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The thermal conductivities of cis and trans decahydronaphthalene Younger, Andrew H. 1946

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(  THE THERMAL-CONDUCTIVITIES OF CIS AND TRANS DEC AHYDRANAPHTHALENE  Andrew H. Younger  A T h e s i s submitted i n P a r t i a l F u l f i l m e n t o f the Requirements f o r t h e Degree of MASTER OF APPLIED SCIENCE i n the Department of CHEMICAL ENGINEERING  The U n i v e r s i t y of B r i t i s h Columbia July,  1946.  ACKWOWLEDGiMENT  The a u t h o r w i s h e s t o acknowledge t h e a s s i s t a n c e o f Donald B . R o b i n s o n w i t h whom t h i s work was c a r r i e d o u t .  He w i s h e s t o acknowledge  t h e a d v i c e and s u g g e s t i o n s g i v e n by D r . W. F . S e y e r , u n d e r whose d i r e c t i o n t h i s r e s e a r c h was undertaken*  TABLE OP CONTENTS Page T  I. I n t r o d u c t i o n I I . The Thermal C o n d u c t i v i t y o f L i q u i d s  1  A. Theory  1  B. Measurement D i f f i c u l t i e s  2  1.  General  2  2» In L i q u i d s  2  C. The Method Used  $  I I I . D e s c r i p t i o n of Apparatus A. The Test C e l l 1.  Calorimeters  2. W a l l s  5 6 6 b  B. The Heaters  7  C. Temperature Measurements  8  D. P o s i t i o n of Thermocouples  9  E . Water Supply  9  F. H e a t i n g C i r o u i t  10 10  IV. Procedure  11  V. R e s u l t s A. Theory o f Measurement  11  B. The Thermal C o n d u c t i v i t y o f Water  11  C. The Thermal C o n d u c t i v i t y o f the Decahydranapthalenes 1.  Preparation of Materials  2. Trans Decahydranapthalene 5. C i s Decahydranapthalene  15 15 lj> 17  TABLE OF CONTENTS ( C o n t ' d ) Page 4. Explanation of Results 71.  S u g g e s t i o n s f o r F u t u r e O p e r a t i o n o f the Apparatus  VII. VIII.  19  20  A. Connections  20  B . Thermopiles  21  C. Container  21  S u g g e s t i o n s f o r F u t u r e Research  21  Conclusion  22  1  THE THERMAL CONDUCTIVITIES OP CIS AND  TRANS  DECAHYDRANAPTHALENE  INTRODUCTION A knowledge o f the thermal c o n d u c t i v i t i e s o f l i q u i d hydrocarbons i s o f importance i n d u s t r i a l l y and  theoretically.  I n d u s t r i a l l y , the thermal c o n d u c t i v i t i e s are of v a l u e i n the d e s i g n of heat t r a n s f e r equipment and i n the compounding o f lubricating oils.  T h e o r e t i o a l l y , thermal c o n d u c t i v i t i e s are  needed to determine the way  hydrocarbons t r a n s f e r heat i . e * by  r o t a t i o n of atoms o r by simple v i b r a t i o n s . Thus our problem has two purposes; f i r s t ,  to b u i l d  an apparatus f o r measuring the thermal c o n d u c t i v i t i e s of v a r i ous l i q u i d hydrocarbons and second, t o continue the  investi-  g a t i o n s a l r e a d y made i n t h i s l a b o r a t o r y on the p h y s i c a l p r o p e r t i e s o f o i s and t r a n s  decahydranapthalene.  THE THERMAL CONDUCTIVITIES OF LIQUIDS Theory The thermal c o n d u c t i v i t y  ,,  K  n  o f a substance i s a  measure of the heat t r a n s f e r through the substance due t o conduction.  I t i s best d e f i n e d by the F o u r i e r e q u a t i o n .  Consider  a s m a l l area dA i n the m a t e r i a l whose thermal c o n d u c t i v i t y i s required.  I f ^© i s the temperature g r a d i e n t normal to dA i n  the d i r e c t i o n x, then the q u a n t i t y o f heat dQ f l o w i n g through  dA i n u n i t time d t i s g i v e n by: dQ In  8  E dA  the steady s t a t e of- heat f l o w the e q u a t i o n becomes Q, » K A  For  A©  l i q u i d s i n p a r t i c u l a r , Bridgeman  1  has worked out  a t h e o r e t i c a l e q u a t i o n whioh checks f a i r l y w e l l w i t h e x p e r i -  2 mental data.  Smith  has used dimensional a n a l y s i s t o o b t a i n  v a r i o u s e m p i r i c a l r e l a t i o n s h i p s t h a t show good agreement w i t h experiment*  However, these equations oan ber used o n l y as  approximations. Measurement  Difficulties  General:  The thermal c o n d u c t i v i t y o f any substance i s  oonsidered t o be one o f the more d i f f i c u l t p h y s i c a l c o n s t a n t s to measure w i t h any degree o f aoouraoy.  One o f the main r e a -  sons f o r t h i s i s the non-existanoe o f an i n s u l a t o r i n the e l e c t r i c a l sense t h a t would enable heat f l o w t o be d i r e c t e d i n any d e s i r e d ohannel.  A l s o t h e r e i s not the i n s t a n t a n e o u s a t t a i n -  ment o f e q u i l i b r i u m that t h e r e i s i n an e l e c t r i c a l In L i q u i d s ; by c o n v e c t i o n . ing  The main problem  system.  