.
Here the heater surface is blanketed
with an insulating film of vapor, and the heat transfer rate is quite
low {Region V).
Finally, at a large value of temperature difference, the influence of radiation becomes pronounced.
The vapor film is very stable,
and the bubble formation is controlled by factors operating at the
outer surface of the film, so that the heater surface has little effect
{Region VI).
Point A in Figure 1 is known as the critical heat flux or burnout
point and point B is known as Liedenfrost point.
If a cold liquid {below the boiling point), is caused to flow past
a hot surface, subcooled boiling results.
Because the boiling exists
on the solid only, this is often called surface boiling.
collapse in the body of cold bulk liquid.
The bubbles
The combination of forced
4
flow plus the natural agitation caused by bubble growth and collapse
produces very high heat transfer coefficients.
Heat fluxes of nearly
10 7 Btu/hr. ft.2 have been reported for subcooled liquid boiling (38).
If a liquid is heated by infra-red radiation, by passage of an
electric current through the liquid; by chemical reactions occurring
between dissolved components in the liquid, or by atomic reactions,
volume heated boiling can occur.
Bubbles grow in the bulk liquid and
this can be considered as one type of nucleate boiling (38).
5
II.
LITERATURE REVIEW
Much concentration has been devoted to boiling heat transfer
and a number of papers have been published, especially in the U. S. A. ,
Russia and Japan.
Current work deals with a number of articles con-
cerned with nuclei or sites on which bubbles form in the nucleate
boiling region.
Gartner and Westwater ( 14) explained that at low heat fluxes
the number of active sites do not increase smoothly but rather by
steps.
From their experiments they reported the highest count of
the number of sites to be 1130/ sq. in. with the upper limit unknown.
At the same time, a linear relationship between the number of active
sites and heat flux as suggested by Jacob (23) was disproved.
Cavity Geometry and its Effect:
Corty and Foust (7) experi-
mentally showed that the size and shape distributions of the microroughness in the heat transfer surface and to a lesser extent the
contact angles of the bubbles in the nucleus cavities are significant
variables in nucleate boiling.
Their observations showed that during
nucleate boiling the distribution of active centers and the heat transfer
coefficients, varied with the immediate past history of boiling.
Corty and Foust suggested that there exists cavities in a metallic surface and that in these cavities vapor is trapped after the earlier
bubbles have broken loose.
The trapped vapor then acts as the
nucleus for the next bubble from the same spot.
They found that the
6
position and the slope of the boiling curve vary with roughness.
They
concluded that the AT in nucleate boiling decreases with increasing
roughness, but the maximum AT that can be reached by increasing
the power, in the absence of bubbles increases with increasing
roughness.
Griffith and Wallis ( 16) suggested that cavity geometry is important in two ways.
The mouth diameter determines the superheat
needed to initiate boiling and its shape determines its stability once
boiling has begun.
Contact angle is shown to be important in bubble
nucleation primarily through its effect on cavity stability.
Forster and Zuber (11) derived an analytical expression for
bubble radii and growth rates which can be applied in the analysis of
surface boiling at high heat transfer rates.
Madejski (27) assumed that the heat flux in boiling heat transfer
consists of three components: the first due to the flow of columns of
bubbles; the second due to the molecular heat conduction in the liquid;
and the third is due to the eddy convection.
from data on the bubbling process.
The latter was estimated
A relationship was developed
between the local bubble diameter and the temperature difference. It
was found that
(Nu) (\.)
(Re) 213
(1)
for sufficiently great Nusselt moduli under the assumption that the
7
bubble population is inversely proportional to the radius of a
nucleus.
Strenge, Orell and Westwater {36) reported quantitatively,
relations for bubble vibrations, irregularities in nucleation, and
statistical vibration in growth rates.
Roll and Myers (35) showed the effect of surface tension and
obtained the following relations.
eb
and
where
Td
=
=
1.613
{2)
xb
1
a
2
9
( Xb w
)
2{9w -9b)
{3)
eb = Bubble temperature minus liquid saturation temperature,
oc.
13 =
Constant.
xb = Distance from boiling surface to top of bubble, Cm.
Td = Delay time, Sec.
a =
ew
=
Thermal diffusivity, sq. em. /sec.
(T surface
-
T saturated), oc.
They explained how surface tension changes are reflected by
changes in delay time, growth time and volume.
Clark, Strenge and Westwater (5) using a high speed photography
technique showed that pits with diameters between 0. 0003 and 0. 003
inches are very active nucleation sites.
Some scratches, a metal-
8
plastic (metal and insulating material, in their work it was aluminum
and Duco-cement} interface and a mobile speck of unidentified material were also found to be active sites.
In no case did bubbles form at
grain boundaries and no difference in activity could be found for the
various crystal faces of Zinc, an anisotropic material.
Githinji and Sabersky (15} performed experimental work with
the same heating surface which was tested in various positions with
respect to the gravitational field without altering any of the other test
conditions.
Their results confirmed the fact that the orientation of
heating surface with respect to the direction of the gravitational field
is of major importance in nucleate boiling heat transfer.
Young and Hummel (39} improved nucleate boiling heat transfer
for the same conditions by addition of stable sites by application of
tetraflouoro-ethylene resin which is commercially available in the
form that will adhere to metals, (Du-pont teflon TFE-fluorocarbon
resin one coat green enamel}.
Mechanisms: An exact mechanism has not been established for
the nucleate boiling heat transfer; however, different theories are
reported in the literature.
Mechanism 1:
Microconvection in Boundary Layer ( 10}.
As bubbles grow and collapse, a large convective velocity is
developed which causes high rates of heat transfer to be developed in
the superheated sublayer of a liquid.
Experiments show that for the
9
same superheat ( Twall - T saturated), the heat flux in nucleate boiling
remains essentially unaffected while the subcooling may increase by
. .d) may increase
a factor of ten, and the temperature (T wa 11 - T 11qu1
by a factor of three.
This was not explained by this mechanism.
Mechanism 2:
Latent Heat Transport by Bubbles (4).
Jacob and Fritz postulated that as a bubble grows it absorbs
latent heat of vaporization which is returned to the liquid bulk when
the bubble collapses.
Mechanism 3:
Vapor -liquid Exchange Action.
This theory postulates that bubbles act as a pump, lifting superheated
liquid into the bulk as they grow and return saturated (or subcooled)
liquid to the bare surface of the heating element as they detach or
collapse.
Mechanism 4:
Mass Transfer through Bubbles.
Moore and Mesler (31) observed in their experiment that the
surface temperature during nucleate boiling of water at atmospheric
pressure varies with time.
An interesting characteristic of the var-
iation is that occasionally the temperature suddenly drops 20° to
30° F.
in about 2 microseconds.
This drop indicated rapid removal
of heat from the surface during this short interval.
This suggested
the possibility of a fourth type of mechanism in which as a bubble
grows on the surface, it exposes the heating surface wet with a microlayer of liquid to the interior of the bubble.
This microlayer of liquid
10
rapidly vaporizes removing heat rapidly from the surface until it is
completely vaporized.
This sequence of events explained the rapid
removal of heat occurring during the short period of time when the
surface temperature dropped quickly.
Presently, Mr. Hospeti (20) is studying this phenomena in
detail at the University of Kansas, Lawrence, Kansas.
Though these different mechanisms have been postulated, it is
not definite yet which mechanism is valid, or if any of them are valid.
It is possible that a number of different mechanisms might be taking
place simultaneously (13).
Gartner ( 13) carried on a detailed photographic study of nucleate
pool boiling on a horizontal surface.
He concluded that there are four
distinct heat transfer regions in nucleate boiling, depending upon the
mode of vapor generation.
The vapor structures on the surface pro-
gressed through a sequence of discrete mushrooms and finally vapor
patches, as the surface temperature was increased.
These individual
vapor structures or combinations of them, determine the mechanism
of heat transfer in the four nucleate boiling regions.
Gartner con-
cluded that any heat transfer model or design equation which is based
on the dynamics of an individual bubble, or any other single mechanism, must be in serious error.
Correlations:
Cinchelli and Bonilla (4} related empirically
their experimental values for a number of different organic liquids
11
by the following equation.
(Q/ A)max.
Pr
=
ex f {Pr)
{4)
Pr = Reduced pressure.
where
ex = 1 for clean surfaces
ex =
l. 15 for dirty surfaces
Forster and Grief's ( 1 O) work yielded the correlation
a =
A
1.
(p~~ 5/8 f:cf3AP2
z x 1o- 3
(5)
where
a
=
Thermal diffusivity, lb. /hr. ft.
p
=
Density, lb.
c =
I cu. ft.
Specific heat at constant pressure, Btu/lb. deg. F.
= Saturated temperature,
Ts
=
T
J
=
Mechanical equivalent of heat.
L
=
Latent heat of vaporization, Btu/lb.
0"
=
Surface tension, lb.f/ft.
(J.
=
Viscosity, lb. /hr. ft.
ap
sat.
oF.
= Pressure difference corresponding to
superheat T,
lb. I ft. 2
K
=
Thermal conductivity, Btu/hr. ft.2 °F I ft.
But this equation was found to be valid only for the following
liquids under restricted physical conditions.
12
water - for pressure from 1 to 50 atmospheres.
n Butyl Alcohol - for 50 psia.
Anilin - for 35 psia.
Mercury - for 1 and 3 atmospheres.
Levy (24} postulated a generalized equation to describe surface
boiling of liquid.
His expression which attempts to correlate all fluids
independently of pressure and heating surface conditions is:
Q
A
where KL
=
(6}
Thermal conductivity of saturated liquid in
Btu/hr. ft. 2 °F/ft.
CL
= Specific
PL
= Density of liquid,
lb. /ft.3
Py
= Density of vapor,
lb. /ft.3
Ts
= Saturation temperature,
()
hfg
heat of fluid, Btu/lb. oF.
OR
= Surface tension, lb.f/ft.
= Constant (needs experimentation to
=
obtain}.
Latent heat of evaporation, Btu/lb.
The above expression was obtained from a simplified model of
heat transfer to the bubbles close to the heated surface.
The coeffi-
cient BL, determined empirically, was found to be a function of product Pyhfg·
The derived equation was obtained for the pool boiling
13
heat transfer and nucleate boiling heat transfer of subcooled and
vapor containing liquid.
Zuber (40) obtained the following equation for Qmax·
.ey o-g (pf e - p g}
~ 1 +"~
(7}
Pf
where, hfg
=
Enthalpy change from saturated liquid to saturated
vapor state, Btu/hr.
p
=
Density, lb.
g
=
Saturated vapor state.
f
=
=
Saturated liquid state.
o-
I cu. ft.
Surface tension between liquid and its vapor, lb. f
/ft.
The correlation obtained by Lienhard and Schrock (25) using
the Clausius-Clapeyron equation and law of corresponding states is:
(Qmax)r•
=
where,
where,
A
Qmin
(Qmin)r'
A.
