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A study of the nucleate boiling heat transfer coefficient of dichlorodifluoremethane (Freon-12) over… Tang, Shih-I 1965

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A STUDY OP THE NUCLEATE BOILING HEAT TRANSFER COEFFICIENT OF DICHLORODIFLUOROMETHANE (FREON-12) OVER A HORIZONTAL SURFACE by SHIH-I TANG B.E., National Southwest Associated University, 1943 A THESIS SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF APPLIED SCIENCE i n the Department of Mechanical Engineering We accept this thesis as conforming to the required standard  THE UNIVERSITY OF BRITISH COLUMBIA JUNE, 1965  In p r e s e n t i n g  t h i s thesis i n p a r t i a l fulfilment of  the r e q u i r e m e n t s f o r an advanced degree a t t h e British  Columbia, I agree t h a t the  a v a i l a b l e f o r reference  and  study.  University  of  L i b r a r y s h a l l make i t f r e e l y I f u r t h e r agree t h a t  permission  f o r e x t e n s i v e copying o f t h i s t h e s i s f o r s c h o l a r l y purposes may g r a n t e d by  the  Head o f my  It i s understood t h a t f i n a n c i a l gain  Department o f  s h a l l not  be  a l l o w e d v;ithout my  Mechanical Engineering  June 25,  representatives.  copying or p u b l i c a t i o n of t h i s t h e s i s f o r  The U n i v e r s i t y o f B r i t i s h Vancouver 8, Canada. Date  Department o r by h i s  be  Columbia,  1965.  written  permission.  ii.  ABSTRACT The heat transfer coefficients f o r o i l - f r e e liquid dichlorodifluoromethane  (Preon-12 or Genetron-12) i n nucleate boiling over a  horizontal copper surface were measured at saturation temperatures of 0°F and 25°F and at heat flux densities between 6,000 and 63,000 2 Btu/hr-ft .  The heating surfaces were finished with 400-A emery  paper i n two different patterns before each series of test-runs, while the geometric arrangement and the other parameters of the apparatus remained unchanged. and photomicrographs  Profilometer measurements of roughness  of the surface were taken.  A l l the boiling  curves calculated and plotted from the experimental results were of "S" shape, revealing a pronounced deviation from the conventional (normal) boiling curve, especially at lower saturation temperatures. The deviation of the boiling curve was probably due to the unpredictable nucleating characteristics of the heating surface and of the bubble population [ l , 2~\.  This makes i t impossible to correlate the  experimental data by any of the existing empirical equations formulated by Zuber [3, 4, 5 ] ,  Rohsenow[6, 7 ] ,  Levy[l6] and others.  iii. CONTENTS I. II.  Page 1  Introduction Theory  2  2.1  General  .  2  2.2  Factors Affecting Nucleate Boiling  6  2.3  Correlations of Boiling Heat Transfer Data  8  2.4  Unknown Factors i n Boiling Heat Transfer  ...  1 3  III.  Experimental Apparatus  15  IV.  Experimental Procedure  24  Calculations  28  V. •VI.  Discussion of Procedure  VII.  Analysis of Test Results  VIII. IX. X.  32  Conclusions  4 2  Suggestions for Modification of Apparatus Appendices Appendix Appendix  Bibliography  ....  4 3  4 4 I. Sample Calculations  4 4  I I . Test Data of Refrigerant Dichlorodifluoromethane (Genetron-12)  Appendix I I I . XI.  3 0  List of Equipment and Instrumentation  .  46 5 4 5 6  I T .  LIST OP FIGURES  liSHre  Page  1.  Analysis of boiling curve  2  2.  Pool boiling apparatus  16  3.  Diagram of experimental apparatus  17  4.  Heating surface assembly and wiring diagram of instrumentation  19  5.  Heating surface assembly  20  6.  Instrumentation layout  22  7.  Finish patterns of copper heating surface  25  8.  Photomicrographs of 400-A polished copper heating surfaces Comparison between Stephan's, Furse's and author's experimental results ...  25  9. 10.  Boiling curve of high-low-high heat flux densities  33 34  o  11.  12.  13.  o Boiling curve of Genetron-12 at 25 F and O F saturation temperatures (parallel-line f i n i s h pattern)  35  Boiling curve of Genetron-12 at 25°F and 0°F saturation temperatures (cross-line f i n i s h pattern)  36  Effects of heat transfer coefficient by thin layer of o i l on heating surface  37  LIST OP SYMBOLS Nomenclature: A  =  heating surface area  C  - C = s p e c i f i c heat at constant pressure P  0  =  3X  C , C d  =  coefficient of Equation,. ( 3 ) = constants of Equation (9)  2  diameter of heating surface  D, = b  diameter of bubble  =  mass velocity of bubbles  h  =  H  k  =  thermal conductivity  K  =  =  boiling heat transfer coefficient  coefficient of Equation (7)  Si  Nu = , b  bubble Nusselt number  Nu = br  bubble Nusselt number defined by Equation ( 4 )  Nu^^ = P  bubble Nusselt number defined by Equation (6)  =  pressure  Pv =  pressure i n vessel above liquid  Pr_ = P/Q Q  l i q u i d Prandtl number  = =  =  C H< EL  percentage difference between Q and  heat transfer rate from heating surface  Q = w  QW  Q/A = R  =  =  heat input rate by wattmeter  the rate of heat transfer per unit area of heating surface bubble radius  Re, =  bubble Reynolds number  D  Re. = br  bubble Reynolds number defined by Equation  Re^ =  bubble Reynolds number defined by Equation (6)  z  T T  =  l'  T  (4)  temperature  2' 3' T  4  T  a  n  d  T  5  =  temperatures of thermocouples 1, 2, 3, 4 and 5 respectively  T 7 T  g  = =  T^ = AT W  room temperature, temperature of thermocouple 7 = Tg = mixed bulk temperature or saturation temperature of l i q u i d temperature of heating surface  = DELT = =  T - T, w b  power input by wattmeter  x , x , x ,x  and x  =  =  mass density  =  dynamic viscosity  Subscripts: L  =  liquid  distances to thermocouples 1, 2, 3, 4 and 5 respectively from surface  vii.  ACKNOWLEDGEMENT The author wishes to acknowledge the invaluable guidance and supervision of Dr. Zeev Rotem during the course of this study. In particular, the author would like to express gratitude for the enthusiastic counsel and physical assistance given by Professor W. 0. Richmond and Dr. C. A. Brockley. The author i s also indebted to the technicians i n the Department of Mechanical Engineering f o r their help and suggestions during the course of experimentation. The author i s pleased to acknowledge the assistance rendered to the project by Dupont of Canada Limited who furnished the techn i c a l data on dichlorodifluoromethane. F i n a l l y , the author wants to thank Mr. P. G. Purse for i n i t i a t ing the project which was supported by funds from the National Research Council through a Grant-In-Aid of Research originally awarded to Mr. P. G. Purse (NRC A-1660). designed by Mr. Purse.  The apparatus used was  I. INTRODUCTION  The nucleate boiling region i s of great practical interest because a high heat flux density  can be accommodated at a small,  temperature difference between the heating surface and boiling l i q u i d .  the  P r a c t i c a l applications of boiling heat transfer  theory are found i n high power density systems, such as nuclear reactors, rocket engines, space power plants, etc. A considerable amount of research on boiling heat transfer has been conducted and the results have been published, but  few  of these were carried out on boiling of the refrigerant dichlorodifluoromethane (Preon-12 or Genetron-12).  Since Preon-12  i s a common widely used refrigerant for air-conditioning  and  refrigeration systems, the investigation of the b o i l i n g of such a refrigerant i s of practical interest. results may  Also, the experimental  be used for the design of evaporators or heat  exchangers. There are a large number of parameters which w i l l affect the heat transfer rate. intention was  In the experimental work described  here the  to concentrate upon the investigation of a few  of  these factors, namely, (l) the effect of surface f i n i s h texture on the heat transfer, (2) the effect of surface roughness on the heat transfer rate. In order to arrive at a more quantitative understanding of the boiling phenomena, the effects of ageing of the heating surface of hysteresis were also observed throughout the investigation.  and  II. THEORY  2.1. r  GENERAL  i *  In 1934, Nukiyama [10 j made a simple experiment by submerging a thin platinum wire i n water and heating the wire e l e c t r i c a l l y to produce boiling.  Later, numerous similar experiments on boiling  heat transfer for different kinds of liquids were conducted by many investigators.  According to Farber and  Scorah's  investigation [ 2 l ] ,  boiling proceeds i n several distinct regimes which w i l l be discussed later. Boiling heat transfer may be investigated i n two ways: ( l ) by experimental methods and (2) bv analysis.  Most investigators have  used experimental methods i n which the coefficient of heat transfer i s obtained as a function of temperature difference between the heating surface and the boiling liquid with l i t t l e attention being paid to obtaining fundamental information of the phenomenon.  Thus  l i t t l e information i s obtained which i s generally valid for a p a r t i cular s o l i d - l i q u i d combination at a specific saturation temperature. Contributions of a more fundamental nature by Jakob [20], and his co-workers are of great significance.  