i s t o prevent heat  transfer  T h i s i s accomplished i n d i f f e r e n t ways, depend-  on the method used* Flow methods were used by C a l l e n d a r ^ a n d N e t t l e t o n . 4  However, many d i f f i c u l t i e s are encountered i n these methods and u s u a l l y s e v e r a l approximations t h a t oan not always be j u s t i f i e d . Am. Aoad. A r t and S c i . 59 No. 7 141 (1523) 2lhd. and Eng. Chem. 23, 416 (1931) 2phil* Trans. Roy. Soo. 119, 110 (1902) P h . Mag. 19, 587 (1910).  ^roc. 4  3  are r e q u i r e d *  Henoe i n r e c e n t y e a r s no attempts have been  made t o use f l o w methods. Most i n v e s t i g a t o r s have measured the thermal conduct i v i t y w i t h the l i q u i d i n the steady s t a t e u s i n g a t h i n or a t h i c k d i s c .  film  The thermal c o n d u c t i v i t y i s found from t h e  steady s t a t e equation ( g i v e n under t h e o r y ) , a l l the other q u a n t i t i e s i n t h i s equation b e i n g measurable. Two  t y p i o a l examples o f t h i n f i l m methods are  those  o f Kaye and H i g g i n s ^ and Bridgeman^. Kaye and H i g g i n s  1  apparatus  c o n s i s t e d o f an upper  h e a t i n g b l o c k and a lower o o o l i n g b l o c k .  The t h i n f i l m o f  l i q u i d was p l a c e d between these two b l o o k s . the o u t s i d e prevented o v e r f l o w .  A g a l l e y around  A guard h e a t e r above the hot  b l o c k stopped heat from escaping upwards and thus a l l the heat was  t r a n s m i t t e d through the l i q u i d .  The two b l o o k s were separ-  ated a known d i s t a n c e by three g l a s s r o d s .  C o r r e c t i o n s were  a p p l i e d by t e s t i n g the apparatus w i t h a m a t e r i a l o f known t h e r mal c o n d u c t i v i t y . Another type o f f i l m apparatus was d e v i s e d b y B r i d g e mand and used by Smith? and others*  T h i s method c o n s i s t e d o f  u s i n g two c o n c e n t r i c c y l i n d e r s w i t h the l i q u i d between them. The i n t e r i o r o f the c e n t r e c y l i n d e r was heated by a r e s i s t a n c e wire* the heat f l o w i n g r a d i a l l y outwards. was  obtained by measuring the e l e e t r i c a l ^ e n e r g y t o the w i r e ^ ^  ^ r r o o . Roy. 6  The i n p u t o f heat ry  Soc. (London;  A117, 459 (1928j  Loo. C i t .  ^Ind. and JSng. Chem.  22, 1246 (1930;  4.  The temperature d i f f e r e n c e was measured by t h e r m o c o u p l e s and t h e t h i c k n e s s o f t h e f i l m was d e t e r m i n e d by c a l i b r a t i n g w i t h a known l i q u i d .  Thus t h e a c c u r a c y depended on some p r e v i o u s  measurement. The main drawbacks o f t h e t h i n f i l m methods a r e : ( 1 ; d i f f i c u l t y i n measuring t h e t h i c k n e s s o f t h e f i l m (2; s m a l l temperature  drop a c r o s s t h e f i l m .  Bates***^ a p p a r a t u s i s t h e b e s t example o f t h e t h i c k d i s c method.  I n t h i s method t h e l i q u i d i s h e a t e d from t h e t o p  and c o o l e d from t h e bottom and t h u s c o n v e c t i o n c u r r e n t s a r e prevented.  Bates* a p p a r a t u s c o n s i s t e d o f a c i r c u l a r  the w a l l s o f whioh were made o f b a k e l i t e .  oontalner  The t o p was a c e n t r e  h e a t e r and a g u a r d h e a t e r i n s u l a t e d from each other*  The b o t -  tom was a s p i r a l f l o w w a t e r c a l o r i m e t e r surrounded b y a g u a r d r i n g calorimeter*  These were a l s o i n s u l a t e d from e a c h  other.  Thus t h e l i q u i d i n t h e c o n t a i n e r was between two s u r f a c e s a known d i s t a n c e a p a r t . u n i f o r m temperature liquid.  The guard r i n g s were so a d j u s t e d t h a t a  e x i s t e d through h o r i z o n t a l planes i n the  The h e a t f l o w was measured b y t h e s p i r a l f l o w w a t e r  o a l o r i m e t e r , t h e a r e a o f whioh had been d e t e r m i n e d p r e v i o u s l y . The temperature g r a d i e n t t h r o u g h t h e l i q u i d was measured b y thermocouples s t r e t c h e d h o r i z o n t a l l y t h r o u g h t h e l i q u i d .  Thus  a l l t h e terms i n t h e F o u r i e r e q u a t i o n a r e known and t h e r e q u i r e d t h e r m a l c o n d u c t i v i t y can be c a l c u l a t e d . The advantages o f t h i s method a r e :  ° I n d . and E n g ; Ohem. 25, 431 (1933) 9 l n d . and E n g . Chem. 28, 494 (1936)  (1)  I t does not depend on the thermooonduotivity  o f some  o t h e r l i q u i d used t o c a l i b r a t e the apparatus. (2)  The temperature g r a d i e n t through  t h e f i l m can be o b t a i n e d  and thus s u r f a c e e f f e c t s e l i m i n a t e d * v  (3)  I t does not r e q u i r e so a c c u r a t e measurement o f t h e temp-  e r a t u r e d i f f e r e n c e as the f i l m method. The Method Used Our method was an adaption, o f B a t e s .  