Qmax
A
= trg
p
p
c M
=
f3 (Pr, Geometry)
(8)
=
f4 (Pr, Geometry)
(9)
(8 Mpc)
3/4
( 1 0)
3 R Tc
P is a parachor defined as
p
=
M
( 11)
14
P was predicted on the basis of molecular structure.
Each
atom, each chemical bond, and each special feature of the molecule 1 s
form contributes a certain fixed portion to the molecules parachore.
M
= Molecular weight.
R
=
Universal gas constant.
T
=
Absolute temperature.
g
=
Acceleration due to gravity.
p
=
Pressure.
subscript c refers to property at thermodynamic critical point.
Chang and Snyder {3) related peak heat flux and its corresponding temperature difference using a model whose mechanism is agitation
and latent heat transport.
Q
max
where,
= (1/4- 1/2) 4
X
10- 4
o-(A.p
kl
=
0.8
Thermal conductivity of liquid, Btu/hr. ft.2 °F /ft.
eo = Superheat
~p
v
)
0
F.
2
= Pressure difference corresponding to superheat, lb. I ft.
A.
=
Latent heat of vaporization, Btu/lb. mass.
o-
=
Surface tension, lbf/ft.
Pv
=
Density of vapor, lb. /£t.3
PL
= Density of liquid,
lb. I ft.
3
15
cp
=
Ts
= Temperature of saturated liquid, °F.
Specific heat, Btu/lb. °F.
T. Hara ( 18) calculated the heat transfer due to the liquid motion
near a nucleation site.
The heat flux thus calculated is equal to that
transferred from the heating surface to the liquid by conduction plus
the latent heat carried away by the bubbles per unit time.
For these
heat transfer rates the following theoretical formula was obtained.
~e
=
o.
114
n
-1/4
q
2/3
(13)
where ~8 is a temperature difference between the temperature
of the heating surface and the saturation temperature.
n is the num-
ber of nucleation sites and q is the average heat flux.
Hambuger ( 17) assumed (a) rising bubbles carry with them thin
boundary layers of superheated liquid, broken away at their departure
from the boundary layer of the heating surface (b) the disturbance
caused within the bulk by the bubbles are the same as if the bubbles
were solid bodies of the same shape and size.
Using the theory of
virtual masses and the above assumptions, a relation for the growth
rate and rise velocity of an individual vapor bubble is:
1/4
( 14)
where,
v0
= Rising velocity of bubble, ft. I sec.
o = Departure condition.
16
9
=
Contact angle in sexagessimal degrees.
cr
=
Surface tension coefficient, lb.£
g
=
Acceleration of gravity, ft./sec.
p
=
Density, lb.
L
=
Liquid.
v
=
Vapor.
I cu.
/ft.
2
ft.
A new procedure for correlating the maximum heat flux in the
nucleate boiling region has been developed by Cobb and Park (2).
This correlation is restricted to liquids which follow the theory of
corresponding states.
This proposed correlation can provide a
method of comparing maximum heat fluxes taken under different
experimental conditions.
This correlation can also be used to pre-
dict high pressure heat fluxes from atmospheric data.
Physical Interpretation of Critical .6.T (38):
If the critical .6.T
1s exceeded, three possible events can occur, the heat flux will remain constant, transition boiling may occur, with an accompaning
sharp decrease in the heat flux or the heat source may melt and burn
out.
Which of these events occurs depends on the source of heat and
the material of construction.
With respect to sound, nucleate boiling is the most quiet and
the film boiling is the noisiest of the three types of boiling studied
( 38).
17
As AT increases the number of bubbles increases up to a
certain limit, then they merge into continuous vapor film.
Thermodynamic view point: A conventional P-V -T diagram
(Fig. 2) for a single pure substance is shown.
AB represents a
typical isotherm for the liquid state and FG is an isotherm for the
vapor at the same temperature.
Hence at pressure PB liquid at
temperature T 2 and vapor at temperature T 2 would be in equilibrium,
or T 2 is the boiling point at PB and PB is the vapor pressure of liquid
at
Tz.
I£ a subcooled liquid at point A is expanded isothermally, it will
I£ the liquid is of high purity and no contamination is
boil at point B.
present, it proceeds to C.
Such a liquid is then under tension.
the liquid finally breaks a cavity appears.
Experimental results by
Briggs ( 1) shows BC is an attainable physical condition.
line FE is real.
is unstable.
When
Similarly
The portion CDE is completely unattainable, as it
Van der Waal' s equation is described by ABCDEFG.
BC and EF are called metastable isotherms.
It has been proved (Hirehfelder and co-workers) (31), that liquid
in tension such as that at temperature T 2 located on line BC is unstable
to macroscopic fluctuations, but stable to small fluctuations.
Portion
EF represents super saturated vapor which also is stable to tiny
fluctuations.
The line CDE corresponds to liquid or vapor which is
thermodynamically unstable to density fluctuations of any magnitude
18
whatever.
This means that states corresponding to CDE are 'com-
pletely unattainable'.
If a cold liquid is heated to boiling at constant pressure, the
path shown in Figure 2 will be from H to B.
liquid beyond B.
It is possible to heat the
From a standpoint of a correct equation state the
liquid could be superheated to point R, but not beyond this.
Thus a
maximum possible superheat (T3 - Tz) is predictable theoretically.
Kinetic view-point: Figure 3 represents the effect of superheat on the rate of formation of nuclei from the equation:
I
dno
d8
where
=
NkT
(15)
e
h
n~ = Number of nuclei.
8
=
Time in hrs.
N = Total number of molecules in a system.
k
=
Boltzman constant, energy/(deg. temp.) (molecule)
T
=
Temperature,
F'
=
Free energy of a liquid system, ft. -lb.
cr
=
Surface tension, liquid vapor interface, lb.f/ft.
0
R.
v = Volume of a bubble in cu. ft.
y
=
Volume of all bubbles covering entire free surface,
cu. ft.
1. critical point
From Rohs on ow ( 34=--_i
2. saturated liquid
3. saturated vapor
-r'l.
P-t
~
Cl.l
J...l
~
''\
C/l
C/l
Cl.l
J...l
P-t
I
'D
r...
u
I
•
H
'
fB•
'
\
I
I
'
I
'
,
,
,'
,
'1::,, ~'
'I
I
,
'{,
I
'
,'
ol' ,
R
tC '-------'
,-"
''
,------
"P
\
\
,~
E
,-...., ...
\
'S
.-
',
-· _,
'
......r
',)
K
•
,
'
T1
Molar Volume, V
Figure 2.
Graph of Equation of State, such as Vander Waal' s Equation,
Showing Metastable Conditions.
,_.
...0
20
CD
'D
...........
-0
I=!
'D
....,C)'
cD
~
I=!
0
......
....,
cD
(j)
I
~
r-i
u
~
cRITICAL.
:(
(Py - P L) Superheat
Figure 3.
Effect of Superheat on the Rate of
Formation of Nuclei {38}.
21
:::: Saturation pressure of a flat liquid surface at its
existing temperature, lb. I sq. ft.
Py :::: Pressure of vapor in a bubble, lb. I sq. ft.
Merte and Clark (30} performed an experiment for boiling liquid
nitrogen from a sphere at standard gravity and near zero gravity for
short residence times in the film transition and nucleate boiling
regions.
For a 1 inch diameter sphere of electrolytic, tough-pitch,
Copper in liquid nitrogen they obtained
(Q/ Abax. at a/ g~O
(Q/ A}max. at a/ g~ 1
=
0. 41
where a/ g :: force field acceleration ratio.
(16)
22
III.
EXPERIMENTAL
Purpose of Investigation:
The purpose of this investigation was
to study the effect of orientation, micro-roughness, a thin layer of
oil, and infra-red radiations on a cylindrical heat transfer surface
for nucleate boiling.
Experimental Equipment:
The experimental equipment design
and fabrication was based on Park's work {32).
The equipment consisted of a cylindrical copper heat transfer
element, a welder, a voltmeter, an ammeter, a variable resistor
and a potentiometer. (Electrical circuit diagram, Appendix F, p. 80a).
The heat transfer element was developed to insure sufficient
temperature difference between liquid nitrogen and the metallic sur. face for nucleate boiling and for film boiling.
The heat transfer
element had to withstand the thermal shock of going through the burnout point and film boiling temperature differences of 1000 °F.
The
heater design (Figure 4) consisted of a 0. 5 inch diameter inner core
of Lava with 18 grooves per inch cut to a depth of 0. 022 inches.
this core 22 gauge tungsten wire was wound in the grooves.
On
The ends
of the tungsten wire were fixed tightly by nuts screwed on to 1/8
inch diameter screws, which were screwed into the core.
screws acted as power leads for the tungsten wire.
The same
An inner hollow
cylinder of copper of a length of 3 inches with an inside diameter of
9 I 16 inch and an outside diameter of 0. 688 inch was slotted at six
7 6
1.
2.
3.
4.
5.
6.
7.
8.
8
Thermocouple leads
Outer copper cylinder
Inner copper cylinder
Tungsten windings
Inner core of lava
Transite end plate
Brass end plate
Cement
Figure 4.
J
--·-
Heat T.1:ansfer Fl.cmcnt {Sectional view)
----- --- ---------------
-----------
N
w
24
places.
The slots were located three on each side at 120° apart.
The length of the slots were 1 inch and 1. 5 inch from each end.
Six
22 gauge Iron-Constantan thermocouples were silver soldered in the
ends of the slots.
This cylinder with thermocouples in place was
then shrunk fit into an outer copper cylinder of 0. 6875 inch inside
diameter and 0. 8 inch outside diameter.
The wire wound core was
coated with WM T Bean type H cement to prevent direct contact of
the heating coil and the cylinder, and was cemented into the cylinder.
To minimize heat losses, end plates made of transite were cemented
to the ends using the same epoxy (WM T Bean type H cement) and
then brass plates were added as end plates to give support to the
transite end plates.
The heat transfer element was connected in series to the welder,
used as a power source.
The welder was rated at a maximum of 40
volts and 300 amperes.
Variable resistance was also connected in series to control
and to vary the power through the heating element.
With the applica-
tion of resistance the voltage could be varied between 0 and 40 volts.
Energy supplied to the heater element was measured by current
flow and voltage drop across the heater.
A Weston D. C. Ammeter
model 1 having a range 0 - 50 amperes and an accuracy of 0. 5
amperes was used.
The potantial drop was measured using a Weston
D. C. Voltmeter model 45 which had two scales, 0 - 30 volts and
0 - 300 volts.
Accuracy for the voltmeter was 1/4th of 1% of the
full scale that was used.
26
With a new welder, the burnout point was reached.
Amperage,
voltage and emf readings were noted for the power input until the
burnout point was reached.
Readings were noted only after the steady
state was reached and the reading for the first thermocouple was rechecked for every set of readings.
In nucleate boiling, hysterises effects (7) have been observed,
hence care was taken always to increase the power.
However, in
run 19 the circuit was broken before burnout and it was restarted at
the last set of readings.
It was noted that it took longer to reach steady state for high
AT's than at lower AT's.
A number of runs were taken with the
heater located at 45° and in the vertical position.