They searched for the. mecha-  nism of boiling of a l i q u i d by observing photographically the generation of bubbles on the heating surface and the characteristic features of the bubbles r i s i n g through the l i q u i d mass. V i r t u a l l y a l l attempts at analysis of the nucleate boiling phenomenon proceed semi-empirically.  The problem i n i t s entirety i s  of a complexity such that a reasonably general a n a l y t i c a l model,even i f i t could be developed, would net lead to useful and lucid * Numbers i n square brackets refer to numbered references i n the Bibliography.  3.. result's.-  Ail- models proposed' aim at' the reproduction of a boiling 1  1  curves i^.e., a plot of the heat transfer coefficient (h) versus the temperature  difference between the heating surface and the saturation  temperature  of the l i q u i d , of a. general shape shown i n Fig.. 1 £ 2 1 ]  1  Fig; 1 * Analysis of boiling curve (after Farber and Seorah  .  £21]).  Generally, boiling processes take place i n three types [ 7 , 9, 11, 12]: a.  Nucleate boiling.  b.  Transition.  c.  Film boiling.  The boiling curve suggested by Farber and Scbrah Q?l] generalizes the boiling phenomenon into six regimes as indicated i n F i g . 1: , Regime  I:  Interface evaporation - Liquid i s being heated by natural convection.  Heat i»s transferred by pure  convection, and vaporization without boiling occurs only at the vapor-liquid interface.  The onset of  convective heat transfer i n this region i s essent i a l l y a c l a s s i c a l i n s t a b i l i t y problem. Regime II: Nucleate boiling - Bubbles begin to form at active nuclei on the heating surface and grow larger as the temperature  difference ( A T ) increases. When the  buoyant force of the bubble overcomes the adhesion force to the heating surface, bubbles break off and rise through the pool inducing a convection current. As bubbles r i s e , some combine into larger bubbles, and others rise individually, but a l l disappear i n the superheated liquid before they reach the l i q u i d vapor interface. same sites.  Bubbles continue to form on the  In this nucleate boiling region the  e b u l l i t i o n i s not vigorous.  5Regime III:  Nucleate boiling - Vigorous boiling takes place. great number of larger bubbles ascend,-  A  through the  superheated l i q u i d and rise into the a i r as vapor at the liquid-vapor interface.  The s t i r r i n g action pro-  duced by r i s i n g bubbles i n turn increases the heat transfer rate.  This i s the most e f f i c i e n t heat transfer  region, and i s therefore the condition aimed at i n design. Regime  IV:  Transition - An unstable film forms over the heating surface but periodically collapses and forms again. Since the heat flux rate decreases with further i n crease i n surface temperature, this part of the b o i l ing curve i s essentially  Regime  unstable.  V:. ..Film boiling - The f i l m of vapor over the heating surface does not collapse,but becomes stable.  Due  to the rapid formation of large bubbles, the outside surface of the vapor film i s continuously agitated and moves rapidly i n wave form. Regime  VI:  Film boiling - A stable vapor f i l m remains over the heating surface.  Bubbles appear to form at the surface  of the film instead of at the nuclei on the heating surface.  In this range, heat i s transferred through  the vapor film by conduction and radiation.  2.2  FACTORS AFFECTING NUCLEATE BOILING  There are numerous variables which w i l l affect the boiling heat McAdams [l2] , Westwater [_9 ] and Hsu [_7 ] com-  transfer coefficient.  piled many of the previous investigations.  The predicted parameters  are as follows: a.  Physical Properties of the Liquid - Surface tension, thermal conductivity, density, viscosity, latent heat, impurities, etc., are the parameters affecting the heat transfer rate.  b.  Condition or Texture of Heating Surface -  The rate of  heat transfer i s higher for rough and clean surfaces than for smooth and old surfaces. c.  Material of Heating Surface - According to a series of experiments conducted by Agarwal and Hsu [7 ] , copper gives better "h" than chromium, platinum, nickel or zinc.  d.  Temperature of the Liquid - Generally, the boiling film coefficient increases with the temperature of the l i q u i d .  e.  Pressure - The temperature difference necessary to maintain a given heat flux decreases as pressure increases.  f.  Geometric Arrangement -  The equations of Rohsenow \_6 ]  and of Forster and Zuber [14] do not predict the influence of the geometric arrangement - which may be of some consequence. g.  Agitation -  Agitation induced by r i s i n g bubbles or by  mechanical means w i l l increase any given temperature  the heat transfer rate at  difference.  Short-Wave Irradiation - The rate of nucleation i s affected strongly i f the l i q u i d i s easily ionized or the l i q u i d i s a poor conductor.  8. 2.3 a.  CORRELATIONS OF BOILING HEAT TRANSFER DATA  Concepts In the past few decades, research on boiling heat transfer has  been conducted by many investigators.  The models of boiling pro-  posed are summarized as follows: (1)  Jakob [ 2 0 ] proposed that the vapor bubble of boiling  originates i n a thin highly superheated layer of l i q u i d near the heating surface.  A bubble cannot originate from zero radius and  boiling w i l l not start unless curvatures are present, such as are formed by wall roughnesses or by gas bubbles and other impurities i n the l i q u i d .  The degree of superheating of a boiling liquid w i l l  depend upon the s t a t i s t i c a l mean of the radius of curvature of wall roughnesses or of bubbles of gas adhering to the walls on which the l i q u i d can evaporate.  The process of originating and growing of  vapor bubbles causes some motion of the l i q u i d and therefore promotes the heat transfer on the heating surface. (2)  Gunther and Kreith [22~] showed the existence of a  highly superheated film next to the heating surface.  The high  thermal resistance of this f i l m Is removed by the growth and collapse of vapor bubbles.  Radial velocity of growing vapor  bubbles and superheated f i l m thickness next to the heating surface can account for the heat transfer rate. (3)  E l l i o n [ 2 3 ] suggested that at higher superheats the  diameter of a bubble at departure i s governed by a mechanism which indicates the importance of the r a d i a l velocity of a bubble while i t i s s t i l l attached to the heating surface.  9. (4)  Corty and Foust [13] demonstrated the importance of the  size and distribution of the micro-roughness i n determining the l i q u i d superheat and boiling heat flux.  This means that by chang-  ing surface characteristics the shape of the nucleate boiling curve can be changed. In conclusion, these experimental findings seem to indicate that the large heat transfer rate associated with nucleate b o i l ing i s a consequence of the micro-convection i n the super-heated sublayer caused by bubble b.  dynamics,  Empirical Equations Heat transfer data f o r pool boiling have been correlated using  a bubble NusseIt number (Nu^), a bubble Reynolds number (Re^), and the Prandtl number (Pr ) of the l i q u i d . T  Upon application of the  theory of s i m i l a r i t y to the d i f f e r e n t i a l equations of heat transfer and f l u i d flow, a relation of the form Nu  b  = j6 (Re ,Pr ) b  —  L  (l)  may be shown to exist f o r the heat transfer from a solid boundary to a f l u i d .  An approximate form of the function 0 may be obtained  from experimental data, and f o r purposes of design, an empirical expression of the form Nu = b  Coeff. ( R e ) ( P r ) m  b  L  n  -  (2)  i s usually employed. In 1951, Rohsenow [6] developed an equation expressed i n the form of equation (3) by correlating experimental data from near inception of nucleate boiling to the maximum heat-flux values over a wide range  10. of pressure and for various surface-fluid combination  br where Re  (3)  C ' br' sf  <V (»„>  br  (4). (Q/A) (D ) B  Nu.  (T  br  w  - T ) (k ) s li  The coeefficient  (C  Si  ) depends upon the surface tensions between  l i q u i d , vapor and solid for a particular surface-fluid combination, i s the diameter of bubble as i t leaves heating surface and  is  the mass velocity of bubbles at their departure from heating surface. In 1955, another correlation employing Equation (2) was derived by Forster and Zuber [4, 14]. It takes the form of Nu = bz  0.0015 (Re, )°- (Pr )0.33 bz L 62  T  (5)  where  Hi  2  Re bz  (6)  N  .  u  bz  ( q A ) (B) (T - T ) (k ) w  s  L  Here R and R are the radius and rate of growth of the bubble respectively. The exponents and coefficient of the Forster-Zuber Equation (5) were derived from peak-value data which cannot correlate the entire  11. nucleate boiling regime.  