There were  1  two problems i n p a r t i c u l a r t o be c o n s i d e r e d . of hydrocarbon a v a i l a b l e was l i m i t e d * reduce the volume o f the c o n t a i n e r from apparatus  t o 230  00s. i n our apparatus.  f o r t h e c o n t a i n e r had t o be found lite.  First,  the amount  Thus i t was neoessary t o  2000  cos. as i n Bates*  Seoond a new m a t e r i a l  as " d e c a l i n " * a t t a c k s b a k i -  I t was f i n a l l y d e c i d e d t o use a " t r a n s i t e " * c o n t a i n e r  s i n c e i t had a low thermal deoalin.  c o n d u c t i v i t y and was r e s i s t a n t t o  A problem t h a t arose was how to a t t a c h t h e bottom  c a l o r i m e t e r t o the t r a n s i t s c o n t a i n e r .  After  experimenting  w i t h numerous glues and cements i t was decided t o j o i n the two p a r t s t o g e t h e r w i t h "Lepages"^ glue and cover the o u t s i d e w i t h l i t h a r g e cement and the i n s i d e w i t h p l a s t i o g l u e * v  These mater-  i a l s were r e s i s t a n t t o d e o a l i n . DESCRIPTION OF APPARATUS The equipment c o n s i s t e d o f t h r e e main p a r t s ; a source of water a t constant temperature and p r e s s u r e , t h e t e s t c e l l i n K Commercial name f o r a mixture o f o i s and t r a n s deoahydranapthalene * t r a d e name o f Johns M a n v i l l e L t d . §• trade name Le Page's I n c .  FIG. I  6. its container, and a switchboard as shown in figure 1, The Test Cell The test cell is shown diagramatioally in figure 2. It consisted of a shallow cylindrical container approximately 2 cm. high and 11.5 om* in diameter*  The wall was transits  piping, the bottom was a smooth horizontal water-cooled copper surface, and the top was a removable electrically heated copper surface.  The liquid to be tested was placed in the container  and the heater lowered, forcing any excess liquid out an over flow tube. Calorimeters.  The bottom surface consisted of a test  calorimeter surrounded by a guard ring oalorimeter.  The test  calorimeter was made of a disc of copper approximately 6.98 cm. in diameter and .794 cm. thick, into whioh a continuous spiral groove *476 om. by .476 cm. had been out*  A flat oopper plate  .159 cm. thick was soldered over the bottom and brass T*s were soldered over an inlet and outlet for the cooling water* The side outlet on the T was used as a thermocouple well. The guard ring oalorimeter was made of a *159 cm. annular oopper plate with inside 7.31 om. diameter and outside 13.3 om* diameter.  Copper tubing .476 om. in diameter was  wound in a tight spiral from inside to outside on one surface of the plate, and Soldered in position.  Brass T's were attached  at the inlet and outlet for water openings and thermocouple wells.  The two calorimeters were joined by glycerine - l i t h -  arge oement. Walls.  The transits piping used for the wall was 15*55 cm.  outside diameter, 12.1 cm, inside diameter at the bottom, and  1. THERMOCOUPLE  2.  G L A S 5  3. 4.  TRANS1TE WATER  SPRING  T H E R M O C O U P L E .  ARRANGEMENT  5. G U A R D  G U I D E S  6. T E S T 7  CONTAINER  INLETS  AND  FIG. 2  GUARD  8. T E S T  OUTLETS  GENERAL  R I N G HE A T E R HEATER RING  COPPER  - COPPER CALORIMETER  CALORIMETER  — COPPER  ASSEMBLY OF T E S T C E L L  - COPPER  13.7  om. I n s i d e diameter a t the t o p .  1*98  By c u t t i n g the p i p e  cm, below t h i s change i n diameter on the s m a l l e r s i d e , a oon^ t a i n e r o f the d e s i r e d c a p a c i t y and a convenient  H o r i z o n t a l h o l e s .318  removable heater were o b t a i n e d . meter were d r i l l e d at opposite  support  f o r the om. d i a -  s i d e s of the c o n t a i n e r a t each  of three e q u a l l y spaced l e v e l s between bottom and t o p .  Glass  tubeSjWhioh were f a s t e n e d w i t h p l a s t i o wood i n t o these holes, p r o v i d e d a < guide f o r thermocouples measuring the temperature g r a d i e n t w i t h i n the l i q u i d .  The c a l o r i m e t e r was f a s t e n e d t o  the t r a n s i t e w i t h Le Pages glue and l i t h a r g e - g l y c e r i n e oement, A oopper overflow tube was i n s e r t e d about .159  cm. above the  top o f the c o n t a i n e r . Heaters The  top s u r f a c e c o n s i s t e d of a guard and t e s t  the same s i z e as the c a l o r i m e t e r s .  