Film boiling data were noted for a few runs, but it was difficult
and time consuming to obtain due to its very unsteady nature.
Several sets of data were collected on a cylindrical copper
heat transfer surface.
The surface conditions were varied by coat-
ing the surface with a deposit of cutting oil>:e and by roughening the
surface with emery paper and crocus cloth>:o:e.
One set of data was
also collected when a mixture of oil and Ferrous Oxide had been rubbed
on the copper surface.
Sunnen Fast Cutting Honing Oil, Sunnen Product Company,
St. Louis.
Crocus Cloth, jewel, No. 45063, Abrasive Products, Inc.,
Massachusetts.
27
IV.
RESULTS AND DISCUSSION
Most nucleate boiling data is represented as a plot of the
logarithm of temperature difference versus the logarithm of heat
flux which tends to mask the scatter of the data.
Park (32) suggested
that the data could be better represented as plots of the temperature
difference versus the heat flux.
The data has been plotted as .dT
versus heat flux in this investigation.
There were six thermocouples imbedded in the heat transfer
element which allowed the determination of any temperature gradients
in the radial or axial direction.
The thermocouples were located as
shown in Figure 5.
Figure 6 shows a comparison of the thermocouples near the
top of the heat transfer element ( 1, 5, 3, 6 ).
It is apparent that
thermocouple 5 consistently sees a lower temperature than the other
three thermocouples which are in the same horizontal plane.
It was initially assumed that perhaps insufficient insulation at
the ends of the heat transfer element allowed heat losses which
caused the variation in thermocouple 5.
However, the ends area is
only 5% of the total area in contact with the
liquid nitrogen.
There-
fore, even if the ends were in the nucleate boiling region, the large
temperature difference can not be explained by end losses.
The
data were reporducible as shown in Figure 6, which includes five
independent runs.
The thermocouples were calibrated in place after
the data was taken and no defective thermocouples were found.
II
1-1/2----,
"'
I
·t········-···-·-··-··············!
••-••
a
• • • • • . , _ , . . , _ . . . . . . . . . . . . . . . ...
r--
II
1
--,
r:::::·::::::~:.::~~::·~
~
I
F" C"-"'"'
A
B
C
D
E
F
-
Thermocouple
Thermocouple
Thermocouple
Thermocouple
T1:er m ocouple
Thermocouple
1
5
2
3
6
4
'~
"~=~·--
:::y-
£-.:.::: ::-_:_~-...-_..:~~~~
311
Figure 5: Drawing of Heater (Outer Surface
only), showing the position of six
thermocouples.
N
00
29
TC-1 Run 5, 6, 7, 8, 9
& TC-3 Run 5, 6, 7, 8, 9
\;} TC-6 Run 5, 6, 7, 8, 9
8 TC-5 Run5,6,7,8,9
-$- Burnout Point
0
36
34
32
3o
r
"
28
~
26l
24
22
N
....;
'4-1
-
~
I
20 '
!-!
...c:
18
;j
....,
~
16
r")
I
0
..--i
14
X
<:
12
a
10
8
6
4
2
0
20
40
60
80
1 0 0 1 2 0 14 0 16 0 18 0 2 0 0 2 2 0 24 0
~T °F
Figure 6.
~T
vs. Heat Flux, Nitrogen Nucleate Boiling
Comparison of TC-1, TC-3, TC-6 with
TC-5.
30
Therefore, it was concluded that there was a temperature gradient
between thermocouples 1, 3, 6 and thermocouple 5.
tigator has reported a gradient of this type.
No other inves-
However, most data
obtained is with only one thermocouple imbedded in the cylinder;
thus, this gradient would not be apparent in previous work.
This
gradient was also apparent along the bottom of the tube as shown by
Figure 7 which compares thermocouple 2 and thermocouple 4.
This
gradient was apparent in all runs although the gradient between
thermocouple 2 and thermocouple 4 became smaller in the later runs.
A comparison of Figure 6 and Figure 7 shows that the radial temperature gradient reported previously by others ( 12, 32) also occurred
in this study.
The only explanation which seems to explain the low
value of temperature that was obtained using thermocouple 5 is that
local surface conditions affect the heat transfer in the area of thermocouple 5.
The surface conditions were changed by adding cutting oil to
the surface, washing the surface with HCl and ethyl alcohol and by
treating it with abrasive cloth.
The surface for runs 5 through 15 was obtained by adding a
thin coating of oil to the heat transfer surface.
heated to 150°F for several hours.
The surface was then
Finally the surface was polished
with 240 grit emery cloth and crocus cloth.
Figure 8 shows the data
(run 5 through 15) for nucleate boiling with the heat transfer element
31
0 TC-2 Run 5,6,7,8,9
8
32
30
TC-4 Run 5,6,7,8,9
t
28
26
24
.
......
.
N
'H
-<
22
20
H
..c:
::I
......
18
~
t""'
16
I
0
X
a
14
12
10
8
6
4
2
0
20
40
60
80
100 120 140 160 180 200 220 240
AT °F
Figure 7.
AT vs Heat Flux, Nitrogen Nucleate Boiling
Comparison of TC-2. with TC-4.
32
in the horizontal, 45° and vertical positions.
Only thermocouple 1
is plotted for these runs since the graph would be exceedingly crowded if all thermocouple readings were placed on the same graph.
Thermocouple 1 was picked because it was the only thermocouple
which was used to determine the burnout temperature difference.
Figure 8 shows that there seems to be little difference in the heat
transfer curve when the heat transfer element is in a different
orientation.
A slight trend for the curve to shift upward and to the
left as the vertical position is approached, is noted.
is very small.
However, this
This agrees with the work of Class, DeHann, Piccone
and Cost (6) for a heater strip made of Drive Harris Co. Karma
electrical resistance alloy 1 inch wide, 0. 005 inch thick and 22 inches
long.
However, it is contradictory to Lyon's (26) work in which he
used 2-3/4 inch outside diameter X 5 inch vertical Copper cylinder
with hemispherical bottom.
At any rate, the orientation seems to
have only a weak effect on the nucleate boiling curve which agrees
with the conclusion of Lyon and Class, DeHann, Piccone and Cost
(6, 26).
Before run 16 the heat transfer surface was lightly washed with
HCl.
Before run 17 the heat transfer surface was thoroughly washed
with HCl, rinsed with water and dried.
After run 17 the heater was
removed and allowed to stand in atmospheric air for two days.
For
some unknown reasons dark spots were formed on the heat transfer
33
Figure 8.
f::J. T
vs Heat Flux, Nitrogen Nucleate Boiling
Comparison of Horizontal, 45° and Vertical
Positions.
34
surface.
They appeared to be due to oxidation.
Runs 18 and 19 were
conducted on the oxidized surface to determine the effect of the deposits on the heat transfer characteristics.
Figure 9 compares runs 16, 17, 18 and 19.
Comparison of runs 5 through 9 and runs 16 and 17, clearly
shows that the HCl washing which changes the surface chemistry
caused the curve to be shifted to the left and upward.
The oxidation
of the surface shown in runs 18 and 19 caused the curve to be shifted
to the right and downward.
Before run 20 the surface was again washed with HCl, rinsed
with ethanol and dried.
Before run 23 the heater was polished with
crocus paper.
Before run 25 the heater was polished with 250 grit
emery paper.
Before run 28 the surface was polished with 240 grit
paper, 100 grit paper and crocus cloth.
Figure 10 compares runs 18 through 27.
Comparing runs 18 and 19 with runs 20 through 2 7 indicates
that the treatment with HCl causes the curve to shift to the left and
upward while changing the surface roughness does not seem to effect
the heat transfer in the nucleate boiling region.
This is in agreement
with Lyon's (26) work.
After run 27, the heat transfer surface was placed 6 inches
away from an infra-red radiant lamp for 4 hours.
After run 28 the
heat transfer surface was coated with a light coat of cutting oil.
35
0
36
TC-1 Run 5, 6, 7, 8, 9
TC-1 Run 16
6
34
0
®
32
-$-
30
28
f*
TC-1 Run 18, 19
TC-1 Run 17
Burnout
Burnout
Burnout
26
24
N
22
....;
.....
20
H
...c:
--.....
;j
......,
18
r:Q
16
('(')
I
0
,_..
~
~
--.....
a
~
I
12
14
. 10
8
6
4
2
0
20
40
Figure 9.
60
80
100 120 140 160 180 200 220 240
AT OF
AT vs Heat Flux, Nitrogen Nucleate Boiling
Comparison After Surface Treatment With
HCl.
36
38
TC-1 Run
TC-1 Run
TC-1 Run
TC-1 Run
TC-1 Run
0
36
6
[J
34
@
~
32
1
••
30
28
26
18,
20,
23,
25,
27
19
21,22
24
26
Burnout
Burnout
Burnout
Burnout
Burnout
24
0
22
.
N
20
......
'H
H
18
...c:
...._
::::!
......
16 -
~
('I')
I
0
14
....-<
X
~
...._
a
12
i
10
8
I
6
4
2
0
10
20
30
40
50
60
70
80
90
100110120
AT °F
Figure 10.
AT vs Heat Flux, Nitrogen Nucleate Boiling
Comparison After Different Surface Roughness.
37
After run 3 0 the heater was again polished with crocus cloth.
After
run 31 the heat transfer surface was covered with a mixture of cutting oil and Fe203.
Figure 11 compares runs 20 through 32.
Comparison of runs 20 through 27 with run 28 indicates that
some change in surface conditions has occurred due to the infra-red
radiation treatment.
This is probably due to some surface reaction
or surface activation due to the radiation.
Comparison of run 28
with runs 29, 30, 31 and 32 indicates that the addition of oil shifts
the nucleate boiling curve downward and to the right.
The maximum temperature differences observed in this lnvestigation are considerably higher than those previously reported {12,
32).
This is probably due to the oil coating which was placed on the
surface initially.
It is felt that the oil filled many of the nucleation
sites; thus, a higher degree of metastability could be obtained.
That
is, for surfaces with smaller number of nucleation sites the maximum
temperature difference will be large.
Table A-XI lists the maximum heat flux and temperature difference for each run where the burnout point was reached. (Seep. 71).
It was found that there was little variation in the maximum
heat flux with varying orientation, surface roughness or by varying
the oil on the surface.
The infra-red radiation treatment seems to
have increased the maximum heat flux at the burnout point markedly.
38
44r----------------------------------------=~----~
0
42
6
40
[J
l
w
6-
36 [
-tp-
38
TC-1 Run 20, 21, 22,23
24,25,26,27
TC-1 Run 28
T C - 1 Run 2 9 , 3 0, 3 1 , 3 2
Burnout
Burnout
Burnout
34.
32 -
30
i
28
26
!
r
l!
i
24 ~
:: [
18
16
I
L
i
~
14
12
f
10
8
6
4
0
10
20
Figure· 11.
30
40
50
60 70
AT OF
80
90
100 110 120
AT vs Heat Flux, Nitrogen Nucleate Boiling
Comparison, after Surface Treatment With
HCl, Oil and Crocus Paper and Infra-red
Radiations.