In order to make the equation v a l i d over  the entire heat flux range, Rohsenow [5] used the data previously taken i n developing Equation (3) to re-evaluate the exponents and /  coefficient of Equation (5). found:-  *s. • V \/ B  The following form of correlation was  - 0 5  K>~  <>  7  7  where K . i s also a function of the surface-liquid sf Table  combination,  I  l i s t s magnitudes of C _ and K . of Equations sf sf (7) f o r some surface-fluid pairs i n pool boiling [5] .  (3) and  Table I Values of C ^ and K . sf sf Fluid-heating surface  C . sf  K _ sf  Water-platinum  0.013  ...  Benzene-chromium  0.010  1  Ethanol-chromium  0.0027  n-pentane-:chromium  0.015  Water-brass  0.006  300 0.30 ...  Several other attempts at correlation of boiling heat transfer have been made, such as Levy's  [l6] .  These a l l use similar methods  but assume different physical models for the boiling process. Actually, they are not complete and should not be compared directly to each other since none of them has taken into account the nucleating characteristics of the heating surface.  Besides, the various  investigators do not even agree on the quantitative and qualitative  12. effects of some of the important variables such as the temperature difference, surface tension, l i q u i d viscosity, etc., i n their derivations. The correlation of the b o i l i n g heat transfer results of the present investigation w i l l be discussed later i n Section VII.  . 1 3 .  2.4  UNKNOWN FACTORS IN BOILING- HEAT TRANSFER  At present, according to Westwater \_23,  we are s t i l l lacking  a complete knowledge of nucleate b o i l i n g because there are some parameters which affect the heat transfer coefficient s t i l l i n need of further investigation and understanding a.  e  These are:  Shape of Nucleate Boiling Curve - From the very beginning  investigators conducting research i n nucleate b o i l i n g have assumed that the nucleate b o i l i n g curve (Q/A V S . A T ) should be a smooth curve with a positive slope at a l l points up to the maximum heat f l u x . However, some recent investigations showed that the curve could be of  " s" shape  9  with a negative slope over part of i t s course.  WestwaterQ>] and Rohsenow[6] suggested  that the deviation of the  boiling curve i s due to the effects of acceleration, the nucleating characteristics of heating surface, and of the bubble population. If this i s true, then a l l the existing equations for nucleate boiling such as those given by Rohsenow, Forster and Zuber, and others can only be a f i r s t b.  ;  approximation.,  Natural and A r t i f i c i a l  Nucleation Sites - Nucleation sites  on the heating surface affect the heat flux.  A great deal of further  investigation i s required to be conducted on: (1)  the best shape of nucleation s i t e s ,  (2)  the best size and distribution of s i t e s ,  (3)  the best material f o r the s o l i d surface,  (4)  an economical way to produce a large number of s i t e s ,  (5)  the expected l i f e of sites for different liquids  14.  under various operating conditions, and (6) c,  the rejuvenation of deactivated s i t e s .  Bubble Growth - Existing knowledge, data and theories, are  s t i l l inadequate regarding the shape of the bubbles, the temperature profile of the l i q u i d i n the region near the bubble wall and near the  solid, wall, and the bubble growth rate. d.  Bubble Frequency - We are s t i l l lacking knowledge on the  number of bubbles emitted per unit time and the bubble sizes as they break away from the heating surface.  To predict nucleate b o i l -  ing heat fluxes existing equations are not valid f o r any s o l i d - l i q u i d combination. In the present investigation the effects of the surface f i n i s h pattern and surface roughness on the heat transfer coefficient received concentrated attention.  III.  EXPERIMENTAL APPARATUS  15. The experimental apparatus (Fig. 2 ) was originally designed by Mr. F. G. Purse f o r measuring the boiling heat transfer coefficients of o i l - f r e e Freon 1 1 and Freon 12-mixtures [ l 5 ] .  It can be used to  measure the boiling heat transfer coefficients f o r any s o l i d - l i q u i d combination within the pressure range from - 5 to 1 0 0 psig.  The  p r i n c i p a l components were a 6 - i n . ID, 6 - f t . high steel pressure vessel, a 2 - i n . diameter e l e c t r i c a l l y heated heating surface assembly, a pool of liquid refrigerant, a condensing c o i l i n the vapor-filled space above the l i q u i d , a temperature measurement c i r c u i t , and a piping system. Heat was provided by three e l e c t r i c a l heaters embedded at the lower end of the heating surface assembly.  Heat input was regulated  by a variable transformer and measured by a wattmeter. A refrigeration plant supplied the cooling effect to the condensing c o i l i n order to control the boiling temperature of the l i q u i d inside the vessel.  Copper-constantan thermocouples were i n s t a l l e d  at various locations to measure the temperature and heat flow during the course of test. A complete l i s t of equipment and instrumentation i s shown i n Appendix III and the principal components are explained i n d e t a i l as follows: a.  Steel Pressure Vessel (PV) - the geometry of the vessel i s  shown i n F i g . 3 .  The vessel was made of 3 / 4 "  safely a boiling pressure of 1 0 0 psig.  steel and could sustain  The 12-mesh bronze screen (BS)  i n s t a l l e d half way between the l i q u i d surface and the condensing c o i l  Pig. 2.  Pool boiling apparatus  17. PG MXV  rr  MM  MGV  -REFRIGERATION PLANT  PV PG  KJ VPC  =txf=  CH  O c=<=HH*H  CHARGING CONN.  MGV  MANUAL GLOBE VALVE  MXV  MANUAL EXPAN. VALVE  VPC  VACUUM PUMP CONN.  z ©SG Rl.P  CH  =C*3=  Pig. 3. Diagram of experimental apparatus  18. was to prevent the disturbance of the boiling mechanism by the f a l l i n g droplets condensed over the cooling c o i l . b.  Heating Surface Assembly (Figs. 4 and 5) - The upper end  of a v e r t i c a l 2-inch pure copper rod was used as a heating surface. The heating surface was polished with 400-A emery paper before each set  of test-runs.  Surface roughness was measured by a calibrated  profilometer and recorded (see Table I i ) .  Three 300-watt e l e c t r i c  heating elements (HE) (0.75 inch diameter, 3.25 inohes long) were • embedded i n the lower end of the copper rod to provide the heat input. The e l e c t r i c heat input was regulated by a 2-kilowatt Variac (Variable transformer, VT) and measured by a wattmeter (WM).  A high limit  thermostatic switch (TLS) was i n s t a l l e d to prevent excessive heat flux.  Four thermocouples TC's 1, 2, 4 and 5 were placed 0.253, 0.704,  1.560  and 3.035 inches respectively below the boiling surface  (Fig.  4).  These thermocouples were embedded i n r a d i a l holes along  the longitudinal axis of the copper rod at specific locations to measure the temperature gradients for calculating the heat flow along the copper rod. rod  Heat leakages were minimized by mounting the copper  i n a 6 inch by 4 inches deep cushion of neoprene rubber  (NP).  Heat leakage was negligible according to a previous investigation by Purse [ l 5 ] . c.  Condensing Goil and Refrigeration Plant (Fig. 3) - The  condensing  c o i l (CC) (installed i n the vapor f i l l e d space above the  l i q u i d l e v e l inside the pressure vessel) was connected to a 3 hp. refrigeration plant outside the apparatus.  The refrigeration plant  was used to provide a cooling effect i n the condensing c o i l i n order  Pig. 5.  Heating surface assembly O  to control the boiling temperature inside the vessel during the course of the experiments. d.  Pool of Liquid Refrigerant Dichlorodifluoromethane  Pig. 3) -  (RLP)  A pool of refrigerant approximately 12 inches deep was  maintained inside the vessel at a l l times.  The thermocouple TC-6  was placed at a position about 6 inches below the l i q u i d surface. This provided a good indication of the bulk temperature of the b o i l ing l i q u i d . e.  Temperature Measurement Circuit (Pigs. 4 and 6) -  Temperatures of the boiling l i q u i d and the temperature gradients along the longitudinal axis of the copper rod were obtained from thermocouples mounted at the points shown i n Pig. 4.  The thermo-  couple reference junction (CRj) was kept i n a mixture of water and crushed ice and a thermometer  (TM-l) was inserted i n the ice bath to  verify that there was a constant cold junction temperature during each test-run.  A l l thermocouple lead wires were e l e c t r i c a l l y shielded  and connected to a Philips Recording Potentiometer (PRP) through a switch panel (SP).  The switch panel was wired i n such a way that  the temperature of any specific thermocouple could be measured by a precision potentiometer (POT) and galvanometer (GAL) unit during the course of a test.  Thermocouple TC-7 was mounted i n direct contact  with a precision thermometer  (TM-2) having 0.05 deg. P. divisions.  The thermometer indicated the ambient temperature and at the same time  provided a check to the recorder reading from thermocouple TC-7. Periodic checks indicated the thermocouple readings were unaffected by the presence of e l e c t r i c a l equipment i n the test area. f.  