The copper was .476  heater cm*  t h i c k w i t h a narrow flange" on i n n e r and outer edges making the edges  *953  om, t h i o k .  e r i n e - l i t h a r g e cement*  The two h e a t e r s were f a s t e n e d w i t h Heat was p r o v i d e d f o r t h e t e s t  heater  by a 25 ohm p i e c e o f niehrome ribbon'wire wound u n i f o r m l y mica, and f o r the guard r i n g by a 53  glyc-  over  ohm p i e c e wound s i m i l a r l y *  G l y p t a l and a sheet o f mica i n s u l a t e d the h e a t i n g elements from the oopper.  The niehrome ends were f a s t e n e d t o b i n d i n g p o s t s  screwed t o a t h i n p i e c e of t r a n s i t e board p l a c e d over t h e two heaters,  A t h i n s t e e l c y l i n d e r 12,7  cm. h i g h was f a s t e n e d a t  the bottom around the h e a t e r and packed w i t h rook wool i n s u l a tion.  The h e a t e r s oould then be r a i s e d o r lowered onto the  surface of the l i q u i d under t e s t .  8* The complete c e l l was p l a c e d a t the c e n t r e of a 30.5  om. by 43*7  w i t h 85% magnesia  om. diameter s t e e l drum and packed underneath and around the s i d e s w i t h rook wool as shown  in figure 2. Temperature Measurements A l l temperatures were measured by thermocouples made from #30 B. and S. gauge c o p e l and #36 B:. and S. gauge oopper junctions.  A C a l i b r a t i o n curve f o r t h e s i n g l e j u n c t i o n was  drawn u s i n g r e s u l t s o b t a i n e d by comparing r e a d i n g s o f t h e CopperCopel those o f a standard Copper-Constantan same temperature.  junction at the  The curve was checked a t t h e steam p o i n t and  at the benzene b o i l i n g p o i n t . I n l e t and o u t l e t temperatures o f t h e o a l o r i m e t e r water were measured by f o u r - j u n c t i o n t h e r m o p i l e s which were checked a g a i n s t a c a l i b r a t e d s i n g l e j u n c t i o n  thermocouple*  The c o l d j u n c t i o n s were kept a t 0°C i n crushed i o e and i n no case was a oommon o o l d j u n c t i o n u s e d .  The thermos  oouple l e a d s were brought to a u n i f o r m temperature* zone box and from there through #18 Copper l e a d s t o a r e v e r s i n g switoh* T h i s switoh, as shown i n f i g u r e 3t r e v e r s e d the d i r e c t i o n o f the E.M.F. through a l l c o n n e c t i o n s t o the p o t e n t i o m e t e r .  By  a v e r a g i n g both r e a d i n g s , any s t r a y emf * s. a r i s i n g i n t h a t p a r t • • of the c i r c u i t were e l i m i n a t e d .  Copper t o oopper c o n t a c t s  were used throughout. The p o t e n t i a l s were measured w i t h a Leeds and Northup potentiometer No. 8662 where emf*s c o u l d be e s t i m a t e d t o one miorovolt.  S i n c e the oopper-oopel j u n c t i o n gave approximately  a 40 m i c r o v o l t change p e r degree, i t was thought  temperatures  POTENTIOMETER  FIG. 3  THERMOCOUPLE CIRCUIT  9. were aocurate a t l e a s t to 0.1°C  f o r the s i n g l e j u n c t i o n and  0.01°C f o r the t h e r m o p i l e . P o s i t i o n of  Thermocouples  The p o s i t i o n o f a l l thermocouples i s shown i n f i g u r e 4. F i v e thermocouples were p l a c e d i n the same r e l a t i v e p o s i t i o n i n b o t h the h e a t e r and c a l o r i m e t e r s u r f a c e s * test  The  s u r f a c e s had t h r e e j u n c t i o n s spaced u n i f o r m l y over the  area*  They were i n s e r t e d i n h o l e s d r i l l e d p a r a l l e l t o and  beneath the s u r f a c e .  The  j u n o t i o n was  and s o l d e r e d i n the d e s i r e d p o s i t i o n .  just  brought to the s u r f a c e The guard r i n g s each had  two thermocouples spaced l 8 0 ° a p a r t , i n s e r t e d ' j u s t beneath the surface*  A l l thermocouples i n the h e a t e r were c a r e f u l l y  eleo-  t r i o a l l y insulated. The temperature w i t h i n t h e l i q u i d was measured at d i f f e r e n t l e v e l s by t h r e e e q u a l l y Bpaced thermocouples guided by t h i n g l a s s tubes shown i n f i g u r e 2*  The i n d i v i d u a l  thermocouple  l e a d s were then f a s t e n e d to a moveable b r a s s s l i d e r r e s t i n g a weak compression s p r i n g whioh was  on  f i x e d a t i t s lower end.  By  f i x i n g the thermocouples i n p o s i t i o n w i t h the s p r i n g s under s l i g h t compression, any expansion o f the w i r e caused by h e a t i n g was  overcome and the j u n c t i o n s were h e l d without sagging at a l l  times* Water Supply Constant temperature and constant p r e s s u r e water s u p p l i e d by a c o n t a i n e r p l a c e d 4 f t * 6 i n . above the t e s t Constant l e v e l was  was cell.  o b t a i n e d by u s i n g a c e n t r a l o v e r f l o w tube.  