39
The maximum temperature difference was decreased by treating with HCl and increased by applying a layer of cutting oil to the
surface.
The maximum AT was slightly lowered by increasing the
roughness of the surface, which agrees with the work Corty and
Foust { 7) did.
The AT versus heat flux for liquid nitrogen nucleate boiling
for different pressures {Figure 12) is represented from Park's
work {32).
40
® 14.5 PSI
II
.t. 64
II
X 114
214 II
• 299 II
GJ 389 II
442 II
9.0 ~--
•
'·
-
r
~
7.0
¢0
6.0
N~...
~
114 PSI
I
-
·:
~
"5.0
:)
II,
®
<(
?;
•
4.0
6)
, .
,/
.
/389
i.
3.0
2.0
14.5PSI
6,..
1.0
0--_.--~--._~--~--._--~_.--~--~~~_.--~~
0
1.0 2.0 3.0 4.0 5.0 6.0
7.0 8.0
9.0 10.0 11.0 12.0 13.0 14.0
aT°F
Figure 12.
6T Vs Heat Flux For Nitrogen Nucleate Boiling {32).
41
V.
DISCUSSION OF ERRORS
There are two general types of errors which are important in
nucleate boiling heat transfer studies, the error due to operational
limitations and equipment limitations and the inherent errors which
are found in all nucleate boiling studies.
Previous authors (8, 32}
have found the inherent error to be of the order of 10 to 15%.
The magnitude of the errors due to limitations in operational
procedure and mechanical equipment will be discussed for the heat
flux measurements and temperature measurements.
Experimental
errors can be introduced into the heat flux by inaccurate readings of
current and voltage, neglect of heat loss from the end of the heat
transfer element, inaccurate heat transfer areas, and neglect of the
resistance of the electrical leads.
The heat transfer area uncertainty
and neglect of the resistance of the electrical leads introduces errors
whose magnitudes are small compared to the other factors; therefore,
they can be safely neglected.
The maximum error that can be intro-
duced by neglecting the end effects is equal to the ratio of the area of
the ends to the total surface area and is 5%.
The effects of the end
losses will be certainly less than this figure because of the insulation
which was applied at the ends of the heat transfer surface.
amperage could be read accurately to
could be read accurately to
+ 0.
+ 0.
075 volts.
The
5 amperes, the voltage
42
The thermocouple readings could be read accurately to
millivolts, which corresponds to a temperature of
+ 0. 3
°F.
± 0. 005
The
thermocouples were calibrated in place using fixed points of boiling
liquid nitrogen and ice water (See appendix D).
The corrected tem-
perature differences were felt to be reliable up to
+ 0.
5 °F.
The saturation temperature of the nitrogen was determined
from vapor pressure data (32}.
This introduces an error, but the
magnitude of this error is very small.
43
VI.
1.
CONCLUSIONS
The nucleate boiling region is strongly dependent on the chemical nature of the heat transfer surface.
The micro-roughness
of the surface has only a weak effect on the boiling characteristics in the nucleate boiling region.
2.
Extremely high temperature differences can be obtained in the
nucleate boiling region by application of a thin layer of oil to
the heat transfer surface.
3.
There exists temperature gradients in both the axial and radial
direction for cylindrical surfaces in the nucleate boiling region.
4.
The orientation of a cylindrical heat transfer surface has little
effect upon the heat transfer characteristics in the nucleate
boiling region.
5.
Irradiation of the heat transfer surface with infra-red radiation
seems to effect the nucleate boiling heat transfer characteristics
of the surface by increasing the heat flux requirement for nearly
the same burnout temperature.
44
VII.
APPENDICES
Appendix A - Experimental Data
Appendix B - Sample Calculation
Appendix C - Computer Program for Calculation of Heat Flux and
Heat Transfer Coefficient
Appendix D - Calibration of Thermocouples
Appendix E - Discussion of the Effect of End Losses From the
Heat Transfer Element
45
APPENDIX A
TABLE A-I
Heater: Horizontal Position
Run:
RUN NO. IS
Q/A
.32
.32
.32
.32
.32
1, 2, 3, 4, 5, 6, 7, 8, 9 (Nucleate Boiling N 2 Data)
1
6Tl
6T2
2.10
2.10
2.10
1.90
2.00
l.SO
1.90
1.90
1.80
1.85
6T3
.so
.so
• 70
.so
.so
6T4
1.90
1.80
1.90
1.SO
1.so
AT5
2Sr6
liTM
.so
.as
.90
.15
· .ao
o.oo
o.oo
o.oo
o.oo
o.oo
1.23
1.24
1.25
1.17
1.20
-'
H
266.67
264.SS
263.12
279.91
272.19
IJ:i.
0'
RUN NO.
IS
2
Q/A
6T1
6T2
~T3
6T4
6T5
.6T6
6TM
H
.97
1.48
2.70
3.65
4.65
6.10
7.95
10.95
17.13
7.80
12.40
22.10
29.50
36.10
46.10
58.50
79.20
117.70
6.30
9.80
17.00
21.70
27.60
34.10
41.80
54.80
81.10
3.50
9.60
20.60
28.30
37.20
46.90
58.60
77.70
112.80
7.30
12.30
22.60
30.50
39.00
48.80
57.60
73.80
102.30
4.30
7.80
15.20
20.10
24.90
31.30
38.20
50.60
77.80
1.80
6.60
18.90
26.50
36.10
44.30
58.00
79.00
117.80
5.16
9.75
19.40
26.10
33.48
41.91
52.11
69.18
101.58
189.45
152.60
139.39
140.01
139.15
145.72
152.60
158.35
168.63
~
--.1
3
RUN NO. IS
Q/A
.19
.21
.33
.52
.70
.91
1.14
1. 27
2.05
2.34
2.41
2.72
3.00
6T1
.so
2.00
2.60
6.10
6.60
10.10
10.10
8.60
12.40
13.10
11.90
13.40
13.60
6T2
.85
1.80
2.30
5.50
6.60
8.80
8.75
7. 30
10.10
11.30
10.10
10.60
11.30
6T3
o.oo
o.oo
o.oo
2.00
4.60
6.30
6.10
6.30
8.75
10.50
8.75
9.50
10.50
6T4
6TM
• 70
1.50
2.40
4.60
6.90
9.00
8.80
10.00
10.60
12.30
10.50
12.30
13.30
.58
1.32
... 1 .• 82
4.55
6.17
8.55
8.43
8.05
10.46
11.80
10.31
11.45
12.17
H
339.89
162.52
185.94
114.73
114.13
106.85
135.35
158.07
196.4 7
199.09
234.64
238.23
246.56
~
(X)
RUN NO. IS
Q/A
.14
.52
1.10
1.87
2.34
2.87
4
6Tl
6T2
1.70
2.70
7.80
11.30
13.10
13.30
1.20
2. 60
6.80
10.10
10.60
10.60
6T3
o.oo
o.oo
3.10
8.10
8.60
9.10
6T4
6TM
1.90
2.65
6.80
10.70
11.30
11.80
1.20
1.98
6.12
10.05
10.90
11.20
H
121.81
262.67
180.27
187.00
215.53
256.77
~
...0
RUN NO. IS
5
Q/A
6-Tl
6.T2
6T3
6T4
6T5
b.T6
.97
1.28
1.61
2.64
3.41
4.30
6.96
10.44
19.00
21.50
7.30
10.10
13.10
20.50
25.70
32.30
51.50
75.60
128.40
142.80
6.30
7.90
10.30
15.60
19.30
24.20
37.30
55.00
90.60
99.10
2.60
5.60
9.30
17.40
22.60
30.40
49.90
75.60
121.80
134.90
7.30
10.30
13.60
21.40
27.40
34.80
55.60
82.80
136.60
152.50
5 .--l"o
6.60
9.80
11.80
19.00
24.60
38.80
58.40
97.10
108.80
.90
2.30
5.40
11.80
16.80
23.00
41.80
69.70
120.40
135.10
4.93
7.13
10.25
16.41
21.80
28.21
45.81
69.51
115.81
128.86
6T3
6T4
6T5
~T6
~TM
1.90
6.60
10.80
15.10
31.80
44.10
60.90
82.10
102.60
124.80
145.60
1.60
5.30
8.30
12.30
24.80
34.20
46.20
61.30
78.30
97.20
117.60
RUN NO. IS
6TM
H
198.41
180.10
157.89
161.38
156.82
152.64
152.00
150.19
164.06
166.88
6
Q/A
6T1
6T2
.47
.93
1.48
2.02
4.41
5.97
8.07
11.01
14.71
18.91
23.62
1.60
7.40
11.40
15.40
32.90
44.20
59.50
78.20
107.90
138.40
157.50
2.60
6.30
9.80
13.10
24.30
32.60
43. 10
56.20
72.80
88.80
107.30
o.oo
2.80
7.40
13.00
30.30
42.40
54.60
78.00
98.20
121. 70
144.80
o.oo
o.oo
3.30
7.30
17.30
35.90
52.50
72.30
98.10
123.60
150.50
1.28
4.73
8.50
12.70
26.90
38.90
52.80
71.35
92.98
115.75
137.21
H
368.66
197.84
175.04
159.54
164.11
153.53
152.94
154.44
158.26
163.38
172.20
Ul
0
RUN NO. IS
7
Q/A
~T1
~T2
.6T3
.6T4
~T5
~T6
~™
8.80
13.58
20.00
35.89
66.70
92.90
134.10
200.00
46.00
64.50
91.20
200.00
64.80
90.70
123.80
200.00
57.80
90.60
124.50
200.00
48.80