Valves and Piping System (Fig. 3) - Valves and piping were  arranged so that refrigerant could be charged to, or removed from the vessel.  A i r could be eliminated from the inside of the pressure  vessel by a high vacuum pump (HVP, not i l l u s t r a t e d ) prior to charging with refrigerant.  A pressure gauge (PG), mercury manometer (MM) and  barometer (not i l l u s t r a t e d ) were used to ensure the accuracy of the boiling temperature measurements obtained from Thermocouple TC-6. A sight-glass (SG) was used to indicate the l i q u i d refrigerant level and safety valves (SV) were provided to guarantee safe operation. The steel testing vessel and the lower part cf the heating surface assembly were completely insulated with 2-inch thick Microlite blanket insulation with vapor barrier to minimize the heat loss during the course of the experiment. electrically  grounded.  The entire apparatus was  EXPERIMENTAL PROCEDURE  24. Before each s e r i e s of t e s t - r u n s , the heating surface was p o l i s h e d to the d e s i r e d pattern ( F i g . 7) using No. cleaned with "Ghlorothene"  (CELCGl,,  400-A emery paper and  inhibited  1,1,1-Trichloroethane).  P r o f i l o m e t e r measurements of surface roughness were taken before a f t e r a s e r i e s of t e s t - r u n s .  and  Roughness measurements are shown i n Table  II. The i n s i d e of the pressure v e s s e l was before the apparatus was  assembled.  cleaned with  The apparatus was  "Chlorothene" t e s t e d both  at vacuum and under pressure f o r leakage. A i r was  removed from the i n s i d e of the v e s s e l by a high-vacuum  pump and approximately  s i x t e e n pounds of r e f r i g e r a n t were charged  into  the v e s s e l which r e s u l t e d i n a pool of l i q u i d about 12 inches deep. The  s i g h t - g l a s s i n d i c a t e d the proper l i q u i d Heat was  lower end  level.  supplied by threes300-watt c a r t r i d g e heaters at the  of the heating rod.  Heat f l u x d e n s i t i e s were c o n t r o l l e d  by use of a V a r i a c and the power input was  i n d i c a t e d by a wattmeter  which provided a check on the c a l c u l a t e d heat f l u x values. As evaporation of the l i q u i d was the c o o l i n g e f f e c t of the condensing  t a k i n g place i n s i d e the v e s s e l , c o i l connected  to the  refrigera-  t i o n plant caused vapor to condense on the outer surface of the c o i l and drip down to the l i q u i d . c o i l was  The  cooling effect  of the  condensing  c o n t r o l l e d by the p o s i t i o n of the manually adjusted  expansion  valve at the c o i l i n l e t and the globe valve at the c o i l o u t l e t to obtain the d e s i r e d constant b o i l i n g temperature of the l i q u i d the v e s s e l .  inside  (a) Pig. 7.  (b)  Finish patterns of copper heating surface  (a) p a r a l l e l - l i n e pattern  (b) cross-line pattern  .(b)  (a)  Fig. 8 .  Photomicrographs of 400-A polished copper heating surfaces  (a) p a r a l l e l - l i n e pattern  (b) cross-line pattern  (magnification power: 160)  '92  27.  Temperatures were measured by thermocouples at various locations and recorded by the Philips recorder on a continuous  chart at a speed  of 300 mm per hour. Steady-state boiling at any desired temperature and heat flux density  was attained i n about 30 minutes by adjusting the Variae  and the valves at the i n l e t and outlet of the condensing c o i l . condition was  This  clearly defined when steady readings from the thermo-  couples were indicated on the chart of the Philips recorder.  When  steady-state boiling was attained, a l l instrument readings such as wattmeter, barometer, manometer, pressure gauge, ice bath thermometer, and room temperature thermometer were read and After the completion  recorded.  of each series of test-runs, the refriger-  ant was removed from the vessel and the apparatus was  disassembled.  The above-mentioned steps were repeated after the heating surface was re-polished to a new desired f i n i s h pattern.  V.  CALCULATIONS  The surface temperature of the heating surface was determined by extrapolation from temperatures measured at two or more points below the heating surface along the longitudinal axis of the v e r t i c a l 2-inch diameter 12-inch long copper rod.  No correction was made f o r  the f i n effect of the embedded thermocouple wires [9, 17] since the small effect was believed to be less than the accuracy of the instrument readings. The thermal conductivity of the copper heating rod was assumed to be that of pure copper.  By using the calculated cross-sectional  area of the rod and the distance between any two of the four thermocouples, the heat flux could be calculated with good precision and apparently good accuracy.  In calculating the heat flux density,  the .variation of the thermal conductivity of copper with temperature was allowed f o r . The recorded thermocouple millivolt readings were converted to temperature by standard conversion tables.  The recorded data  (T., T., T T_, T and w) and the calculated data (surface tempera1 2 4- 5 • o jt  ture " " » surface-to-liquid temperature difference "AT", unit heat T  w  flux "Q/A", and heat flux density by wattmeter "Q ") are l i s t e d i n W  Appendix I I . The f i r s t column heading "TR-N" of Appendix II denotes the test-run numbers. bols".  Other headings are explained i n "List of Sym-  Sample calculations are shown i n Appendix I.  Measurements taken of the boiling temperature by thermocouple TC-6 were checked against temperature values obtained by means of the mercury manometer (MM) and barometer. than half a degree (see Appendix i ) .  The differences were less  Thus the thermocouple values  29.  were believed to be entirely r e l i a b l e and were used without any correction.  DISCUSSION OP PROCEDURE  To insure the consistency of homogeneous physical properties of the dichlorodifluoromethane (CC1 F ), Genetron-12 of A l l i e d Chemical 2  2  Canada Ltd. was used i n a l l test-runs throughout the course of experimentation. To study the effects of the surface texture on heat transfer coefficient, tests were conducted separately by f i n i s h i n g the heating surface i n two different patterns (Fig. 7) while the geometric arrangement of the apparatus and testing conditions remained unchanged. Photomicrographs of the surface are shown i n Fig. 8 . A 12-inch depth of l i q u i d refrigerant over the heating surface seemed to be deep enough to avoid any effect of the l i q u i d level on the heat transfer coefficient at nucleate boiling. co-workers  Yamagata and  [19] have conducted boiling heat transfer experiments  at several depths  of liquid level and showed that the heat trans-  fer coefficients remain f a i r l y constant over the range of liquid l e v e l from 40 to. 60  mm.  To prevent possible hysteresis effects as described by Corty and Foust [l3], the test sequence of each run was from higher to lower heat flux densities.  A few test-runs from lower to higher  heat flux densities were also conducted. To mimimize variations of the heat transfer coefficient due to ageing of the heating surface, series of test-runs were completed i n the minimum possible time after each polishing of the heating surface. Copper- constantan thermocouple wires (Gauge 26 B & S) were used to measure the temperature at various locations and proper precau-  31.  tions were taken to avoid inaccurate readings.  The thermocouples  responded sensitively to any change i n either heat input or test vessel pressure. A l l instruments and equipment were carefully inspected, aligned, and calibrated before and during each series of test-runs. The experimental results were accurate enough for analytic purposes.  A high precision galvanometer and potentiometer were used  to check the accuracy of temperature  measurement by the Philips  recorder of each thermocouple. A l l experimental data i n Appendix II were recorded by the Philips recorder except the second set of data i n Test-run Nos. 4 5 and 46 which were measured by using a Cambridge vernier potentiometer and a Scalamp galvanometer as a check.  A comparison of pairs  of values i n Test-run Nos. 45 and 46 show that apparently the Philips recorder gave quite r e l i a b l e and accurate readings. A sensitive microphone was used to try to detect the instant of inception of boiling without success.  VII.  ANALYSIS OP TEST RESULTS  32. The results of this investigation are summarized i n Pig. 9 i n which the heat transfer coefficient "h" i s plotted as a function of the unit heat flux "Q/A"  and i n Pigs. 10, 11, 12, and 13 i n which  the heat transfer coefficient i s plotted as a function of the temperature difference  "AT".  In Pig. 9, the results of the investigation are compared with those given i n recent papers by Stephan [3] and Purse [ l 5 ] . In the nucleate boiling region, the relationship between heat transfer coefficient and temperature approximated  difference can usually be  by the empirical relation [ l , 12] . h = const. (Tw - T s )  m  (8)  with m from 1 to 3; the constant depends on the thermodynamic properties liquid  of the vapor and of the liquid and also on the s o l i d -  combination.  