FIG. 4  THERMOCOUPLE POSITIONS  10. The water was  heated by a v a r i a b l e 0-.500 watt h e a t e r supple-  mented by two  thermostatically c o n t r o l l e d k n i f e heaters*  vapour p r e s s u r e thermostat kept the temperature  A  constant t o  0.05°C Heating  Circuit The h e a t i n g c i r c u i t i s shown i n f i g u r e 5 .  was  s u p p l i e d by 12-  ing  arrangement enabled c u r r e n t i n both c i r c u i t s  one ammeter. ammeter was  and 4 0 - v o l t storage b a t t e r i e s *  Current The  switch-  to be read  on  Both h e a t e r s operated at a l l times whether the i n or out o f the  circuit.  PROCEDURE A f t e r the bath h e a t e r and the t e s t c e l l was  f i l l e d t o the o v e r f l o w tube.  b e i n g t e s t e d had been heated d r i v e out d i s s o l v e d gases* ing  s t i r r e r had been s t a r t e d ,  the excess l i q u i d  The  liquid  above any t e s t temperature The h e a t e r was  then lowered,  out the o v e r f l o w tube.  The  was  the bottom s u r f a c e temperatures  until  adjusted u n t i l  were u n i f o r m .  About 4 t o 6 hours were r e q u i r e d to . a t t a i n  equilibrium.  A f t e r one hour at e q u i l i b r i u m r e a d i n g s were reoorded. t h e r m o p i l e s were r e a d every 10 minutes f o r one hour and  constant.  checked  The r a t e was  was  o b t a i n e d at both h e a t i n g s u r f a c e s .  The water f l o w i n g through the c a l o r i m e t e r was  water r a t e was  forc-  current  switched on and a d j u s t e d i n the oentre and guard r i n g the d e s i r e d temperature  to  The the  every lj> minutes to make sure i t was measured by c o l l e c t i n g the water i n a  graduated c y l i n d e r f o r a p e r i o d o f five,  minutes.  t  GUARD  HEATER  VVVIAAVWWVVTE.ST  FIG. 5  HEATER  HEATING CIRCUIT  11 RESULTS Theory of Measurement The steady  state  thermal c o n d u c t i v i t y was  determined from the  equation K  Q - the heat f l o w .  s  QOI  T h i s was  found by measuring the r a t e of  flow o f water through the t e s t c a l o r i m e t e r and the i n l e t o u t l e t temperature of the water. one hour was AX  average d i f f e r e n c e over  taken as the temperature d i f f e r e n c e *  - the distanoe between the two  couples  The  and  s u r f a c e s or two  s t r e t c h e d through the l i q u i d .  o f the thermo-  These d i s t a n c e s were  measured by a depth guage* AT  - the temperature d i f f e r e n c e between the two  points i n  question. A - the area of t e s t  calorimeter.  The Thermal C o n d u c t i v i t y o f Water To t e s t the apparatus i t was  decided to measure the  thermal c o n d u c t i v i t y o f d i s t i l l e d water*  The  value f o r water  has been obtained by a number o f i n v e s t i g a t o r s and i n r e c e n t y e a r s i t s value has been f a i r l y w e l l e s t a b l i s h e d . ing  t a b l e g i v e s some of the l a t e r v a l u e s  obtained.  The  follow-  12.  Observer  Year (Cal^cT  Cm' )  1  1  1920  .00144  Bridgeman  1923  .00144  Davis  1924  .00146  Kaye and Higgins  1928  ,00151  Smith  1930  ,00144  Bates  1936  ,00145  Jakob  1 0  The f o l l o w i n g data and r e s u l t s were o b t a i n e d f o r water.  The a r e a o f the o a l o r i m e t e r was 3 7 . 6 6  sq. cms. The  d i s t a n c e between the thermocouples was  # 1  t o #11  s  1*201 cms.  # 1  t o #18  s  #18  t o #11  .546  cms.  .655  oms.  s  The t r u e thermal c o n d u c t i v i t y was found by u s i n g the d i s t a n c e between thermocouples #1 t o #11.  Justification for  u s i n g the d i s t a n c e between thermocouples i s shown i n the graph of the temperature g r a d i e n t through the l i q u i d  ( ig. 6 ) . F  A t y p i c a l data sheet f o r water f o l l o w s :  Run  Date: June 2 6 , 1946 S t a r t : 12:00 A.M. Time TC#  1 0  1 2 5 4 5 18 7  2*00  3.00  4.00  5.00  5.30  7.30  1^56 1752 1748 730 730  1577 1775 1772 730 730 1305 730  1587 1784 1783 736 736 1312 738  1595 1792 1790 736 736 1316 739  1598 1806 1805 734 734 1318 739  1599 1809 1812 731 731 1320 733  1294  733  A n n . Physik. 