70.80
101.30
200.00
57.30
89.40
129.60
200.00
56.90
83.15
117.41
200.00
.6T5
.6T6
.6TM
H
154.83
163.40
170 • .40
179.45
Burnout Point
RUN NO. IS
Q/A
~T1
8
~T2
~T3
~T4 ·
H
'
.48
.91
1.50
2.72
4.52
7.60
13.23
21.35
28.97
2.70
6.60
12.90
20.70
33.80
56.80
95.60
146. 10
198.80
2.65
6.10
10.10
16.30
25.80
41.80
68.30
101.80
198.80
Burnout Point
o.oo
2.60
9.10
18.60
32.80
58.30
97.10
144.10
19 8. 80
2.30
6.80
13.30
22.60
37.00
60.80
89.80
130.80
198.80
1.60
5.00
9.30
15.80
26.50
43.30
72.30
108.80
198.80
o.oo
.so
4.30
13.10
33.10
52.30
93.60
139.80
198.80
1.54
4.65
9.83
17.85
31.50
52.21
86.11
128.56
198.80
317.47
196.47
153.20
152.67
143.56
145.57
153.67
166.10
145.74
\.11
RUN NO. IS
Q/A
~T1
9
~T2
6T3
6T4
L\T6
6T5
L\TM
H
~
.91
1.72
3.00
9.39
15.87
20.47
21.88
24.81
28.28
31.63
5.60
11.65
20.30
64.10
107.50
134.40
143.60
164.60
180.80
194.30
4.50
9.30
15.40
45.50
74.00
90.40
96.40
111.90
124.50
194.30
1.60
8.40
18.90
68.75
108.80
133. 70
139.00
155.30
169.70
194.30
5.80
11.80
21.50
68.80
93.60
103.30
110.30
120.80
12 7. 80
194.30
2.70
7.80
15.10
48.30
79.10
99.80
105.40
121.30
136.10
194.30
o.oo
6.60
18.30
73.30
120.70
149.60
157.60
174.10
191.30
194.30
3.36
9.25
18.25
61.45
97.28
118.53
125.38
141.33
155.03
194.30
271.37
186.08
164.77
152.90
163.13
172.74
174.56
175.57
182.43
162.82
Burnout Point
IJl
N
TABLE A-II
Heater: 45° Angle Position
Run:
RUN NO. IS
Q/A
.48
1.00
1.80
3.33
5.81
9.98
12.18
15.29
19.21
. 22.30
24.30
28.63
31.78
32.52
10, 11, 12 (Nucleate Boiling N 2 Data)
10
6T1
6T2
6T3
3.70
9.50
24.50
28.60
45.50
71.90
85.20
111.00
129.60
147.40
158.30
183.00
197.00
198.20
3.60
8.90
16.40
23.60
35.40
53.50
63.00
76.50
92.50
105 .oo
113.00
128.50
140.30
198.20
.10
5.50
15.00
26.80
45.60
75.60
88.00
110.40
131.00
145.70
154.50
172.50
185. 10
198.20
~T4
2.90
9.50
18.80
30.00
48.00
76.90
90.40
110.00
12 a. so
142.00
149.70
165.00
178.40
198.20
6T5
6T6
1.50
6.40
14.30
23.80
35.90
55.90
65.20
81.00
97.00
110.00
118.90
134.30
145.20
198.20
3.70
14.40
26.80
48.30
82.50
97.00
122.50
147.00
167.50
173.70
193.00
195.00
198.20
o.oo
~TM
2.06
1.25
17.23
26.60
43.11
·69.38
81.46
101.90
120.93
136.26
144.68
16 2. 71
173.60
198.20
H
236.82
138.82
104.51
125.41
134.85
143.97
149.52
150.08
158.91
163.66
168.00
175.96
183.09
164.12
Ul
Burnout Point
~
RUN NO. IS
11
L\T3
.6.T4
.6.T5
.6.T6
8. 60
63.70
126.10
176.00
5.50
30.50
69.50
176.00
8.20
42.70
81.00
176.00
7.20
68.90
145.30
176.00
.6T2
L\T3
AT4
8T5
.6.T6
6.00
11.80
21.50
36.60
55.50
73.90
178.30
6.20
16.30
39.50
68.70
103.30
132.80
178.30
9.00
14.10
28.60
45.50
61.70
78.50
178.30
8.90
14.00
29.40
49.40
63.80
88.00
178.30
5.30
15.00
40.80
74.00
96.00
153.30
178.30
Q/A
~T1
~T2
1.75
9.92
21.88
28.87
11.00
68.90
135.00
176.00
6.00
33.00
69.50
176.00
~TM
7.75
51.28
104.40
176.00
H
226.92
193.47
209.65
164.03
Burnout Point
RUN NO. IS
Q/A
1.46
2.33
5.18
9.36
15.45
22.42
29.92
~T1
9.80
17.80
38.00
65.00
103.70
138.20
178.30
12
Burnout Point
.6-TM
7.53
14.83
32.96
56.53
80.66
110.78
178.30
H
194.04
157.38
157.37
165.64
191.56
202.44
167.86
Ul
~
TABLE A-III
Heater: Vertical Position
Run:
RUN NO. IS
13, 14, 15 {Nucleate Boiling N 2 Data)
13
Q/A
~T1
~T2
.43
.95
1.67
3.10
5.42
9.47
16.26
24.43
35.33
1.70
7.20
12.80
22.80
39.40
66.00
100.80
146.50
197.70
1.80
5.80
9.70
17.30
27.70
45.20
68.60
91.30
197.70
~T3
o.oo
2.00
8.30
21.00
40.80
68.20
106.00
138.00
19 7. 70
~T4
1.40
5.00
9.00
15.50
27.00
43.90
62.20
79.00
197.70
~T5
.20
4.90
9.30
18.30
30.50
50.60
78.00
98.00
197.70
~T6
o.oo
o.oo
8.50
21.50
42.20
75.70
120.00
161.00
197.70
~TM
.85
4.15
9.60
19.40
34.60
58.26
89.26
118.96
197.70
H
511.31
231.15
174.97
160.11
156.92
162.67
182.20
205.38
178.71
Burnout Point
U1
U1
TABLE A-IV
Heat Transfer Surface: Treatment With HC1
Run:
RUN NO. IS
16
Q/A
L\Tl
L\T2
.57
.99
1.52
2.23
3.01
4.22
5.64
7.63
10.55
14.02
18.66
24.72
32.03
2.70
6.40
9.40
14.30
19.80
26.80
35.80
47.40
63.40
82.00
103.80
131.70
152.50
2.70
5.30
6.90
11.50
15.00
20.10
26.60
34.70
45.00
56.30
73.00
90.40
152.50
.
16, 17, 18, 19 (Nucleate Boiling Nz Data)
Burnout Point
L\T3
o.oo
2.00
6.60
12.90
20.00
29.10
40.30
54.20
72.30
94.70
114.20
140.00
152.50
LlT4
6T5
1.70
3.50
6.60
9.60
15.90
19.70
26.60
34.90
44.90
56.10
70.60
86.50
152.50
1.00
3.00
5.30
9.00
12.70
17.10
23.70
33.40
42.40
54.50
69.50
87.90
152.50
6T6
o.oo
1.60
5.60
12.50
19.80
29.00
41.00
57.00
76.50
99.00
12 5. 50
140.00
152.50
LSTM
1.35
3.63
6.73
11.63
17.20
23.63
32.33
43.60
57.41
73.76
92.76
112.75
152.50
H
429.25
273.00
226.78
192.52
175.28
178.79
174.62
175.11
183.78
190.05
201.19
219.26
210.05
U1
--.]
RUN NO. IS
Q/A
6T1
.58
1.04
1.50
2.15
2.88
3.73
4.52
5.67
6.98
8.31
10.04
11.92
14.42
2.70
5.20
5.40
5.60
6.90
8.30
9.40
11.60
13.00
15.10
18.00
21.00
23.60
17
6T2
1.80
1.90
2.00
2.60
3.10
4.00
4.50
5.10
5. 50
5.70
7.00
7.20
7.40
LH3
6T4
.6T5
I o.oo
1.90
2.00
2.70
4.00
5.20
5.80
6.80
8.50
9.40
11.60
13.00
15.00
17.80
1.20
1.90
2.00
2.10
3.70
4.70
5.70
6.50
7.60
9.30
10.90
12.60
14.80
o.oo
/
1.00
1.60
3.10
5.10
6. 70
8.50
10.80
13.00
15.20
18.30
22.10
.6T6
o.oo
o.oo
o.oo
o.oo
1. 10
1.90
2.80
5.80
8.10
10.60
14.00
17.20
21.20
6TM
H
1.26
1.83
2.18
2.65
3.85
4.96
5.98
7.66
9.06
10.88
13.01
15.21
17.81
463.67
569.52
687.15
812.64
749.19
752.87
755.83
740.11
770.86
764.02
771.66
783.52
809.83
··~
l1l
CX>
RUN NO.
Q/A
• 55
.85
1.20
1.57
2.03
2.55
3.13
3.86
4.68
5.50
6.73
7.99
IS
18
.6T1
~T2
.6T3
.6T4
~T5
2.50
5.50
5.90
7.50
10.00
12.60
15.10
11 .8o
21.40
24.30
31.60
36.60
3.10
5.10
5. 60
6.50
8.50
10.60
12.30
15.00
16.10
20.80
23.40
25.60
o.oo
1. 70
4. 50
6.30
10.00
12.70
15.60
19.60
23.80
28.80
34.30
41.30
1.60
5.20
5.40
6.30
8.40
10.30
12.40
15.10
17.80
21.00
24.50
28.80
1.00
1.40
2.40
3.20
5.00
6.30
7.70
10.30
13.10
15.00
16.30
18.90
RUN NO. IS
.6T6
o.oo
.20
1.60
5.20
7.40
10.30
. -·14. 20
18.70
23.70
30.60
35.30
38.80
.6T:'1
1. 36
3.18
4.23
5.83
8.21
10.'t6
12.88
16.08
19.31
23.41
27.56
31.66
--~----·--··
H
409.69
269.00
284.10
270.16
247.79
244.09
243.13
240.04
242.63
235.26
244.30
252.61
19
----·--------
Q/A
.6T1
.6T2
.613
.6T4
3.34
4.08
6.33
8.33
11.69
18.12
22.31
32.60
16.90
19.80
28.40
36.40
48.50
70.50
85.20
117.80
12.00
15. 30
21.80
27.40
35.60
49.00
57.80
117.80
17.80
21.80
34.80
52.00
61.30
88.50
10 5. 00
117.80
14.00
11 .8o
26.70
33.50
43.30
60.80
71.00
117.80
Burnout Point
~T5
8.80
10.60
15.60
20.30
2 7.30
40.00
48.30
117.80
~T6
15.40
20.00
33.10
44.30
60.20
8 7. 80
103. 10
117.80
.6TM
14.15
17.55
26.73
35.65
46.03
66. 10
78.40
117.80
------H
236. 58
232.62
236.93
233.72
254.15
274.21
284.67
276.79
U1
...0
TABLE A-V
Heat Transfer Surface: Treatment With HCl, followed by Ethyl Alcohol
Run:
RUN NO. IS
20, 21, 22 {Nucleate Boiling N 2 Data)
20
Q/A
~T1
.6T2
.6T3
.6T4
.6T5
.6T6
L\TM
H
4.21
5.34
8.18
9.18
11.00
13.34
17.17
24.18
30.14
13.10
16.00
23.40
26.90
30.20
40.60
47.60
67.90
85.60
10.60
13.30
18.10
20.30
23.10
27.80
34.80
45.80
85.60
11.20
15.80
24.10
27.60
32.40
38.10
48.30
64.00
85.60
11.20
13.70
20.00
22.10
25.30
29.80
37.10
48.30
85.60
6.60
9.50
13.00
14.60
17.80
9.60
12.80
20.40
23.00
27.80
33.20
41.80
55.00
85.60
10.38
13.51
19.83
22.41
26.10
31.65
39.46
53.10
85.60
406.00
395.41