Comparison to Stephan's and Purse's results for boiling Freon12, shown i n Pig. 9 revealed that a l l data obtained i n the present investigation gave curves which, were considerably steeper than those of these investigators.  It was found, after correlating  the experimental data by Equation ( 8 ) , that Stephan's and Purse's results show a value of "m"  of 2.6 and 6.54  respectively and the  present case yields a very much larger value of 24 for  "m".  Recent experimental results, as mentioned i n Zuber's papers [l, 5] , show that both the value of the constant and of the exponent i n Equation ( 8 ) depend on the characteristics of the The value of the exponent "m"  surface.  at a constant pressure and for the  Stephan's data Purse's data Author's data Numbers inside brackets indicate the test-run numbers. 2  3  4  5  6 7  8 9 1x10'  2 2  Pig. 9.  Unit heat flux " o y A " , B t u / h r - P t Comparison between Stephan's, Purse's, and author's experimental results  10  12  14 Pig. 10.  16  18. 20 o 22 24 26 AT = (Tw - Ts), P Boiling curve of high-low-high heat flux densities  28  30  32  Test-run Nos.  35  Surface was  15 - 20) Surface was refinished after 21 - 24) each series of test-runs.  finished i n p a r a l l e l - l i n e  Thin layer of o i l was  30  found on heating  pattern. surface.  Numbers inside symbols indicate test-run numbers.  Pig. 11  AT = (Tw - Ts), °P Boiling curve of Genetron-12 at 2 5 ° & 0°P saturation temperatures (parallel-line f i n i s h pattern) p  10  12  14 Pig. 12  16  18 20 22 24 26 28 30 AT = (Tw - Ts), F o Boiling curve of Genetron-12 at 25 P & 0 P saturation temperatures (cross-line f i n i s h pattern) 0  0  32  Fig.  13.  AT = (Tw - Ts), F Effects o f heat transfer coefficient by thin layer of o i l on heating surface  UJ  38. same s o l i d - l i q u i d combination can be varied from 3 to 24 by changing the surface roughness. Examination of Pigs. 10 to 13, shows that a l l boiling curves (h vs. AT) plotted from the present experimental data revealed an " S " shape which deviates i n a pronounced manner from the general form (Fig. l ) assumed f o r a boiling curve, especially at lower saturation temperature.  None of Stephan's or Purse's boiling curves  was found i n "S'' shape. A comparison of the experimental parameters of Stephan Q3]]» Purse [l5] and the author i s shown i n Table I I I . Disregarding the surface f i n i s h pattern, a l l conditions or values of the parameters are nearly the same except f o r the considerable difference i n surface roughness. Table I I I . Comparison of Experimental Parameters o Testing Under Sat. Temp. 0 F & Investigator  Heating Surface  Refrigerant  Stephan  130 mm. Preon-12 dia., horizontal copper surface  Furse  2 in. Preon-12 dia., horizontal copper surface  Author  2 in. Freon-12 dia., horizontal copper surface 1  o 25 F  Finish " Surface Roughness Pattern (microinches r.m.s.) Unknown  40  (|p  8-15 (radial) 18-27 (circumferential)  39. Prom Pig. 9, i t i s noted that the finer surface f i n i s h yields the steeper boiling curve.  When this steeper curve was converted  and replotted as a function of "h" and temperature difference, an "S" shaped boiling curve was obtained.  Therefore, i t may be conclu-  ded that an "S" shaped boiling curve i s attributable to certain specific nucleating characteristics which occur on surface with such a f i n e r degree of f i n i s h . Zuber [ l ] confirmed that similar results of an "S" shaped b o i l ing curve were obtained previously by Corty and Poust Long [18] .  [JL3] , and  Zuber [ l ] , Rohsenow [6], Westwater [2], and others a l l  agreed that a generalized correlation cannot be expected unless the correlation takes into account the nucleating characteristics of the heating surface and of the bubble population. Since a l l the present correlations f o r nucleate boiling were evaluated from a normal-shape (Fig. l ) boiling curve, the present data cannot be correlated by any of the existing empirical equations suggested by previous investigators [6, 14, 16, etc.] . Unfortunately, at present, there i s no correlation which can predict a boiling curve i n "S" shape.  Further investigation i n the  nucleating characteristics of the heating surface and s o l i d - l i q u i d combination may give an empirical equation of the type h. = C  (AT) + C m  2  (AT)"  (9)  which might predict the true shape of a boiling curve i n the nucleate boiling region. Corty  et a l  [ l ^ ] obtained an "S" shape boiling curve when heat  40. was  supplied  effect were  from  to hysteresis.  conducted  densities, shape flux  heat  cient  finish  than that  Identical separate  pattern within A comparison  ted  o b t a i n e d were v i r t u a l l y  the range of P i g s .  of the p a r a l l e l - l i n e .  boiling  of e x p e r i m e n t s 10 and 11 shows  The  independent performed, t h a t the  b e t t e r heat t r a n s f e r  This  coeffi-  i s p r o b a b l y due t o t h e  p a t t e r n had more n u c l e a t i o n  c u r v e s were  only approximately  of the same s u r f a c e a f t e r  t o the f a c t  surface  rates  surface.  either  were n o t o b s e r v e d .  flux  cavities  t h a n the  that  different  were f o u n d  obtained f o r  each r e f i n i s h i n g .  This i s  t h i c k n e s s e s of l i g h t  o i l con-  on t h e h e a t i n g s u r f a c e a f t e r  each  of t e s t - r u n s .  A clean better  test-runs  10, 11 and 12o  p a t t e r n had a s l i g h t l y  taminated with d i r t series  a few  pattern.  tests  attributed  in boiling  coefficients  the c r o s s - l i n e  parallel-line  They a t t r i b u t e d t h e  c u r v e f o r b o t h i n c r e a s i n g and d e c r e a s i n g heat  transfer  11 and 1 2 ) .  that  effects  the same as shown i n P i g s .  of s u r f a c e f i n i s h  cross-line  flux.  I n the p r e s e n t i n v e s t i g a t i o n ,  and h y s t e r e s i s  remains  (Pigs.  t o h i g h e r heat  b o t h f r o m h i g h e r t o l o w e r and l o w e r t o h i g h e r h e a t  of t h e b o i l i n g  The  fact  lower  or a s u r f a c e  of h e a t  transfer  The p r e s e n c e  impurities  layer  of o i l gave  (see P i g . 13) t h a n a h e a v i l y  slightly  contamina-  of o i l i n t h e a p p a r a t u s was p r o b a b l y due t o  i n the r e f r i g e r a n t  a p p a r a t u s and i t s p i p i n g "Pool-Boiling  with a t h i n  system  or t h e r e s i d u a l  from Purse's  lubricant  i n the  p r e v i o u s experiment i n  of M i x t u r e s of O i l and R e f r i g e r a n t "  [15J.  The was  slope of the boiling curve at the nucleate boiling region  found to decrease gradually i n each consecutive series of test-  runs (Pigs. 11 and 12).  This phenomenon indicated  rate of boiling heat transfer was surface and  due  that the reduced  to the ageing effect of the  the fouling effect of the solids deposited on the sur-  face during the time of  use.  VIII.  CONCLUSIONS  42. For boiling of Freon-12 on a copper surface as described, c l a s s i cal correlations are inadequate £8 ] . No great influence of pattern of f i n i s h upon heat transfer coefficient has been observed provided that the overall roughness i s the same. Slight influence of surface contamination upon heat transfer coefficient was noted during the course of the investigation. The experimental results of the present and few other i n v e s t i gations [l3, 18] have concluded that the negative-slope or "S" shape i s another possible form of a boiling curve which may be due to the unpredictable nucleating characteristics of a heating surface and of bubble population. Therefore, further investigations, both theor e t i c a l and experimental, i n boiling heat transfer are required to be conducted i n order to obtain a complete knowledge of bubble mechanics.  IX.  SUGGESTIONS FOR MODIFICATION OF APPARATUS  43. A s i g h t window on the main body  of t h e v e s s e l n e a r t h e  surface  i s deemed i n d i s p e n s a b l e i n o b s e r v i n g  and  flow  the  pattern  of the  boiling  of t h e h o r i z o n t a l s u r f a c e d u r i n g used t o t a k e  photographic  mechanism and  liquid  the  boiling  i n the  pictures f o r studying  phenomena  immediate  experimentation.  heating  vicinity  I t would a l s o  the  bubble  be  separation  f o r s e a r c h i n g a r e p r e s e n t a t i v e model of b o i l i n g  heat  transfer. The  unsteady  generated cult  by  the  three  to maintain  recommended the  power-line  that a  A fine-control of t h e  constant  and  heat  the v a r i a b l e  condensing  coil.  valve  valve.  different  o b t a i n the liquid,  liquid  apparatus. installed  It i s between  transformer. i s needed  should  be  t o c o n t r o l the  installed  I t t o o k a much l o n g e r  present  of t h e b o i l i n g  flux  exact  input.  