6 3 , 5 3 7 P h i l . Mag. 47, 922  1 : L  (1920) (1924)  #7  Its  13 2.00  3.00  4.00  5.00  5.30  7.30  1748  1771  1782 742 1781  1790 750 1790 979 178I 739 .219 .610 430  1800  1810  Time TC#  Current (amps) Volts  8 9 10 11 12  742  1749 970 1740  15  736 .220 .610  C G  431  746  1771 974 1762 738 .220 .610 43J.  977  1773 732 .220 .610 43.0  744  1800 978 17 90 736 .219 .610 43.0  743 1800 978 1799 732 .219 .610 43i>  »*>crovo Ik  "  Thermopile r e a d i n g s and water r a t e . Time  WHcrovalT*  0 10  2846 2844 2837 2838 2851 2851 2828 28^5  20  30  40  50  60 70  80 90 100 110 120  2844 2841 2840 2841 2841  m  .  ,. •.. : J v..  2950  2948 2939 2948 2950 2948 2953 2964  612 612 612  2961  2960 2962 2961 2960  612 612  C a l c u l a t i o n o f Thermal C o n d u c t i v i t y K -  ftaX  A - 37»66 sq.cm. AX  -  1.201 so,.cm.  (Distance  between  #1 and #11)  AT -  1.598 - *978 = 620 m i c r o v o l t s  = 15.50 °C. ft - Average #13 " 11  #16  2.953*3 2.842.9  D i f f e r e n c e s 111.4 m i c r o v o l t s  Water r a t e 5 6.I3  oc/min.  14, s 111.4 K  s  (612)  i7H cals/sec.  3  .711 (1.201)  .00146  s  oals  37.bb (15.50)  at  om. "C sec.  32*8 °C.  F o r v a r i o u s temperatures, f o l l o w i n g t a b l e were obtained: AT ax Heat Run Top OC No. Surface oms. Flow Tgmp. a G Cals/13eo  5  37.5  1201  .436  7 8  456  1201  59.2  1201  •711 1138  9  43.2  1201  -579  A comparison o f Bates* temperature i s g i v e n i n the next Temp. °e  the r e s u l t s g i v e n i n the  A  cm 2  c  E cal/.om-°Cseo  Temp o f reading o c  5174 37.66  .00143  272  37.66  .00146  32£  2514 37.66  .00145  39-3  12JS5 37.66  .00146  29.6  W0  v a l u e s w i t h these a t t h e same table. Kc  Bates E,  27  .00143  .00144  30  .00146  .00145  33  .00146  .00146  39  .00145  .00148  C o n s i d e r i n g how c l o s e the temperatures  c o u l d be read  and v a r i e t y o f r e s u l t s o b t a i n e d by other i n v e s t i g a t o r s , i t was decided t h a t the above r e s u l t s showed t h a t t h e apparatus was s a t i s f a c t o r y f o r measuring the thermal c o n d u c t i v i t i e s o f l i q u i d s .  15. The Thermal C o n d u c t i v i t i e s o f the Decahydranapthalenes P r e p a r a t i o n of M a t e r i a l s The  s e p a r a t i o n o f d e c a l i n i n t o i t s c i s and t r a n s  isomers was done by r e c t i f i c a t i o n i n a Stedman oolumn a t 9 mm. pressure* about  The p u r e s t f r a c t i o n o f each isomer from t h i s was  99«5f». The p u r e s t f r a c t i o n o f the c i s isomer was then  fur-  t h e r p u r i f i e d by s u c c e s s i v e r e c r y s t a l l i z a t i o n i n a dry i c e bath u s i n g the method o f Seyer and W a l k e r . ^  A f t e r repeated  c r y s t a l l i z a t i o n a constant value f o r the f r e e z i n g p o i n t o f 43.31  was o b t a i n e d .  T h i s was c o n s i d e r e d t o be the p u r e s t sam-  ple of cis decalin available.  i  I n a s i m i l a r manner the t r a n s isomer was r e c r y s t a l l i z e d u n t i l a constant f r e e z i n g p o i n t o f -  30.76  was o b t a i n e d .  These  samples were then used f o r the measurements. Trans Decahydranapthalene The f o l l o w i n g are the r e s u l t s f o r the thermal d u c t i v i t y o f t r a n s deoahydranapthalene.  A d a t a sheet and c a l -  c u l a t i o n s are f o l l o w e d by a t a b l e of v a l u e s . the v a r i a n c e o f thermal  c o n d u c t i v i t y with  TC#  1  Run #22  2*00  4.00  5.00  5*30  1642  1691  1700  1701 1954  2 1888 3 1916 4 710 5 710  1946 1975 712 712  1953 1982 714 714  1982 715  714  6.00 1702  1956 1984 712 712  A n g l e y P o t k i n s and Rush - B a c h e l o r T h e s i s 13jiA.C.S. 60, 2125 (1938)  l 2  F i g u r e 7 shows  temperature.  .Date: J u l y 12 S t a r t : 11:30 A.M. Time  con-  1942.  mier«vo»K  16 2.00  4.00  5.00  £.30  6.00  18 1344 7 711 8 1915 9 734 10 1915  1366  1373  1375  1376 712  15 726 C .115 G .502  726 .115  Time TC#  712 1975 735  1975  11 1011 12 1881  Current (amps) Volts  IP 1981 738  1981 1024 1943  1022 1932  730 .115 .502  •502 42  42  42  1982 738 1982 1024 1943 730  .115 .502 42  1984 736 1984 1024 1945  726 .115 .502 42  Its #16  #13  0 10 20 30  2811 2819 2816  50 60  2814  2857 2859 2858 2857 2858 2860 2857  Time (Minutes)  2814  2811  40  2818  WR -ec/5m.  261 261  Calculations:  A • 37.66 sq,. cm. I »  1.222 cm*  T s 1.701 - 1.024 40"  ft s 2.858 ^TfaU K =  m  16.74 °C  (261) (W)  2.815  s  .234 c a l s / s e c  *234 (1.-222) 37.bb (IS.74) r .000455 Q&1 om - sec C  at 35.8 °C. The temperatures.  