412.80
409.88
421.65
421.61
435.13
455.50
352.21
20.'~0
27.20
37.60
85.60
Burnout Point
0'
0
21
RUN NO. IS
Q/A
6T1
.6T2
.6T3
.6T4
~T5
~T6
~HI
H
3.66
5.44
7.05
8.55
11.26
15.85
20.75
25.84
37.21
12.90
17.10
21.20
25.60
32.30
44.80
58.10
71.50
91.80
10.30
14.10
16.60
19.70
24.30
32.60
41.20
51.60
91.80
9.30
15.90
20.30
25.50
32.40
45.20
59.20
75.80
91.80
10.00
13.50
17.10
20.90
25.80
34.30
43.80
52.10
91.80
6.10
10.10
11.80
13.50
17.80
24.00
24.50
39.80
91.80
7.60
13.20
17.60
21.30
28.30
39.50
50.60
62.50
91.80
9.36
13.98
17.43
21.08
26.81
36.73
46.23
58.88
91.80
390.92
389.49
404.65
40 5. 60
420.06
431.69
448.85
438.87
405.36
Burnout Point
-
RUN NO. IS
22
Q/A
.6T1
6T2
6T3
~T4
6T5
6T6
.6TM
H
3.82
6.16
8.28
10.96
14.58
16.60
22.34
30.67
12.50
19.00
24.80
31.20
40.50
46.60
61.20
87.30
10.40
14.90
18.90
23.00
29.70
32.60
43.00
87.30
11.40
17.80
18.60
31.00
40.60
44.80
59.10
87.30
9.80
14.70
19.10
24.00
31.10
34.60
44.40
87.30
5.40
9.70
12.50
15.80
19.80
24.10
32.30
87.30
7.60
14.70
19.60
26.80
34.90
40.00
50.90
87.30
9.51
15.13
18.91
25.30
32.76
37.11
48.48
87.30
401.56
407.50
438.08
433.38
445.00
447.49
460.84
351.34
Burnout Point
0'
TABLE A- VI
Heat Transfer Surface: Treatment by Crocus Paper and Sand Paper
Run:
RUN NO. IS
23, 24, 25, 26,27 (Nucleate Boiling N 2 Data}
23
Q/A
~Tl
~T2
~T3
~T4
~T5
.67
1.14
1.64
2.25
3.01
4.00
5.13
6.54
8.48
10.84
13.43
16.91
21.09
2.10
4.70
6.00
8.00
10.40
13.00
15.40
19.30
23.30
28.70
35.70
43.00
53.30
2.70
3.90
5.70
6.40
8.90
10.10
12.80
14.90
18.50
23.10
24.90
31.80
38.30
.60
1. 30
2.50
6.30
9.20
12.70
16.10
21.00
25.20
33.30
41.00
50.10
61.10
2.60
3.80
5.00
6.30
8.80
10.80
13.60
16.20
20.20
24.60
30.30
36.10
43.90
1.00
1.50
2.30
2.90
5.30
6.40
9.60
10.50
13.50
15.90
19.80
24.30
30.20
.6T6
o.oo
.40
1.50
2.50
6.30
9.80
13.60
18.30
24.30
29.00
36.80
45.40
56.00
.6TM
H
1.60
2.60
3.83
5. 40
8.15
10.46
13.51
16.70
20.83
25.76
31.41
38.45
47.13
422.54
440.49
429.00
417.65
369.92
382.69
379.76
39 2. 01
407.21
420.82
427.-,3
440.00
447.48
0'
N
RUN NO. IS
2.4
Q]A
~T1
~T2
.L\T3
.L\T4
.,6T5
,L\T6
.L\TM
2.66
3.66
5.39
7.02
9.15
14.82
18.08
24.03
31.26
11.60
14.60
18.10
22.30
27.60
37.80
47.50
54.80
87.30
8.80
11. 50
15.00
17.80
21.10
29.90
34.60
43.20
87.30
9.00
13.30
19.40
24.10
30.40
46.20
55.30
69.30
87.30
9.40
11.80
15.40
18.50
22.30
32.90
39.00
48.60
87.30
6.20
7.50
10.60
13.30
15.50
22.30
27.30
33.80
87.30
7.70
11.80
16.80
22.30
27.50
42.00
50.80
62.60
87.30
8.78
11.75
15.88
19.71
24.06
35.18
42.41
52.05
87.30
H
303.28
311.62
339.69
356.26
380.29
421.31
426.47
461.85
358.09
Burnout Point
RUN NO. IS
25
Q/A
~T1
~T2
~T3
~T4
L\T5
~T6
L\TM
3.60
4.28
5.53
7.23
9.35
11.97
21.30
28.42
10.70
13.10
15.40
19.80
23.70
31.10
50.20
70.00
9.20
10.30
12.30
15.00
18.40
22.70
36.00
70.00
10.00
13.50
16.90
22.10
27.80
36.60
61.00
70.00
9.90
11.30
14.30
18.00
21.30
2 7. 30
43.30
70.00
5.30
6.30
8.10
10.20
12.30
15.80
27.50
70.00
7.80
10.30
14.50
18.20
24.40
32.30
54.70
70.00
8.81
10.80
13.58
17.21
21.31
27.63
45.45
70.00
·------·
H
408.42
396.50
40 7. 40
420.43
438.87
433.30
468.65
406.09
0'
w
Burnout Point
RUN NO. IS
Q/A
26
6.T1
D.T2
D.T3
D.T4
.6T :;
l\T6
.6T~l
H
·--·"-·
3.19
5.20
6.13
8.98
11.30
15.06
19.52
30.16
10.70
15.00
17.90
22.80
29.80
37 .so
48.60
70.50
9. 20
11.90
13.70
18.30
23.00
28.30
35.30
70.50
9.10
15.30
18.40
26.80
33.80
44.50
57.40
70.50
8.60
12.80
14.80
20.00
24.80
32.30
40.60
70.50
5.20
6.80
8.30
11.80
15.00
19.30
24.60
70.50
6.50
13.20
16.00
23.00
30.80
40.70
52.20
70.50
8.21
12.50
14.85
20.45
26.20
33.76
43.11
70.50
389.32
416.60
413.43
439.41
431.52
446.20
452.92
427.92
Burnout Point
RUN NO. IS
21
Q/A
.6T1
.6T2
6T3
6T4
D.T5
.6T6
6TM
3.82
8.02
11.22
15.53
19.95
28.08
11.20
21.30
28.30
38.10
47.80
68.80
9.80
16.30
21.10
27.60
34.00
68.80
12.00
26.10
36.30
48.80
62.00
68.80
10.50
19.90
27.50
34.20
43.80
68.80
5.30
10.80
15.00
19.50
10 .oo
23.60
32.10
40.40
58.30
68.80
9.80
19.66
26.71
34.76
45.21
68.80
25.t~o
68.80
H
389.95
408.13
420.10
446.73
441.28
408.14
Burnout Point
0'
H:>-
TABLE A- VII
Heat Transfer Surface: Treatment by Infra-red Radiation
Run:
RUN NO. IS
28 (Nucleate Boiling Nz Data)
28
Q/A
~T1
~T2
~T3
.6T4
~T5
~T6
~TM
3.94
5.08
9.68
13.81
18.03
28.48
40.87
6.70
8.50
14.10
19.40
24.50
40.50
66.80
6.20
7.00
10.70
14.50
18.00
28.00
66.80
4.00
5.90
13.90
19.40
26.30
43.50
66.80
6.60
8.00
14.40
18.80
24.30
36.10
66.80
2.80
3.30
6.00
8.20
10.50
18.00
66.80
1.80
3.90
12.00
17.50
23.50
38.80
66.50
4.68
6.10
11.85
16.30
21.18
34.15
66.75
H
841.48
833.37
817.24
847.55
851.24
834.08
612.39
Burnout Point
C1'
U1
TABLE VIII
Heat Transfer Surface:
Treatment by Cutting Oil
Run: 29, 30, 31 (Nucleate Boiling Nz Data}
RUN NO. IS
29
Q/A
~Tl
~T2
~T3
4.27
6.20
9.74
13.61
17.28
21.92
25.45
39.87
11.10
14.90
20.80
27.30
32.80
41.20
46.70
105.30
10. 10
13.10
17.80
22.00
26.40
31.70
35.30
105.30
10.10
15.10
23.80
31.80
39.80
50.70
58.10
105.30
Burnout Point
~T4
11.10
15.10
22.10
28.30
34.40
43.30
49.00
105.30
.6T5
.6T6
.6TM
H
6.10
8.20
11.80
13.80
17.30
20.70
23.50
105.30
7.80
13.30
21.70
29.70
37.40
49.00
56.40
105.30
9. 38
13.28
19.66
25.48
31.35
39.43
44.83
105.30
455.18
466.91
495.30
534.39
551.37
556.07
567.67
378.65
"'
"'
RUN NO. IS
30
Q/A
.6.T1
LT2
LT3
LT4
b.T5
LT6
LTM
4.85
7.66
10.52
16.07
22.40
30.54
50.29
14.80
20.20
26.30
38.10
53.10
74.00
119.30
13.00
16.80
20.90
29.30
40.30
54.30
119.30
14.30
20.50
27.50
38.60
51.30
65.00
119.30
14.30
19.80
25.30
34.60
44.80
56.80
119.30
8.'80
11.80
14.80
20.70
29.00
38.10
119.30
12.90
18.80
26.40
38.50
52.10
6 7.40
119.30
13.01
17.98
23.53
33.30
45.10
59.26
119.30
H
372.99
426.45
447.23
482.87
496.82
515.42
421.54
Burnout Point
RUN NO. IS
31
Q/A
b.Tl
~T2
LH3
b.T4
LT5
b.T6
LTM
H
3.93
4.83
8.52
13.52
19.10
36.83
10 .so
13.30
20.80
31.30
42.70
97.80
10.30
12.90
18.50
26.30
34.10
97.80
9.80
12.70
23.00
34.80
46.50
97.80
11.80
13.70
22.10
32.10
41.30
97.80
6.70
8.90
14.30
21.30
28.60
97.80
7.80
11.00
21.50
33.80
46.00
97.80
9.53
12.08
20.03
29.93
39.86
97.80
413.11
400.18
425.68
451. 71
479.28
376.60
Burnout Point
"'
-.,J
TABLE A-IX
Heat Transfer Surface:
Run:
RUN NO. IS
Treatment by Mixture of Oil & Fe 2 o 3
32 (Nucleate Boiling N 2 Data)
32
Q/A
.6.T 1
.6.T2
.6.T3
3.42
4.69
8.97
15.92
43.22
10.50
13.40
22.60
36.50
100.30
9.80
12.20
19.50
28.70
100.30
7.10
10.70
21.80
36.70
100.30
.6.T4
10.30
12.50
20.30
32.60
100.30
.6.T5
.6.T6
6.10
8.70
15.00
24.10
100.30
6.30
9.60
20.80
36 .. 80
100.30
.6.H1
8. 35
11.18
20.00
32.56
100. 30
H
410.30
420. 14
448.64
488.97
430.97
Burnout Point
0'
()0
TABLE A-X
Film Boiling N 2 Data
Run: 8, 9, 1 0, 12
RUN NO. IS
Q/A
23.16
12.37
4.11
.52
.32
b.T 1
21.01
10.95
3.65
.76
L:>.Tt-\
738.90
596.30
486.60
128.30
94.60
RUN NO. IS
Q/A
8
b.T 1
692.80
634.30
433.00
286.60
738.90
596.30
486.60
128.30
94.60
H
31.35
20.74
8.44
4.06
3.44
9
b.T~1
692.80
634.30
433.00
286.60
H
30.33
17.27
8.43
2.66
.,.,
0'
-.D
Film Boiling N 2 Data
RUN NO. IS
Q/A
2.96
6Tl
6TM
H
435 .oo
435.00
6.82
RUN NO. IS
Q/A
8.12
4.32
10
12
6T1
6TM
H
314.00
250.50
314.00
250.50
25.86
17.28
-...J
0
71
TABLE A-XI'::
Comparison of Heat Flux and Burnout Temperatures for
Different Conditions
Run No.