s a t u r a t i o n temperature  to  r e g u l a t o r be  v a r i a b l e transformer  desired  In order  of h e a t  w h i c h i n t u r n made i t d i f f i -  c o n d i t i o n i n the  voltage  A f i n e - c o n t r o l expansion of the  caused a f l u c t u a t i o n  cartridge heaters  a steady-state  power s o u r c e  value  voltage  inside  pattern  inlet  time  to a t t a i n  a  the v e s s e l by  adjusting  the  of the  temperature  more t h e r m o c o u p l e s s h o u l d  l e v e l s above the  at the  heating  be  surface.  distribution  installed  at  X.  APPENDICES  44.  Appendix I.  SAMPLE CALCULATION'S  d  =  diameter of heating surface = 1 . 9 6 9 5 i n . = 0.164 f t .  A  =  area of heating surface = 0.02115 sq. f t .  x^ =  distance to thermocouple 1 from surface = 0 . 2 5 3 i n .  x  distance to thermocouple 5 from surface = 3.035 i n .  5  =  Data f o r Test-run No. 15.001:Barometer reading  =  29.82 i n . Hg.  Barometer calibration error  =  -0.08 i n . Hg.  Heat input to apparatus by wattmeter Room temperature  =  Temperature  1  (°P)  403 watts.  77.3°P.  Thermocouple No. Millivolts  =  2  4  .360  -  48.65  -  5  . 1.066 80.4  6  7  1.845  -.149  .996  114.0  25.0  77.3  Calculation for Test-run No. 15.001:x  1 ~  w  X  AT k  = =  Q/A  T  — 5 "  - T, o  w  =  V (T 5  =  x 5  -  =  (Q/A)X(A)  h  =  (Q/A)/AT =  42.72 °P.  1  = 17.72 °P.  T ) Y =  K  Q  w  5  225 - 0. 04 (T ) = 221.8  (  Q  (T_ - T ) l  X  x x  62472  Btu/hr-ft-°P.  Btu/hr-ft  2  )  = =  3.41 x 403  1321 Btu/hr. 3526 -  Btu/hr-ft  1374 Btu/hr.  -  P.  45. P/Q  percentage difference between Q and  =  Q - Q  w  =  Q> w  3.  Q  w Liquid temperature determined from vessel pressure: (Pressure i n vessel above liquid) = (Manometer reading) i  (Manometer temp, correction) + (Mercury barometer  reading) - (Barometer correction) P  v  = (50.15 - 0.208 + 29.82 - 0.08) = 79.67 i n . Hg. abs. 0  Temperature at l i q u i d surface = 24.70 the  /  P. (corresponding to  above vessel temperature)  Difference between pressures at l i q u i d surface and at thermocouple TC-6 = 6 i n . Genetron-12 at 25 = 0.3 p s i .  0  P. o  Temperature difference corresponding to above Temperature at thermocouple 6 Mote:  = 24.7 + 0.4  =  0.4 P.  = 25.1  Thermocouple TC-3 was damaged and not connected.  °P.  Appendix  T—R  NR  Tl  T2  T4  80.40 71.40 56.00 49.50 45.20 40.10 64.90 5 6 . 70 42.60 35.80 26.80 "T8T2TT 80.50 71.50 56.60 48.70 44.70  -207T03520.037 20.038 20.039 20.040 20.041  *  48.95 17. 15 21.60 22.85 25.70 29i25 31.75~ 30.00 28.05 26.35 23.30 I8i 70  Zero values  66.40 57.50 4 3 . 70 35.80 26.35 18.25 38.60 42.30 4 7 . 10 55.00 70.30 /y.60 17.35 23.50 27.35 36.60 52.30 63.40 53.30 39.00 31.30 25.00 19.30  II.  TEST  CP  <B?BIGEHAST  T6  T5  114.00 9 6 . 80 68.55 55.90 48.60 4 1 . 5U 9 8 . 10 82. 10 54. 75 41.60 29.75 19.50 114.45 96.95 6 9 . 15 54. 70 47.90 -42.95 100.00 82.80 55.35 41.80 29.00 18.80 39.90 45.40 53.20 67.50 96.85 114.U5 18.45 26.40 33.60 48.90 77.70 97.80 79.30 51.45 37.65 27.60 20.30  i n column "T2" i n d i c a t e  DATA  W  25.00 25.35 25.00 25.40 25.40 2 5 . 5U - 0 . 15 -0.05 0.35 0.50 0 . 10 —0.25 2 5 . 15 2 5 . 15 25.35 25.00 24.95 25.45 0.50 0.50 0.40 0. 0.30 —0.50 25.55 25.50 25.65 25.60 25.20 25.25 0 . 10 0.15 0. 0. -0.20 -0.20 -0.35 0. 0. 0. - 0 . 10  readings  403.00 303.00 146.00 77.00 40.40 20.50 398.00 303.00 149.00 74.50 39.50 20.2U 400.00 306.00 151.00 74. 50 40.40 24.70" 403.00 301.00 150.00 77.00 40.20 2 0 . 30 19.80 3 8 . 70 75.50 149.00 303.00 398.00 19. 70 40.50 74.50 149.00 296.00 402.UU 300.00 151.00 76.00 40.50 20.50  were  DICHL0H0DIPLU0R0M3THAHE*(GENET8CN-12)  TW  DEL  4 2 . 72 43.24 42.86 4 3 . 36 42.49 39. 32 28.62 29.52 2 9 . 72 29.93 24.35 17.97 4 3 . 33 43.28 4 3 . 30 4 2 . 70 41.90 39. 79 29.75 3 0 . 17 3 0 . 75 29.64 24.04 17.60 37.66 39.62 41.09 42.41 42.53 43.04 1 7.03 2 1 . 16 21.87 23.59 24.85 2 5 . 75 25.52 25.93 25.32 22.91 18.55  17.72 17.89 17.86 17.96 17.09 13.82" 28. 77 29.57 29.37 29.43 24.25 Ll. U 18. 18 18. 13 17.95 17.70 16.95 14. 34 29.25 29.67 30.35 29.64 23.74 17. 10 12.11 14. 12 15.44 16.81 17. 33 17.79 16.93 21.01 21.87 23.59 25.05 25.y5 25.87 25.93 2 5 . 32 22.91 18.65  unobtainable.  T  Q/A 62472. 47014. 22612. 11055. 5387. —1926. 61065. 46274. 220B9. 10311. 4778. —1353. 62328. 47109. 22754. 10576. 5292. —2792. 61720. 46316. 21700. 10745. 4392. —1063. 1975. 5101. 10675. 22088. 47694. 62242. 1257. 4636. 10375. 22354. 46551. -"573757 47359. 22537. 10898. 4152. 1546.  Q 1321. 994. 47B. 234. 114. — 4 - n 1292. 979. 467. 21B. 101. —zr. 1318. 996. 481 . 224. 112. 577 1 305. 980. 459. 227. 93. T7T. 42. 138. 226. 467. 1009. 131b. 2 7. 98. 219. 473. 985. 1340. 1002. 477. 230. 88. 33.  3526. 2628. 1266. 615. 315.  1797  2123. 1555. 752. 353. 197. r57 3423. 2593. 1263. 59 7. 312. —PT57 2113. 1551. 715. 363. 185.  —rz~. 163. 361. 691 . 1314. 2752. 3499. 74. 221 . 474. 947. 1358. 244U. 1333. 859. 433. 181. 83.  1374. 1333. 498. 263. 138. 7TT7 1357. 1033. 538. 254. 135. 6"97 1364. 1343. 515. 254. 138. :—BTfr  1374. 1 326. 511. 263. 137. 6~97 68. 132. 257. 508. 1333. 1357. 67. 138. 254. 538. 1009. 1371. 1023. 515. 259. 138. 70.  3.85 3.76 3.94 13.95 17.29 4 1 . Ii '•>. 64 5.28 3.35 14.15 2• '. . 9 8 ' 5a.45 3.36 4.51 6.54 11.95 13.76 29.99 5.01 4. 56 13.27 13.45 32.24 67.51 33.15 13.24 12.31 3.05 2.37 —3.U0 63.43 29.01 13.63 5.95 2.45 —2.28 2.09 '.43 11.05 36.42 5 3.21 _  47-  h- rg in O A r— O m *  * *  ^  ro oo -o o co « (M ro —' -J^•O / I 4 •* N f- A m ro %o r N a? o t\j H in ro co co rft O IA N ^ oi m m w O in (M f l A «fl  *4  o i n 4 CO CO CO 4  ^ m m N M u>  -4  f> —• so -4- O in N - co o rt oo fn 4 in o fn 4 o ~^ r\j o • ^ i*l X 4 13 rt in fl o -o o CM r- co rf*. —« m co co0 O I "O O W <*> CO «0 ^ C* r-> «0 rt ro *fl fl fl m CM CM in O fl rt m ro o m CM — o r\ i* o m N  •4-  1  -4-  fl (ft  o CM rr- <D O U"\ M NL A in in co ao co cy m flCM o•J- O r>- o -4- CT> rt ^0 -O f*-rt-4" i O CM fl CM fl ?• -O CO H 4 -J O O o co in a O * C O £C O mcocvj N s c O m N 4 > 00 *o co o CM o N fl O r- C» fl r- 4 m f> o N rt fl r> >o r~ A J _t u*\ rt ^- rt in CM rt rO ^ O rt ru sO r- fl rt rt ro m CM —* rt fl' >t - I •O N H CO CN s0 f\f rt -J" —' v-( ^ r\i ro rn rsi -H (N A CM rt rt ro CM rt (M rt m CM rt h- A —I O ro CM rt  «4  ^4  -4"  O O co LA  1  1  -J  4 >  CO CM  rt  CO CM O 4 CM CM rt CM  C m  -4-  ( N 5 " <D O -O in CM -4- o t> in P- *0 O fl t\j —' ro C* OCT*flrt o fl CM o c* *~fl as sf sir\j p- r- co in c r i n co m N r- r» m —t to N (VJ « o> «0 fM —* so <r o o CM —< CM o oo ^ H O ^ O ^ o ooo K N o in N m «ort%o fl r » rt o co rt o in m fl o in o (« C * N H ro oo A A fl 0** •4" fM —I fl «0 CM fl 0"* -J" CM rt o>flrt fl o ^ CM — •4fl>oflflO (M  (\J  •4-  « i in 0 iflin r- co A cy —• rvj Ifl IT ff 0* N ffl co in m *o cr co < -* >o CM coO N (M in H rt •O IM r* O N » rt CO I A O xf >0 N -O •J- CO sT CD rsi CM —I sO ^ O -J- IM ^ CT- rt t\j rt CM 43 .fl sfr CN rt  rt-,44*-  1  H  Mo  1  o <o ^  co oo c* r- r* <  ro CM in o O O l f t N * vfr CO rt CM  fl rA rg -fl  -O r*- -fl fl CO o r- CM •J- CO rt « -4 LA CNCO r- (M o in CM "4" IM rt  -4"4"  CM O CO O CO CT O O COco fl O 0^ fj* N IT 1in N CO «o «o m fl o o rt -fl O rt rtm <o ^o <o ^ m O • O C M 0 4 N O rt -4- CM rt CM  -4  4"  00 O CJ* O* CO CO  o O O «J- ITi O —< N o in o o o o  rt  <M  ^4 -4- 4-  A  O  O O CM 4-  .4-  o co fl r-J"  c  -4mrt  fl o co ^ fl CM O fM rt  1  in fl fl CO ^0 s0 o rt CM m fl in O sO in ro in o o m CM CM O O rt rt fl o  co ao f*- m c  c o in o o m m O 4 O 4 in o rt CM 4 o o rg in in O O in N 4 M N m o o O fl *4 ro rt  O  rt  o o o o o o  O O O O O O  O O O O © CO  a> co o mhO CM CO CO 0> CM h- rt co m CM CM O in CM CM -0 CM -4" CM >-*  C7*  CO O fl 0* -T O m a* o * cr o o - 4rt - -4-rt 4flo»r fl -4-4 fl CM  •4-  1  CM  \ O O O O O  o o r- o O in  4- -rm^ j r ^ i o o c ^ O r t r s j r o ^ i n ^ r ^ c o ^ O r t C M f l s r i n ^ f ^ c o c ^ 4 in -O M D CT O rt CM fl •? •4- -4 " 0^ c^ -4" ^ l - r 4 in in in uvin m in in m in *o o o o « ^ o -A -o s r*-if*- f- r - r» f** r*-|f- r- co co oo co CO CO CO CO CO CO QA CT* o o o o o o;a o o o o o;o o o o o o o o a o o o o o o o o q>;o o o o o OJO o o o o o o o o o o o o o o o o CN A  rt ^ t | r t —i (N (M'CM (M CM CM <M OJ (M fl fl fl fl fljfl fl fl fl fl •f\'f •* >f sf 4* -4 CM CM CM CMCM CM | CM CM CM fM <M (MiCM CM CM CM CM CMJCM CM CM CM CM <M i CM C N C M C M f M C M f M C M C M C N C M C M 1  „.„A..  fl  Appendix I I .  T-R NR  TI  26.095 26.096 26.097 26.098 26.099  32.25 30.50 28.75 27.25 19.05  T2 41.05 35.15 30.30 28.00 -0.  TEST DATA CP REFRIGERANT DIC HLOR ODIP LU OR OMETHAHE (GEHETROH-12) -  TA  T5  T6  M  55.00 41.50 34. 10 29.95 20.40  81.15 53.70 39.90 33.90 21.80  0.05 0.60 0.35 0.45 0.40  303.00 150.00 76.00 50.50 25.30  TV* 27.81 28.39 27.74 26.65 18.80  (Continued)  DEL T  0/A  0  H  CH  P/U  27.76 27.79 27. 39 26.20 18.40  46961. 22334. 10748. 6415. 2657.  993. 472. 227. 136. 56.  16^2. 804. 392. 245. 144.  1033. 511. 259. 172. 86.  