f o l l o w i n g r e s u l t s were o b t a i n e d f o r v a r i o u s  ~Y ///£,><  C OV^C/CTV Vf'y  c<t^s  17* Run No.  15 16 18 19 21 22 23 Cis  Top Surface Temp. °C 37-2 25.3 58.8 25.3 24.7 49-5 82.0  Heat Flow  AX cms*  -AT °C  A om  10.71 £33 2195.: 3.75 £25 16.74 3940  37.66 37.66 37-66 37.66 37-66 37.66 37-66  K Temp o f oal/om-°C reading - sec  2  ft  c a l s / sec 1222 1222 1222 1222 1222 1222 1-222  .1366 .0464 .309 .0558 .0487 .234 .647  310 217 3*8 216 214 3£8 526  .000413 .000454 .000457 .000483 .000484 .000455 .000534  Deoahydranapthalene The f o l l o w i n g a r e t h e r e s u l t s f o r t h e t h e r m a l con-  d u c t i v i t y o f c i s deoahydranapthalene.  A d a t a sheet and c a l c u -  l a t i o n are f o l l o w e d by a t a b l e o f v a l u e s . variance of thermal c o n d u c t i v i t y with  temperature.  Date: J u l y 1 6 , 1946 S t a r t : 1 1 : 0 0 P . M . J u l y 15 Time TC#  Current Volts •  1 2 3 4 5 18 7 8 9 10 11 12 15 C 0  F i g u r e 8 shows t h e  Run #31  9.00  9.30  10.00  10.30  880 970 981 692 708 832 710 981 714 983 761 970 714 .056 .225 13  880 972 981 692 710 833 710 982 715 984 762 971 714 .056 .225 13  882 973 983 695 710 833 710 983 715 986 770 971 715 .056 .225 13  888 973 985 695 710 841 710 985 716 988 769 974 715 .056 .225 1?  I* Krovolts II It . It  u ll It  « ft 11 11 11 11  Time Minutes  Outlet Inlet mtcrovo ifrs  0 5 10 15 20 25 30 35  40  45 50 55 60  Ave.  WR 0 0 / 5 min*  2832 2828 2828 2830 2832 2832 2834 2834 2836 2832 2832 2831 2831  2816 281? 2816 2819 2815 2819 2818 2818 2818 2817  28317  28I7.5  202  204 203  2817 2818 2818  203  Calculations: 37*66  A m  sq>  cms.  A£ a  1*222 cms.  ^  8 8 5 - 7 6 7 - 2.95°C 40  T  •  Q, m  142(203)  • K .  * . 0 6 0 1 cals/seo.  .0601 (1.222) • .000656 o a l s . 37.66 (2.^5) cm - seo C u  at  21.2°C. The f o l l o w i n g r e s u l t s were obtained a t v a r i o u s  temperatures. Run No.  Top Surface Temp.  2b 28  5^1  29  510  30 31  32 33  519 .  7&6  25.3 35-8 41-1  cms.  .670 •670 1222 1222 1222 1222 .670  Heat Flow  a.  C a l s / seo  AT °C  .371  IbO  .301  & 3 1£06  •359 .671 .060  36.95 2.95  .407 2110  .229  >n  K  cm*  1  37.66 37-66 37.66 37.66 37.66 37.66 37-66  K Cals cm-sec °C  Temp, o f reading °C  .000724  319  .000773 .OOO656 .006£$6  528  .00O2£Z.  37.4 319  .000660  .000^4  3Q2 3M 212  19* Explanation of Results The reasons f o r the e r r a t i c r e s u l t s o b t a i n e d f o r t h e thermal c o n d u c t i v i t y o f the deoahydranapthalenes may he as follows: 1, Leakage o f the c o n t a i n e r .  Great d i f f i c u l t y was  encountered i n making the c o n t a i n e r impervious t o d e c a l i n .  To  prevent leakage the whole o f t h e i n s i d e o f t h e c o n t a i n e r was covered w i t h "Oenoo" l a b e l v a r n i s h whioh was s a t i s f a c t o r y f o r two o r t h r e e runs but e x t r a c o a t s were then r e q u i r e d .  The l a b e l  v a r n i s h decreased t h e c o n d u c t i v i t y o f t h e bottom metal s u r f a c e s whioh r e s u l t e d i n a l o n g e r time b e i n g n e c e s s a r y t o reaoh e q u i l ibrium.  The l a b e l v a r n i s h a l s o i n c r e a s e d the l i k e l i h o o d o f heat  l o s s down through t h e t r a n s i t e t o t h e bottom 2. The i n l e t  surface.  t h e r m o p i l e #16 s t a r t e d t o read too h i g h .  T h i s was p r o b a b l y because heat was conducted a l o n g t h e thermop i l e from the o u t s i d e o r because t h e t h e r m o p i l e was t o u c h i n g the  metal i n t h e t e e .  The t h e r m o p i l e was removed and an attempt  was made t o f i x i t but a f t e r a few runs i t a g a i n read h i g h . Thus t o o b t a i n the i n l e t the  temperature i t was n e c e s s a r y t o remove  h e a t e r and r u n the water through as f a s t as p o s s i b l e and  thus be unable t o p i c k up any heat* gave the i n l e t  #13 was then read and t h i s  temperature o f the water*  s a t i s f a c t o r y as i t d i d n o t g i v e t h e i n l e t same time as "the o u t l e t  T h i s was not completely temperature a t t h e  temperature.  The o b t a i n i n g o f a h i g h e r thermal c o n d u c t i v i t y f o r t h e c i s isomer as compared w i t h t h e t r a n s isomer i s t o be expected. T h i s c i s form has a h i g h e r d e n s i t y , i . e . the molecules a r e  20; c l o s e r together,  and thus i t should be able t o t r a n s f e r heat  more r e a d i l y * SUGGESTIONS FOR FUTURE OPERATION OF APPARATUS Connections One o f the main d i f f i c u l t i e s  i n t h i s experiment was  keeping the l i q u i d s from p e n e t r a t i n g the oements used t o f a s t e n the c e l l t o g e t h e r .  Over the p e r i o d o f time n e c e s s a r y f o r  e q u i l i b r i u m , d e c a l i n would seep through g l y c e r i n e - l i t h a r g e cement*  G l y p t a l and other patent  organic  protective"coatings  are q u i t e s o l u b l e i n c i s deoahydranaphthalene.  