Condition
Q/A
Btu/hr. ft.2
7
8
9
10
11
12
13
14
15
16
19
20
21
22
24
25
26
27
28
29
30
31
32
Horizontal Position
Horizontal Position
Horizontal Position
45°
Position
45°
Position
45°
Position
Vertical
Position
Vertical
Position
Vertical
Position
Treatment with HCl
Treatment with HCl
Treatment with HCl
followed by Ethyl
Alcohol treatment
Continue
Continue
Treatment by Crocus
paper
Treatment by Sand
paper
Continue
Treatment with 100 grit
240 grit Sand paper
Treatment with infra-red
radiati ons
Treatment with cutting oil
Continue
Treatment with Crocus
cloth
Treatm ent with F e 203
T burnout
OF
35.89
28.97
31. 63
32.52
28.87
29.92
35.33
33.97
32.99
32.03
32.60
200.0
198.8
194.3
198. 2
176.0
178.3
197.7
198.3
191. 7
152.5
117.8
30. 14
85.6
37.21
30.67
31. 26
91. 8
87.3
87.3
28.42
70.0
30. 16
28.08
70.5
68.8
40.87
66.8
39.87
50.29
36.83
105.3
119.3
97.8
43.22
100.3
>!<The runs in which the burnout points are reached are only mentioned
in this table.
72
APPENDIX B
SAMPLE CALCULATIONS
A.
Sample calculation for 1st data points on Run 1.
E = 0. 8 Volts
Data:
I = 6. 3 Amperes
~T
=2. 1 °F
(final result after calibration)
A= 5. 23 x 10- 2 £t.2
1.
Calculation of heat flux.
Q/A = (3. 413 EI)/A = 0. 32 x 10 3 Btu/hr. £t.2
2.
Calculation of heat transfer coefficient.
h
B.
= Q/A~T)
= 266. 67 Btu/hr. ft.2
Sample calculation for ~T from observed millivolts.
Pressure in inches of Hg = 28. 848 inches
= 0. 965 atm.
From Vapor Pressure curve for N2 (32}
~:~
0. 965 atm. -
+ 138. 9 - 460
0
77.2
0
K :: 138.9
= - 321. 9
R (temp. of N 2 )
0
F (reference temp.)
-321.9 °F.!.- 7.81 mV
Data: rn V for Thermocouple 1
-7.81
+ 0.03
+ 7. 78
rnV _;: - 319 °F
= 0. 03
rn V (after calibration)
= 7.78 mV
-·~
.6.T =- 321. 1 OF-(- 319 °F} = 2. 1 °F
*refers to 'corresponds to'
73
APPENDIX C
Computer Program for Calculation of Heat Flux
and Heat Transfer Coefficient
*LIST PRINTER
*ALL STATEMENT MAP
C
CALCULATION OF Q/A HEAT FLUX AND H HEAT TRANSFER COEF.
C
CALCULATION FOR PROJECT 490
DII-'\ENSION DT(6)
READ 102,A
READ 100,L
DO 15 JS=l, L
R2AD 100,K,M,N
P=M
P~INT 500
PRINT 700,N
PRINT 800
PRINT 600
PRINT 900
DO 10 I=1,K
READ 10l,E,CR,(DT(J),J=l,M)
S=O.O
DO 11 J=1,M
S=S+DT(J)
11 CONTINUE
DTi"l=S/P
QA=3.413*E*CR/A
H=QA/DTM
QB=QA/1000.
PRINT 105,QB,(DT(J),J=l,M),DTM,H
10 CONTINUE
15 CONTINUE
CALL EXIT
1 0 0 F 0 Ri"l AT ( 3 I 5 )
101 FORMAT(8F9.2)
102 FORMAT(El8.8)
105 FC.~,·lAT ( 9F9.2)
500 FORMAT(lHl)
T4
T3
T1
T2
600 FORMAT(5X74HQ/A
1 T6
TM
H )
700 FORMAT(4X11H RUN NO. IS,I5)
800 FORMAT(/)
900 FORt-:i\T (I}
END
74
APPENDIX D
Calibration of Thermocouples
All six thermocouples were calibrated using the reference
temperature as that of liquid nitrogen (- 320 °F) for one point and
the reference temperature as that of an ice bath (32 °F) for the other
point.
In each case the heater thermocouples were kept in liquid
nitrogen.
The deviation observed was added algebraically by using
the National Bureau of Standards method (37).
is shown in Figure 13.
The calibration chart
A Leeds and Northrup Company, conversion
table for thermocouples, was used to convert millivolts to temperature.
The millivolt deviations obtained for the thermocouples are given
in the Table D-I.
- - - · - >·-
6
+·o1
0
0
-as"¢--
-Qt
Thermocouple
Thermocouple
Thermocouple
Thermocouple
Thermocouple
Thermocouple
.
---z
_ _ " _ _ _ _ _ _ _ __
, _,.
0--»·.~--------
1
2
3
4
5
6
"".l
:;;;>----11----
6
7
4r6
Correct Reading - Millivolt
~
..-I
0
>
•.-4
..-I
..-I
•.-4
~ 1-·0
I
J-c
0
J-c
J-c
~
rei
1-·OJ
~
~
cU
J-c
,.D
•.-4
..-I
ro
l)
••0}
Figure 13.
Calibration of Thermocouples
-.J
U1
TABLED-I
Millivolt Deviation for Thermocouples
Thermocouple
Liq. Nitrogen
and
Liq. Nitrogen
Ice Water
and
Liq. Nitrogen
Deviation
- 0. 008
+ 7. 843
- 0. 045
- 0. 02
+ 0.
+ 7. 834
- 0. 036
+ 0.
- 0. 034
+ 7. 85
- 0. 052
0. 0
+ 7.
8
- 0. 002
785
+ 0.
1
+ 0.
2
3
4
Deviation
008
034
0.0
02
5
+ 0.
015
- 0. 015
+ 7.
6
+ 0.
04
- 0. 04
+ 7. 825
013
- 0. 027
-J
0'
77
APPENDIX E
Discussion of Effects of the End Losses From
the Heat Transfer Element
Assuming, q
= - KA
dT
dX
holds good as q
= - K.A
.6.T
.6.X
heat
losses from the element were calculated for each set of thermocouples
(Table E-1, E-ll, E-III).
Comparative ly, higher hea t losses wer e
observed than the previous workers (7, 32) observed.
The data were
reproducible and all thermocouples were calibrated with no defective
thermocouple found.
As a conclusion, the possibility of error in
thermocouple readings was eliminated.
The only reason for higher
hea t los se s b etwe en the r m o c ouple 5 a nd thermoc ouple 6, i n whic h
thermoc ouple 5 r e ads low temperatur e throughout the experiment is
due to the possibility of the local surface conditions which affect the
a r e a of thermo c ouple 5.
78
TABLE E-I
Temperature Difference and Percentage Heat Loss at Given
Heat Flux for Thermocouple 1 and Thermocouple 3
(If the axial temperature gradient was due to end losses}.
Run
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
Q/Ax 10 3
Btu/hr. ft.2
0.32
17. 13
3.00
2.87
19.00
18.91
20.00
21. 35
28.28
31. 78
21. 88
22.42
24.43
30.95
27.45
24.72
14.42
7.99
22.31
24. 18
25.84
32. 34
21.09
24.03
21. 30
19.52
19.95
28.48
25.45
30.54
19. 10
15.92
.6.T°F
Heat Input
Btu/hr.
1.2
4.9
3. 1
4.2
6.6
16. 7
10. 3
2. 0
11. 1
11. 3
8. 9
5.4
8.5
19. 7
9.0
11. 0
1.5
2. 7
20.0
3.9
4.3
2. 1
7. 8
14.5
10. 8
8. 8
14.2
3. 0
11. 4
9.0
3.8
. 20
16.7
900. 0
157.0
150.0
1000.0
992. 0
1050.0
115. 0
1470.0
1660.0
1150. 0
1170.0
1270.0
1620.0
1440.0
1290.0
755.0
418.0
1170.0
1260.0
1350.0
1170.0
1105.0
1260.0
1110. 0
1050.0
1080.0
1490.0
1330. 0
1600.0
1000.0
835.0
Heat Loss
Btu/hr.
19. 1
90.0
58.5
79.0
12.3
370.0
194.0
37.6
208.0
212.0
16.7
10.2
15.9
370.0
16.9
206.0
28.2
50.7
376.0
73.4
81. 0
39.4
14.6
272.0
203.0
165. 0
267.0
56.4
214.0
71.4
69.5
3.76
%Heat Loss
114.0
10.0
37.2
52.6
1. 23
37.4
18.5
3.27
14.2
12.8
1. 45
. 87
1. 25
22.8
1. 18
16. 0
3.75
12. 2
32.0
5.8
6. 0
3.38
1. 32
21. 6
. 18. 3
15.9
24. 6
3.78
16. 0
4.45
6.95
. 45
79
TABLE E-li
Tem,eerature Difference and Percentage Heat Loss at Given
Heat Flux for Thermocou:ele 2 and Thermocouple 4
(If the axial temperature gradient was due to end losses}.
Run
Q/A x 10 3
Btu/hr. £t.2
LlT
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
.32
17. 13
3.0
2.87
19.0
18. 91
20.0
21. 35
28.28
31. 78
21. 88
22.42
24.43
30.95
27.45
24. 72
14.42
7.99
22.31
24. 18
25.84
22.34
21. 09
24. 03
21. 3
19. 52
19.95
28.48
25.45
30.54
19. 1
15.92
. 05
21. 2
2. 0
1.2
46.0
36. 0
33.3
29.0
3. 3
38. 1
0.
4.6
11. 3
21. 2
8.9
3.9
10.4
3. 2
13. 2
2. 5
.5
1.4
5.6
5.4
9.3
5.3
9.8
8. 1
13. 7
2.5
7. 2
4. 1
oF
Heat Input
Btu/hr.
16. 7
900.0
157 . 0
150.0
1000.0
992.0
1050.0
115 0. 0
1470.0
1660.0
1150. 0
1170.0
1270.0
1620.0
1440.0
1290.0
755.0
418.0
1170.0
1260.0
13 50. 0
1170. 0
1105. 0
1260.0
1110. 0
1050.0
1080.0
1490. 0
1330.0
1600.0
1000.0
835.0
Heat Loss
Btu/hr.
o/o Heat Loss
.94
400.0
37.6
22.6
865.0
677.0
627.0
545.0
62.0
715.0
0.