3.87 7.65 12.29 21.21 34.85  -<  o  *- m -o  CO (\J —I CO «0 CO • f o m ^ o rt •j- —< m r - co vj- co ao r*- —• o l A N CO <C >J rt *o rt rt o i n O N -H rt o  rt i n O 3* O •4" rt CO -O *d" "4" •o rg o m r*- co N ("^ H IA >0 tD f i o in N m o LO <\i  iTi -O I N cr N i n i n co co O O — i O I - I - *t rt i n -o rt o >C O n ifi fl> *0 eg -O rt - « rvi *o I - rt f\i —• co m «o co >o © o rt rg - « in m rt CM O O  s  o  S  s  rt  sj- m —t  o co K ffl a - >f  hr\j N  cy  n  f- o m o o o co ^3 (Nl  IT H  ^ c\i ^ © r» rCD •O ^ N S m i-t rg O -O •O -4" CM —t  rt  m m 0* •o O ^ rg -O  o  «  N  ^  H  ^  N  in CO r - in O ^  rsO m rg rg  i n o co O CM f*- (M i n co ^ a-->0 rt j —< -<  o o c* m — Psi rt —t %o a* i n h IA O o o r - i n rg o o i n i * - «r r\j O O IA M A -j- rt -M •j- rt -< %T rt -4  o  rt  ^ rt  M >o m c rt m m m rt O co cj* i0 oo i n sj" •4- o o —' rt f\i o rt w o rsi ^ N >o N rt eg — i -J- o CNJ rg o r rg CM —<  CM —<  CO CO 33 CO N  o o o o o  -i  N  O  1  O  r - a* in i n «o co - t co p -  m  m «o rt rt i n go eg r\j i n o m c\j co rg rt m rt «t O O M M * <0 M O M A o N <t o -< rt 0" rt \0 rt rt CT rt O tM <-t  m M -o rt -o m o *o I N  O -i O vT rsi  i n co CM (M -o m -< rt  m  m  co  IA S  i n <• m -d- - H  -O in rt o rt  O rt O iv «o  rt m I-< «0 s  <T> ~* H  O (J o f— rt co M O* rt co r- o C M A f\J m -1" M 1  N o- m  o  H  rt yi rt m o *f  — ' r\j >J- r- r\| o r\j r g g3 rt  N  a- of*-so *  «0 -J- (M  o  r— r— rt in o o o rt >o  - i O sO rt ( M O m M  rt o> H M O  4"  IT pg o m vj- co c M o o o o t J ^ M A (N xj" -J" t\l - «  O  IA  o o o o o  o  1  M  O  IA  ^  •d" rt  O  O  O  -  CM O  O  O  O  O  O  O  sj- rt r g >r >o o*>  I  rg CM -j- N T  rt  )  CM  rt rt >f  Appendix I I . TEST DATA OP REFRIGERANT DICHLORODIFLUOROMETHANE (GENETRON-12) - (Continued)  T-R NR *  32-139 32.140 32.141 32.142 32.143 32.144 33.145 33.146 33.147 33.148 33.149 33.150 34.151 34.152 34.153 34.154 34.155 34.156 35.157 35.158 35.159 35.160 35.161 35.162  Tl 47.15 45.80 44.15 42.60 42.15 39.65 29.85 28i85 27.10 25.70 25.00 19.75 46.95 46.00 44.25 42.80 42.00 40.00 29.60 28.40 26.70 25.65 24.85 19.50  TZ  T4  58.90 54.51 48.00 44.50 43.30 39.90 40.65 36.60 30.70 27.20 25.50 -0. 58.30 54.50 48.35 44.70 43.15 40.40 40.20 36.35 30.35 27.30 25.25 19.80  78.35 69.45 55.00 47.65 45.35 40.90 59.80 50.80 36.90 30.30 27.50 21.00 77.65 69.00 55.30 47.85 45.20 41.60 59.45 50.65 36.80 30.35 27.60 20.70  T5 113.00 95.85 67.45 53.85 49.25 42.70 94.15 76.55 49.00 35.65 31.40 23.30 111.65 94.90 67.90 53.65 49.15 43.30 93.65 76.50 48.85 35.70 31.40 22.75  T6 25.30 25.30 25.30 25.30 25.35 25.35 0.35 0.45 0.35 0.35 0.35 0.35 25.35 25.35 25.35 25.35 25.20 25.25 0T35 0.35 0.35 0.35 0.35 0.40  H 410.00 308.00 151.00 75.50 50.20 25.50 403.00 297.00 152.00 75.50 49.20 29.60 403.00 303.00 151.00 75.00 50.30 26.00 403.00 300.00 149.00 74.50 49.50 29.50  TW  DEL T  Q/A  Q  H  QH  P/Q  41.17 41.26 42.03 41.58 41.51 39.37 24.01 24.52 25.11 24.80 24.42 19.43 41.08 41.56 42.10 41.81 41.35 39.70 23.78 24.03 24.69 24.74 24.26 19.20  15.87 15.96 16.73 16.28 16.16 14.02 23.66 24.07 24.76 24.45 24.07 19.08 15.73 16.21 16.75 16.46 16.15 14.45 23.43 23.68 24.34 24.39 23.91 18.80  62974. 47941. 22376. 10818. 6830. 2936. 61697. 45843. 21100. 9598. 6177. 3430. 61882. 46843. 22711. 10433. 6879. 3177. 61461. 46229. 21341. 9694. 6321. 3140.  1332. 1014. 473. 229. 144. 62. 1305. 970. 446. 203. 131. 73. 1309. 991. 480. 221. 145. 67. 1300. 978. 451. 205. 134. 66.  3968. 3005. 1337. 665. 423. 209. 2607. 1905. 852. 393. 257. 180. 3935. 2890. 1356. 634. 426. 220. 2623. 1952. 877. 398. 264. 167.  1398. 1050. 515. 257. 171. 87. 1374. 1013. 518. 257. 168. 101. 1374. 1033. 515. 256. 172. 89. 1374. 1023. 508. 254. 169. 101.  477T 3.46 8.09 11.13 15.61 28.58 5.05 4.26 13.90 21.15 22.14 28. 13 4.76 4.11 6.71 13.72 15.18 24.22 5.41 4.42 11.16 19.29 20.80 33.97  Appendix I I .  T-R NR 36. 163 36.164 36.165 36.166 36.1b7 36 . 168 37. 169 37.170 37.171 37. 172 37.173 37.174 38.175 38.176 38.177 38.178 38.179 3 8. 180 39.181 39.182 39.183 39.184 39.185 39. 186 39.188 39.189  Tl  T2  48.00" 59. 10 46.85 55.40 44.35 48.25 42.70 44.40 41.65 42.75 3 8.40 39.05 33.10 44.05 32.50 40.65 31.10 34.45 29.60 -0. 28.05 28.90 18.70 18.95 48^25" 59.70 47.05 55.40 44.35 48.35 42.60 44.65 42.10 43.25 IT. 60^ _r_0. 33.20 ~ 44.15 32.00 39.90 30.70 33.40 29.50 31.35 27.50 28.60 19.60 20. 15 37.30 50.80 35.25 47.50  TEST DATA C? HJ?RIGBRA.!T DICHLCRODIH'LUORCMETHANE (GENETRON-12)  T4  15  78.50 70.00 55.40 47.80 45.00 40.00 63.40 55.20 41.30 34.60 30.85 19.60 78.90 70.00 55.40 48.00 45.30 39. 10 63.00 54.35 40.10 33.70 30.30 20.90 74.40 69.70  112.60 96.05 67.95 53.90 48.95 41.80 97.70 80.65 53.30 40.45 34.40 21. 15 113.30 95.75 67.90 53.90 49.25 41.00 96.65 80.10 52.10 39.35 33.70 22.60 116.40 108.40  T6  W  25.30.403.00 25.30 306.00 25.30 150.00 25.30 75.50 25.30 49.60 25.30 24.20 0. 35 405.00 0.45 302.00 0.30 149.80 0.35 75.50 0.30 51.20 0. 30 24.00 25.30 405.00 25.40 303.00 25.20 151.00 25.30 74.50 25.30 49.50 25.30 25.00 0.45 404.00 0.35 303.00 0.35 149.00 0.35 74.50 0.40 50.50 0.40 25.00 0.45 500.00 0.35 450.00  TW 42. 13 42.38 42.21 41.68 40.99 38.09 27.23 28.13 29.08 28.61 27.47 18.48 42.34 42.63 42.21 41.57 41.45 37.29 27.44 27.63 28.76 28.61 26.94 19.33 30.12 28.61  DEL T 16.83 17.08 16.91 16.38 15.69 12.79 26.88 27.68 28.78 28.26 27.17 18. 18 17.04 17.23 17.01 16.27 16.15 11.99 26.99 27.28 28.41 28.26 26.54 18.93 29.67 28.26  O/i  0  -  (Continued)  H  61777. 1307. ' 3670. 47122. 997. 2758. 22663. 479. 1340. 10770. 228. 657. 7023. 149. 448. 3274. 69. 256. 61945. . 1310. 2304. 46239. 978. 1671. 21372. 452. 742. 10458. 221. 370. 612S. 130. 225. 2368. 50. 130. 62202. 1316. 3650. 46643. 986. 2707. 22614. 478. 1329. 10866. 230. 668. 6878. 145. 426. 3274. 69. 27 3. 60846. 1287. 2255. 46198. 977. 1693. 20606. 436. 725. 9496. 201. 336. 59B1. 126. 225. 2899. 61. 153 . 75699. 1601. 2552. 70064. 1482. 2479.  Uirf WHT. 1043. 511." 257. 169. 83. 1381. 1030. 511. 257. 175. 82_. 1381. 1033. 515. 254. 169. 85. 1373. 1033. 508. 254. 172. 85. 1705. 1534.  P/U 4.92 4.49 6.29 11.53 12.18 16.09 5.14 5.04 11.51 It.09 25.81 38.81 4.74 4.52 7.11 9.54 13.81 18.76 6.59 5.43 14.22 20.95 26.55 28.09 b.10 3.43  Appendix I I .  T-R NR ^  j 1 | j  j !" i i i ! j j j I j I""'"' ! i I i  40.190 40.191 40.192 40.193 40.194 40.195 41.196 41.197 41.198 41.199 41.200 41.201 41.202 41.203 41.204 42.205 42.206 42.207 42.208 42.209 43.211 43.212 43.213 43.214 43.215 43.216 43.217 43.218 44.219 44.220 44.221 44.222 44.223 44.224 44.225 *Ai?2_6_ 45.226 " 45.227 45.227 45.228 45.228 45.229 45.229 45.230 45.230 45.231 45.231 45.23 2 457232 45.233 45.233 45.234 45.234  Tl  T2  T4  33.00 32.05 30.25 29.00 28.00 22.75 49.60 48.60 47.00 45.65 45.15 41.65 44.75 47.00 49.20 49.55 48.60 46.50 45.50 44.75 26.60 27.05 28.15 29.70 32.00 32.40 32.00 31.50 29.30 28.40 27.10 21.25 27.15. 28.40' 29.15 29.80 30.30 29.20 "28.85 27.65 27.40 26.40 25.90" 25.45 24.80 20.15 19.85 29.65 30.30 28.80 29.40 27.60 27.90  44.50 40.65 34.25 30.40 28.75 -0. 61.75 57.80 51.20 47.50 46.20 42. 15 45.70 52.55 60.90 61.60 57.45 50.70 47.25 45.80 27.20 28.40 31.90 38.80 42.60 44.65 43.05 39.35 34.60 31. 15 28.00 21.40 28.00 30.85 34.70 42.40 42.20 -0. -0. -0. -0. -0. -0. 26.30 -0. 20.35 -0. 42.90 -0. 39.10 -0. -0. -0.  62.75 54.55 40.90 33.70 30.85 23.65 80.40 71.70 57.90 50.90 48.40 43.35 47.90 61.60 79.45 81.45 72.20 57.65 50.60 48.00 29.40 31.55 38.30 53.00 61.40 66.10 62.20 53.35 43.60 35.50 29.80 22.20 29.85 35.25 43.85 61.50 61.50 53.00 53.00 38.20 38.20 31.00 31.00 28.10 28.10 21.30 21.30 61.70 61.70 53.40 53.40 39.30 39.30  TEST DATA OP REFRIGERANT DICHLORODIPLUOROMETHANE (GENETRON-12) - (Continued)  T5 97.25 80.35 53.35 39.50 34.60 25.15 115.30 98.10 70.60 57.05 52.40 45.10 51.75 78.70 114.00 117.25 98.40 70.25 56.75 51.80 33.00 37.40 50.45 78.40 95.20 104.80 96.65 79.20 60.65 43.40 33.70 24.10 33.80 43.20 60.30 96.60 96.50 79.00 78.30 50.85 50.80 36.20 36.40 31.40 31.40 23.15 23.10 96.35 95. 70 79.60 78.70 51.60 51.40  T6  U  TW  DEL T  Q/A  0  H  QM  5745 0.45 0.45 0.35 0.40 0.45 25.30 25.20 25.40 25.30 25.35 25.25 25.25 25.30 25.30 25.30 25.20 25.20 25.35 25.30 0.40 0.35 0.35 0.45 0.45 0.35 0.35 0.45 0.30 0.45 0.35 0.40 0.35 0.40 0.35 -0.30 0. 10 0.10 0.40 0.35 0.20 0. 15 -0. 10 0.65 0.35 0.40 0.10 -0.30 0. 30 -0.40 0.45 -0.10 0.45  405.00 303.00 151.00 76.00 50.80 25.20 403.00 302.00 149.00 76.00 51.00 24.80 50.80 200.00 400.00 408.00 305.00 147.00 75750 50.50 50.50 74.50 149.00 300.00 396.00 453.00 403.00 301.00 198.00 102.50 50.00 29.50 51.20 102.50 198.00 400.00 400.00 302.00 302.00 153.00 153.00 73.00 73.00 49.30 49.30 30.00 30.00 403.00 403.00 303.00 303.00 150.00 150.00  27.17 27.66 28.15 28.05 27.40 22.53 43.63 44. 11 44.86 44.61 44.49 41.55 44.11 44.12 43.32 43.40 44.08 44.34 44748 44.11 26.02 26.11 26.13 25.28 26.26 25.B3 26.13 27.17 26.45 27.04 26.50 20.99 26.55 27.06 26.32 23.73 24.29 24.68 24.36 25.54 25.28 25.51 24.95 24.91 24.20 19.88 19.55 23.59 24. 36 24.19 24.92 25.42 25.77  26.72 27.21 27.70 27.70 27.00 22.08 18.33 18.91 19.46 19.31 19.14 16.30 18.86 18.82 18.02 18.10 18.88 19. 14 19. 13 18.81 25.62 25.76 25.78 24.83 25.81 25.48 25.78 26.72 26.15 26.59 26.15 20.59 26.20 26.66 25.97 24.03 24. 19 24.5B 23.96 25.19 25.08 25.36 25.05 24.26 23.85 19.48 19.45 23.89 24.06 24.59 24.47 25.52 25.32  61616. 46388. 22240. 10122. 6366. 2318. 62807. 47395. 22652. 10956. 6971. 3128. 6731. 30407. 61957. 64707. 47677. 22797. 10812. 6779. 6174. 9981. 21480. 46786. 60624. 69390. 62006. 45822. 30168. 14456. 6367. 2753. 6415. 14263. 29975. 64076. 63501 . 47842. 47506. 22347. 22540. 9452. 10127. 5742. 