Le Pages glue  i s s o l u b l e i n d e o a l i n u n l e s s baked at 100°C f o r two hours o r more. at  n  Cenco  l a b e l varnish i s r e s i s t a n t to deoalin but softens  tt  about 8o°C.  I t i s too t h i n t o be o f any use i n j o i n i n g two  p i e c e s of metal, o r metal and t r a n s i t e , but pan be used t o coat a more p e r v i o u s but r i g i d The  cement.  two best oements found f o r t h e job were Wfcldwood  P l a s t i c R e s i n and S a u r e i s i n L i q u i d P o r c e l i n . only u s e f u l i n t h i n l a y e r s .  The S a u r i e s e n i s  The W*ldwood i s u s e f u l i n t h i n  c o a t i n g s o r t h i c k l a y e r s and i s t h e r e f o r e the most convenient to use f o r j o i n i n g the p a r t s o f the c e l l . Before gested  f u r t h e r measurements a r e attempted, i t i s sug-  t h a t the c a l o r i m e t e r be separated  the g l a s s thermocouple tubes removed.  from t h e t r a n s i t e and  After c a r e f u l cleaning,  the p a r t s should be reassembled u s i n g W&ldwood f o r a l l connections.  The g l a s s tubes should be r e i n s e r t e d and f i x e d  W*ldwood.  At l e a s t f o u r days should be allowed  with  f o r the cement  to harden u n l e s s the l a y e r i s v e r y t h i n , when two days w i l l be sufficient.  21* Thermopiles. Some d i f f i c u l t y was encountered ings o f the water i n l e t temperature  i n g e t i n g true read-  t o the c a l o r i m e t e r .  I t was  at f i r s t f e l t t h a t t h e i n s u l a t i o n had f a i l e d c a u s i n g metal t o metal c o n t a c t o f t h e b r a s s and the t h e r m o p i l e , however, examina t i o n r e v e a l e d no f l a w s i n the i n s u l a t i o n .  S i n c e the t h e r m o p i l e  l e a d s were o n l y immersed i n the water about h a l f an i n c h at t h e hot j u n c t i o n , i t was thought  some heat might have been  a l o n g the w i r e s to t h e j u n c t i o n oausing too h i g h a  conducted  temperature  to be read* I t i s suggested  t h a t the p o s i t i o n o f the t h e r m o p i l e  hot j u n c t i o n s be changed so t h a t the incoming and outgoing water flows over at l e a s t  s i x Inches o f the l e a d w i r e s  p r e c e d i n g the J u n c t i o n s .  immediately  I f the l e a d w i r e s were encased  in a  t h i n g l a s s tube w i t h o n l y the j u n c t i o n i n the f r e e stream, a minimum r e s i s t a n c e would be o f f e r e d t o the f l o w o f t h e l i q u i d p a s t the w i r e s .  The j u n c t i o n should be i n s u l a t e d so t h e r e i s  no p o s s i b l e chance o f c o n t a c t between the j u n c t i o n and the brass connection. Container C o n s i d e r a b l e d i f f i c u l t y was experienced i n f i x i n g the c e l l t o the water pipe connections owing t o the i n a o c e s s a b i l i t y of the connections.  I t i s suggested  t h a t a l a r g e * window be  out i n the o u t s i d e metal c o n t a i n e r t o improve v i s i b i l i t y when working around the c e l l when i t i s i n p o s i t i o n . SUGGESTIONS FOR FUTURE RESEARCH The apparatus  should, w i t h minor adjustments,  enable  22..  the  thermal c o n d u c t i v i t i e s o f v a r i o u s l i q u i d hydrocarbons t o  be measured.  There i s need o f c o n s i d e r a b l e work i n t h i s  field  as v e r y l i t t l e has been done* The thermal o o n d u o t i v i t y o f the o i s and t r a n s isomers of v a r i o u s other o r g a n i c compounds c o u l d a l s o be i n v e s t i g a t e d to  see whether o r not the o i s isomer has a h i g h e r o o n d u o t i v i t y  i n every case. CONCLUSION An apparatus f o r measuring the thermal o o n d u o t i v i t y of  l i q u i d s has been b u i l t *  I t was found t o work s a t i s f a c t o r i l y  by t e s t i n g i t w i t h d i s t i l l e d water, the thermal c o n d u c t i v i t y o f which had been determined p r e v i o u s l y by a number o f i n v e s t i g a tors* of  The thermal c o n d u c t i v i t i e s o f the o i s and t r a n s isomers  deoahydranaphthalene  were a l s o measured.  Although somewhat  e r r a t i c r e s u l t s were o b t a i n e d f o r these compounds i t was found t h a t i n a l l oases the o i s isomer had a h i g h e r thermal t i v i t y than the t r a n s isomer*  conduc-  With t h i s apparatus c o n s i d e r a b l y  more i n v e s t i g a t i o n s oan be c a r r i e d out p o s s i b l y a l o n g the l i n e s suggested.  

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