86.5
212.0
400.0
16. 7
73.4
195.0
60.0
248.0
47.0
9.4
26.3
10.5
10.2
17.4
99.9
18.4
15. 2
257.0
47.0
13. 5
77.0
5.6
44.5
23.0
15.0
86.5
68.0
59. 7
47.3
4.2
43.0
0.
7.4
16. 7
24. 7
1. 16
5. 7
25.8
14.4
21. 2
3. 72
. 695
2.22
. 95
. 81
1. 57
9.5
1.7
1. 02
19.4
2.94
1. 35
9.23
80
TABLE E-III
Tem;eerature Difference and Percentage Heat Loss at Given
Heat Flux for Thermocouple 5 and Thermocouple 6
(If the axial temperature gradient was due to end losses).
Run
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
Q/A X 10 3
Btu/hr. ft. 2
. 32
17. 13
3.0
2.87
19.0
18. 91
20.0
21. 35
28. 28
31. 78
21. 88
22.42
24.43
30.95
27.45
24.72
14.42
7.99
22. 31
24. 18
25.84
22.34
21. 09
24.03
21.3
19.52
19.95
28.48
25.45
30.45
19. 1
15.92
AT
oF
.8
40.0
23.3
30.4
28.6
31. 0
55.2
50.0
64.3
65.3
63.0
66.0
71. 0
52. 1
4.6
19. 0
54.8
17.4
22. 7
18.6
26.0
28.8
27.2
27.6
31. 9
20.8
32. 9
29.3
17.4
12.7
Heat Input
Btu/hr.
16. 7
900.0
157.0
150.0
1000.0
992.0
1050.0
1150.0
1470.0
1660.0
1150.0
1170.0
1270.0
1620.0
1440. 0
1290.0
755.0
418.0
1170. 0
1260.0
1350.0
1170. 0
1105.0
1260.0
1110. 0
1050.0
1080.0
149 0. 0
1330.0
1600.0
1000.0
835.0
Heat Loss
Btu/hr.
%Heat Loss
15
750
90.0
83.4
436
569
535
580
1030
930
1200
1220
1180
1240
1330
975
86
354
1030
322
425
348
486
540
509
516
597
390
620
550
327
239
43.6
57.4
50.8
50.2
70.0
56.0
104.0
103.0
94.0
76.5
92. 5
75.5
11. 9
85.0
88.0
25.5
31.4
30.0
44.0
42.8
45.8
49.2
55.0
26.0
46.5
34.4
32.7
28.8
APPE NDIX F
Pressure
,_·1ge
~~
Outlet~
~Ammeter
Resistance Box
~
Liquid
Nitrogen
Tank
Liquid
Nitrogen
Dewar
Switch
element
~
Voltmeter
~
Welder
Power Supply
Figure 14: Schematic Drawing of Electrical Circuit
for Experimental Work
00
0
~
81
BIBLIOGRAPHY
1.
Briggs, as reported by Park, E. L., Jr., Ph. D. Thesis,
University of Oklahoma, 1965.
2.
Cobb, Calvin ?-nd Park, E. L., Jr., "Correlation of the Maximum
Heat Flux and Temperature Difference in the Nucleate Boiling
of Corresponding States Liquid!' Unpublished Paper to be
presented at 1966 Cryogenic Engineering Conference.
3.
Chang, Y. and Snyder, N. W., ''Heat Transfer in Saturated Boiling
Under Pressure',' C. E. P. Symposium Series, No. 30, Vol. 56,
1963, p. 25.
4.
Cichelli, M. T. and Bonilla, C. F. , ''Heat Transfer to Liquids
Boiling Under Pressure~' Tras. A. I. Ch. E., Vol. 41, 1945,
p. 755.
5.
Clark, H. B., Strenge, P. S., Westwater, J. W. ,"Active Sites
for Nucleate Boiling, Heat Transfer',' C. E. P. Symposium
Series, Vol. 55, 1959, p. 103.
6.
Class, C. R., DeHaan, J. R., Piccone, M. and Cost R. B.,
Boiling Heat Transfer to Liquid Hydrogen from Flat Surfaces,"
Advances in Cryogenic Engineering, Vol. 5, 1960, p. 254.
7.
Corty, C. and Foust, A. S., "Surface Variables in Nucleate Boiling;'
Heat Transfer, Symposium Series, Vol. 51, 1955.
8.
Drew, T. B. and Hoopes, J. W., Advances in Chemical Engineering,
Vol. 2, Academic Press, Inc., New York, 1958, p . 3.
9.
Flynn, T. M., Draper, J. W. and Roos, J. J. , "The Nucleate and
Film Boiling Curve of Liquid Nitrogen at One Atmosphere."
Advances in Cryogenic Engineer ing , Vol. 7, 1962, p. 539.
10.
Forster, K. E. and Grief, R., ''Heat Transfer to a Boiling Liquid,
Mechanism and Correlations!', J. of Hea t Tr ansfer , Vol. 81,
Feb. 1959, p. 43.
11.
Forster, K. B. and Zub er , N., "Dynamics of Vapor Bubbles and
Boiling Heat Transfer',' A. I. Ch. E. J. , Vol. 1, 195 5 , p. 53 1.
12.
Frederking, T. H. K., Advances in Cryogenic Engineering, Vol. 8,
1963, p. 489.
82
13.
Gartner, R. F. , ''Photographic Study of Nucleate Pool Boiling on
a Horizontal Surface:' Paper presented at A. S.M. E. Meeting
Philadelphia, Nov. 1963.
14.
Gartner, R. F. and Westwater, J. W., ''Population of Active Sites
in Nucleate Boiling Heat Transfer:' Heat Transfer Symposium
Series, Vol. 56, 1960, p. 39.
15.
Githinji and Sabersky, ''Some Effects of the Orientation of the
Heating surface in Nucleate Boiling',' J. of Heat Transfer,
Nov. 1963, reported in Nuclear Science Abstracts, Vol. 18,
Jan. July, 1964.
16.
Griffith, P. J. and Wallis, J.D., "The Role of Surface Conditions
in Nucleate Boiling~' Heat Transfer C. E. P. Symposium Series,
Vol. 56, 1960, p. 49.
17.
Hamburger, L. G., "On the Growth and Rise of Individual Vapor
Bubble in Nucleate Boiling',' International J. of Heat and Mass
Transfer, Vol. 8, No. 11, Nov. 1965.
18.
Hara, T. (Tokyo}, International J. of Heat, Mass Transfer,
Nov. 1963, reported in Nuclear Science Abstracts, Vol. 18,
Jan. July 1964.
19.
Hirchfelder, as reported by Moore, F. D. and Mesler, R. B.,
A.I.Ch.E. J., Vol. 7, Dec. 1961, p. 620.
20.
Hospeti, N. B., Personal Communication.
21.
Kutateladze, S. S., Heat Transfer in Condensation and Boiling,
Translation Series, United States Atomic Energy Commission,
AEC-tr-3770.
22.
Ibele Warren, Modern D evelopm ents in Heat Transfer, Academic
Press, 1963, p. 85.
23.
Jacob, As reported in Gartner and Westwater, Heat Transfer
Symposium series, Vol. 56, 1960, p. 39.
24.
Levy, S., "Generalized Correlation of Boiling Heat Transfe r!'
J. of Heat Transfer, Vol. 81, Feb. 1949, p. 37.
25.
Lienhard, J. H. and Schrock, V. E., "The Effect of Pressure,
Geometry and the Equation of State upon the Peak and Minimum
Boiling Heat Flux;' J. of Heat Transfer, Vol. 85, 1963, p. 261.
83
26.
Lyon, D. N. , "Peak Nucleate Boiling Heat Fluxes and Nucleate
Boiling Heat Transfer Coefficient for Liquid N 2 , 0 and their
Mixtures in Pool Boiling at Atmospheric Pressuref C. E. P.
Symposium Series, Oct. 1964, p. 1097.
2 7.
Madej ski, J. , "Theory of Nucleate Pool Boiling;' Int. J. of Heat
and Mass Transfer, Vol. 8, No. 1, Jan. 1965, p. 155.
28.
McAdams, Addams and Rinaldo, ''Heat Transfer from Single
Horizontal Wires to Boiling Water;' C. E. P. Symposium Series,
Vol. 44, No. 8, 1948, p. 639.
29.
McAdams, W. H., ''Heat Transfer from Single Horizontal Wires
to Boiling Liquids;' Chern. Engr. Progress, Vol. 44, 1948,
p. 639.
30.
Merte, H. and Clark, J. A. , "Boiling Heat Transfer Data for
Liquid Nitrogen of Standard and Near-Zero Gravity;' Advances
in Cryogenic Engineering, Vol. 7, 1962, p. 546.
31.
Moore, F. D. and Mesler, R. B. ,"The Measurement of Rapid Surface Temperature Fluctuations during Nucleate Boiling of
Water~'A.I.Ch.E. J.,
Vol. 7, Dec. 1961, p. 620.
32.
Park, E. L., Jr., "Nucleate and Film Boiling Heat Transfer to
Methane and Nitrogen from Atmospheric Pressure to the
Critical Pressures;' Ph. D . Thesis 1965, University of
Oklahoma.
33 .
Perry, J. H., Chemical Engineer's Handbook, McGraw Hill
Company, New York.
34.
Rohsenow, W. M., Modern Developments in Heat Transfer,
Edited by Ibele Warren, Academic Press, 1963, p. 89.
35 .
Roll and Myers, "The Effect of Surface Tension on Factors in
Boiling Heat Transfer;' C. E. P. Symposium Series, July 1964,
p. 530.
36 .
Strange , Or ell and W estwat er , "Microscopic Study of Bubble Growth
during Nucleate Boiling;' C. E. P. Symposium Se ri e s, Dec. 196 1,
p. 578.
37.
Temperature, ''Its Measurement and Control in Science and
Industry;' National Bureau of Standards, Reinhold Publishing
Corpora tion, U. S. A.
84
38.
Westwater, J. W., Advances in Chemical Engineering, Vol. 1,
Edited by Drew, T. B. and Hoopes J. W., Academic Press,
Inc. Publishers, 1958.
39.
Young, R. K. and Hummel, "Improved Nucleates Boiling Heat
Transfer;' C. E. P. Symposium Series, Vol. 60, No. 7,
July 19 64, p. 53.
40.
Zuber, reported in Lienhard and Schrock, J. of Heat Transfer,
Vol. 85, 1963, p. 261.
85
IX.
VITA
The author of this thesis, was born on October 14, 1941 in
Bombay, India.
He received his primary education in The Modern
School, Bombay.
He attended then St. Xavier's College, University
of Bombay and received his college education.
In June 1960, he
attended the College of Technology, Banaras Hindu University,
Varanasi, India and received his degree of Bachelor of Science 1n
Chemical Engineering and Chemical Technology in May 1964.
In September 1964 he enrolled as a candidate for degree of
Master of Science in Chemical Engineering at the University of
Missouri at Rolla.
He was appointed as a laboratory assistant by
the Department of Chemistry, U. M. R. during the Fall, 1965-66.