6369. 2898. 3140. 6397S. 62731. 48800. 47359. 23113. 22632.  1303. 981. 470. 214. 135. 49. 1328. 1002. 479. 232. 147. 66. 142. 643. 1310. 1369. 1008. 482. 2297 143. 131. 211. 454. 990. 1282. 1468. 1311. 969. 638. 306. 135. 58. 136. 302. 634. 1355. 1343. 1012. 1005. 473. 477. 200. 214. 121. 135. 61. 66. 1 353. 132 7. 1032. 1002. 489. 479.  2306. 1705. 803. 365. 236. 105. 3426. 2507. 1164. 567. 364. 192. 357. 1616. 3439. 3574. 2526. 1191. 5657 360. 241. 387. 833. 1384. 2349. 2724. 2405. 1715. 1154. 544. 243. 134. 245. 535. 1154. 2666. 2625. 1947. 1983. 887. 399. 373 . 404. 2il. 267. 149. Ibl. 2673. 2607. 1985. 1935. 906. 894.  1381. 1033. 515. 259. 173. 86. 1374. 1030. 508. 259. 174. 85. 173. 682. 1364. 1391. 1040. 501. 25~77 172. 172. 254. 508. 1023. 135U. 1545. 1374. 1026. 675. 350. 170. 101. 175. 350. 675. 1364. 1364. 1030. 1030. 522. 522. 249. 24'j. 163. 163. 102. 102. 1 374. 1374. 1033. 1033. 511. 511.  P/O 5764" 5.04 8.65 17.39 22.28 42.95 3.34 2.66 .; ." 5.71 13.59 15.23 21. 78 17.62 5.70 3.93 1.63 3.05 3.81 11.13 ~ 16.74 24.17 16.90 10.59 3.27 5.05 4.99 4.57 5.53 5.50 12.53 21.02 42.12 22.29 13.69 6.10 0. 64 1 .54 1.74 2.43 5.41 8.63 19.69 13.96 27.77 19.87 40.08 35.08 1.54 3.45 0.11 3.06 4.43 6.42  Appendix I I .  T-R NR ^  46.235 46.235 46.236 46.236 46.237 46.237 46.238 46.238 46.239 46.239 46.240 46.240 46.241 46.241 46.242 46.242  Tl 29.00 29.40 28.15 28.50 26.40 26.65 24.95 24.50 21.25 20.85 28.35 28.85 26.60 27.00 28.25 29.00  T2 41.60 -0. 37.40 -0. -0. -0. 26.50 -0. 22.10 -0. 41.50 -0. ^ -0. 41.40 -0.  TEST DATA OP REFRIGERANT DICHLORODIPLUOROMETHANE (GENETRON-12)  T4  T5  60.50 60.50 51.50 51.50 38.10 38. 10 29.50 29.50 23.85 23.85 61.00 61.00 42.60 42.60 60.40 60.40  95.25 94.85 77.40 77.10 50.25 50.00 34.35 34.70 27.30 27.15 96.20 95.40 59.60 59.00 94.65 93.70  T6  H  -6.40 402.00 -5.80 402.00 -6.20 298.00 -6.00 298.00 -6.40 149.00 -6. 15 149.00 -5.60 72.00 -6.10 72.00 -6.00 49.50 -6.15 49.50 -6.80 407.00 -6.05 407.00 -6.60 200.00 -6.00 200.00 -6.50 398.00 -5.50 398.00  -  (Continued)  TW  DEL T  Q/A  Q  H  QW  22.98 23.46 23.68 24.09 24.23 24.53 24.10 23.57 20.70 20.28 22.19 22.81 23.60 24.09 22.22 23.13  29.38 29.26 29.88 30.09 30.63 30.68 29.70 29.67 26.70 26.43 28.99 28.86 30.20 30.09 28.72 28.63  63560. 62793. 47327. 46702. 22974. 22492. 9069. 9840. 5843. 6084. 65089. 63842. 31762. 30799. 63705. 62074.  1344. 1328. 1001. 988. 486. 476. 192. 208. 124. 129. 1377. 1 350. bTT. 651. 1347. 1313.  2163. 2146. 1584. 1552. 750. /33. 305. 332. 219. 230. 2245. 2212. 1052. 1023. 221S. 2169.  13/1. 1371. 1016. 1016. 508. 508. 246. 246. 169. 169. 1388. 1388. VST. 682. 1357. 1357.  P/li  1.94 3.12 1.50 2.HO 4.37 6. 37 21.68 15.23 26.79 23.77 0.81 2.71 1.50 4.49 C.72 3.27  Appendix  a.  III.  LIST  EQUIPMENT AND  H i g h Vacuum Pump Cat.  No.  Central b.  OP  INSTRUMENTATION  (.HVP) - CENCO H Y V A C ° 7 ,  91506, D r i v e n by Scientific  1/3  No.  2487,  Motor,  Co., C h i c a g o , U.S.A.  Profilometer - Surfindicator, 50/60 c y c l e s ,  G.E.  Serial  M o d e l BL-110, 115  B r u s h I n s t r u m e n t s Co.,  V,  0.25  A,  C l e v e l a n d , Ohio,  U.S.A. c.  S t a n d a r d M e r c u r i a l Barometer  - C a t . No.  Thermometer & I n s t r u m e n t d.  Scale  (SL) - 0 - 1 0 0  e.  Thermometers - j'SM-1, TM-2)  Co.,  Galvanometer cycles,  (GAL) 24  Precision  Philadelphia,  Pa.,U.S.A.  lb. -  0 - 100 66 -  f.  453,  96  °P °P  (l°P (0.05  - Scalamp G a l v a n o m e t e r ,  ohms, The  Ealing  division). °P  PYE,  division) 115  Corp, Cambridge,  U.S.A. g.  h.  (POT)  Instrument  Co.,  0.0000001  volt).  Standard C e l l  60  Mass., :  Potentiometer  No.  V,  ^.  - V e r n i e r P o t e n t i o m e t e r , Cambridge Ltd.-, E n g l a n d ,  (minimum r e a d i n g  (SC) - Weston S t a n d a r d C e l l ,  11644, Weston E l e c t r i c a l  Model  Instrument  4,  Corp.,  . Neward, U.S.A. i.  Variable  Transformer  cycles, j.  Wattmeters  (VT)  ( V a r i a c ) - 115  G e n e r a l R a d i o Co., (WM)  ment C o r p . ,  - 0 - 150 New  watt, S e n s i t i v e  Rochelle,  - 0 - 1000  Cambridge,  N.Y.,U.S,A.  watt.  V,  20 A,  50/60  Mass, U.S.A. Research  Instru-  55o  k.  Thermostatic Limit Switch (TLS) - 60 - 250 °F, 35 A, 125 V.A.C., General E l e c t r i c .  1.  Cold Reference Junction (CRj).  m.  Philips Recording Potentiometer (PRP)  -  Automatic compensa-  tor with 12-channel recording f o r mV and measurements, PR 3216 A/00, N.V. fabrieken, Eindhoven, Holland.  temperature  P h i l i p s ' GloeilampenTo record continuously  the mV reading of each thermocouple  on a 10-inch chart.  The chart was marked off i n 100 intervals which could give a f a i r l y accurate reading to 0.0025 mV on the 1 - mV  range.  n.  Storage Battery (SB) - 6 V.  o,.  Switch Panel (SP) - Double throw double pole switches.  BIBLIOGRAPHY  56. 1.  Z u b e r , N., "Recent T r e n d s i n B o i l i n g Heat T r a n s f e r R e s e a r c h , P a r t 1:• N u c l e a t e P o o l B o i l i n g " , A p p l i e d M e c h a n i c s Review, V o l . 17, No. 9, September 1964»  2.  W e s t w a t e r , • J . W., " T h i n g s We Don't Know About B o i l i n g Heat T r a n s f e r " , from. C l a r k , " F u n d a m e n t a l R e s e a r c h i n . H e a t T r a n s f e r " , Pergamon.Press Inc., I960.  3.  S t e p h a n , I . , "The E f f e e t • o f . O i l on Heat T r a n s f e r of B o i l i n g P r i g e n 12 and P r i g e n 22", A p a p e r p r e s e n t e d a t t h e XI I n t e r n a t i o n a l C o n g r e s s of - R e f r i g e r a t i o n and summarized i n I . I . R„ B u l l e t i n No. 3, 1963.  4»  P o r s t e r , H„ K., and Z u b e r , N., "Dynamics o f V a p o r B u b b l e s and B o i l i n g Heat T r a n s f e r " , A I o Ch.E„ J o u r n a l , December 1955. 0  5.  Z u b e r , N., "On t h e S t a b i l i t y of B o i l i n g Heat T r a n s f e r " , of Heat T r a n s f e r , S e r i e s C, T r a n s . ASME, A p r i l 1958.  6.  Rohsenow, W. M., "A Method of C o r r e l a t i n g Heat T r a n s f e r D a t a f o r S u r f a c e B o i l i n g of L i q u i d s " , T r a n s . ASME, V o l . 74, 1952, and H a r t n e t t , J . P., "Recent A d v a n c e s i n Heat and Mass Transfer".  7.  Hsu, S. T,, " E n g i n e e r i n g Heat T r a n s f e r " ,  8.  H o o g s t r a t e n , A. Van, "A B i b l i o g r a p h y of R e s e a r c h on B o i l i n g " , T h e s i s , U n i v e r s i t y of the W i t w a t e r s r a n d , J o h a n n e s b u r g , J a n u a r y 1964.  9.  Westwater, J . W., " B o i l i n g of L i q u i d " f r o m "Advances i n Chemic a l E n g i n e e r i n g " , V o l . I , 1956, E d i t e d by Drew, T. B. and H o o p e r s , J r . , J . W.  10.  Nukiyama, S., J . S o c . M e c h . E n g r s . 54,  Pages  Journal  418-436, 1963.  ( J a p a n ) , 37, 367, 374»  S53  1934, a s q u o t e d by McAdam [ l 2 J .  11.  K r e i t h , P.,  "Principles  of Heat T r a n s f e r " ,  I960.  12.  McAdams, W. H., "Heat T r a n s m i s s i o n " ,  13.  C o r t y , C , and P o u s t , A. A., " S u r f a c e V a r i a b l e s i n N u c l e a t e B o i l i n g " , Cheim E n g r . P r o g r . Sumposium S e r , V o l . 51, No. 17, 1952.  Pages 368-378, 1954.  0  14.  P o r s t e r , H. K „ , and Z u b e r , N., "Growth of a V a p o r B u b b l e i n a S u p e r h e a t e d L i q u i d " , J . A p p l . P h y s , , 2 5 , 474, 1954.  15.  P u r s e , P. G., "Heat T r a n s f e r t o R e f r i g e r a n t s 11 and 12 B o i l i n g Over a H o r i z o n t a l Copper S u r f a c e " , R e s e a r c h R e p o r t , Department of M e c h a n i c a l E n g i n e e r i n g , U n i v e r s i t y of B r i t i s h C o l u m b i a , March, 1964.  57. 16.  L e v y , S., " G e n e r a l i z e d C o r r e l a t i o n of B o i l i n g Heat T r a n s f e r " , J o u r n a l of Heat T r a n s f e r , S e r i e s C, T r a n s . ASME, F e b r u a r y 1959.  17.  Schweppe, J . L., and F o u s e , A. S», " E f f e c t of F o r c e d C i r c u l a t i o n R a t e on B o i l i n g - H e a t T r a n s f e r and P r e s s u r e Drop i n a S h o r t V e r t i c a l Tube", Chem. Engng. Progr., Symposium, S e r . , V o l . 49, No. 5, 1953.  18.  Long, P. K., E n g l i s h E l e c t r i c Co., L t d . , Whetston E n g l a n d , as q u o t e d by Zuber [ l ] .  19.  Yamagata, K., " N u c l e a t e B o i l i n g o f Water on H o r i z o n t a l H e a t i n g S u r f a c e " , Memoirs of t h e F a c u l t y of E n g i n e e r i n g , Kyushu U n i v e r s i t y , Kukuoka, J a p a n , V o l . XV, No. 1, 1955.  20.  J a k o b , M.,  21.  Farber, Boiling  22.  G u n t h e r , F.C., and K r e i t h , F., "Heat T r a n s f e r and F l u i d M e c h a n i c s I n s t i t u t e " , B e r k e l e y , C a l i f o r n i a , 1949; as q u o t e d by Z u b e r [ 4 ] .  23.  E l l i o n , M. E , , Memo 20-88, J e t P r o p . L a b . , C a l i f . March 1 9 5 4 , a s q u o t e d by Z u b e r [4].  "Heat  Transfer",  Leishester,  V o l . I , 1949, and V o l . I I ,  1957.  E . A., and S c o r a h , R. L., "Heat T r a n s f e r t o Water Under P r e s s u r e " , T r a n s . ASME, V o l . 70, 1948.  0  Inst. Technol.,  

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