University of Southern California Dissertations and Theses

The enthalpy of isopentane

(USC Thesis Other)

The enthalpy of isopentane

PDF

Download

Open document

Flip pages

Download a page range

Download transcript

Copy asset link

Request this asset

Transcript (if available)

Content THE ENTHALPY OF ISOPENTANE A Thesis Presented to The Faculty of the School of Engineering The University of Southern California In Partial Fulfillment of the Requirements for the Degree Master of Science in Chemical Engineering By Walter John Stupin August 1963 UMI Number: EP41779 All rights reserved INFORM ATION TO ALL USERS The quality of this reproduction is dependent upon the quality of the copy submitted. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if material had to be removed, a note will indicate the deletion. UMI EP41779 Published by ProQuest LLC (2014). Copyright in the Dissertation held by the Author. Dissertation Publishing Microform Edition © ProQuest LLC. All rights reserved. This work is protected against unauthorized copying under Title 17, United States Code ProQuest LLC. 789 East Eisenhower Parkway P.O. Box 1346 Ann Arbor, Ml 4 8 1 0 6 -1 3 4 6 TVzzV thesis, w ritte n by Walter..Jpto„ 17 fo under the guidance o fh -ls F a c u lty Com m ittee and approved by a ll its members, has been presented to and accepted by the School of E ng ineering in p a rtia l fu lfillm e n t o f the re quirements fo r the degree of Master of Science In ............. D ate. August... 12.63. F aculty Committee Chairm an ACKNOWLEDGMENT I wish to thank my committee chairman and adviser, Dr. J. M. Lenoir, for his constant encouragement and advice during this research project. I also wish to express my appreciation to Dr. C. J. Hebert for his helpful suggestions during the entire research. Finally, I wish to acknowledge the efforts of my wife, Barbara, and Mrs. Ruth Toyama in the work of completing this thesis. TABLE OP CONTENTS Page INTRODUCTION ......................... 1 EQUIPMENT AND EXPERIMENTAL PROCEDURE ................ 2 RESULTS .......................... 6 DISCUSSION OP PARAMETERS AFFECTING CALORIMETER PERFORMANCE........................ .............. 11 ACCURACY OF THE MEASUREMENTS ..................... l£ CONCLUSIONS ..................................... 19 BIBLIOGRAPHY.................. 2$ APPENDICES ................ 27 Appendix A - Equipment ........... 28 Appendix B - Procedures .... 37 Appendix C - Miscellaneous Data............. 39 Appendix D - Calculations .........*........ l\ . 2 Appendix E - Raw Data £l iv LIST OP TABLES Table No, Page I Corrected Enthalpy Data - Isopentane ........ 20 II Two Phase Data - Isopentane ......... 2 1 $ . Ill Calibration of the Freon-11 Receiver ........ 28 IV Calibration of the Hydrocarbon Receiver ..... 35 V The Effect of Freon-11 Liquid Level on Calorimeter Performance ................... 39 VI The Effect of Outer Can Heater Duty on Measured Enthalpy ............ l j . 0 VII Raw Data.................................. 51 v | LIST OP FIGURES Figure No. Page 1 Experimental Apparatus ............... 3 2 Enthalpy of Isopentane . .*....... 7 3 Comparison of These Data to the Correlation of Maxwell ............. 9 4 Vapor Pressure of Isopentane ..... 10 5 Effect of Liquid Level on Calorimeter Performance ............................... 13 6 Effect of Outer Can Heater on Calorimeter Performance l l } . 7 Correction for the Effect of Outer Can Heater Duty ...................... 14 8 Heat Leak Around Hydrocarbon Inlet .......... 16 9 Freon-11 Receiver .................... 29 | t 10 Volume Correction for Freon-11 Receiver ..... 30 11 Hydrocarbon Receiver 34 J 12 Density of Liquid Isopentane ...... 45 13 Specific Volume of Isopentane ...... 4& 14 Enthalpy vs. Pressure-Liquid Isopentane <§ 75°F .................................... 48 15 Enthalpy Pressure Diagram - Isopentane 49 j 16 Enthalpy Correction for Small Pressure j Differences ....... £0 1 vi INTRODUCTION For the design of almost all chemical processing equipment, the knowledge of the thermodynamic properties of the fluids involved is necessary. At low pressures (the ideal gas state) the thermo dynamic properties of most materials can be predicted by statistical methods or have been experimentally determined# Enthalpy, entropy, and heat capacities for most hydro carbons in the ideal gas state can be found in API Project (1). The deviation of the thermodynamic properties from that of the ideal gas state can be calculated from P.V.T. data by thermodynamically exact equations. The problem with this approach is that these equations require the partial derivatives of the P.V.T. functions. Therefore, the P.V.T. data have to be very precise for the derived thermodynamie properties to have good accuracy. This approach has been taken by several investigators and the thermodynamic properties of the lighter hydrocarbons have been calculated. Actual thermal data in the region of the critical point are rare. For Isopentane, P.V.T. data have been published by Isaac, Li and Canjar (3)> and Young (6,7)• The enthalpy in the gas phase has been calculated from P.V.T. data (1). 1 2 The objective of this research was to determine the enthalpy of isopentane in the region of the critical point and at the same time determine the reliability and preci sion of enthalpy values determined by a flow calorimeter in the Department of Chemical Engineering at the University of Southern California. EQUIPMENT AND EXPERIMENTAL PROCEDURE The equipment consists of a flow calorimeter as shown in Figure 1. A complete description of the calori meter is given by Couch (2). The enthalpy difference of the fluid in the high pressure tubing is determined between the inlet and the outlet temperatures at the pressure in the condensing coil. The hydrocarbon enters the calorimeter at a pressure set by the throttling valves and a temperature determined by the heat duties of the three hydrocarbon heaters. These heaters are controlled manually by variable voltage supplies. The heat in the hydrocarbon is transferred to the boiling Freon-11 as the hydrocarbon cools to the boil ing point of the Freon-11. The Freon-11 in the outer can is kept at its bubble point by heat supplied externally from the outer can heaterj this tends to keep heat from being transferred between the two cans. This heater was installed to eliminate a heat leak which existed because Figure 1 Experimental Apparatus M M X A- Calorimeter, B- Freon-11 (N.B.P. 7^.8°F), C- Inlet Thermocouple location, D- Freon-11 vapor collector and *n- trainment separator, E- Throttling valve, F- Freon-11 re ceiver, G- Hydrocarbon receiver, H- System pressure (Heise gage), I- System pressure gage, J- Line filter, K- Milton Roy pump, L- Feed bomb, M- Feed bomb and re ceiver pressure, N- Hydrocarbon heaters, 0- Outer can heater, P- Pump discharge pressure; Q- Rupture disk, R- Back pressure diaphragm, S- Reflux condensers, T- Dry ice-acetone condenser, valves . ' ^ k the ambient temperature around the calorimeter was usual ly well below 7J?°F, the boiling point of the Freon-11. During the initial period of operation this heater is also used to bring the temperature of the calorimeter and con tents up to the boiling point of the Freon-11. The Freon- 11 from the inner can is collected in a volumetric receiver after it is condensed in a reflux condenser. The Freon-11 is recycled immediately back to the outer can except during the period of measurement. The hydrocarbon flows out of the calorimeter through the throttling valves to the feed bomb except during the period of measurement when the hydrocarbon flows in to the measuring receiver. The procedure followed during an enthalpy determin ation was the following: 1. The valve vdiieh allows the hydrocarbon to flow into the feed bomb was closed. 2. The valve which returns the Freon-11 to the outer can was closed. 3. The level in Freon-11 receiver was read. I ) . . The level in hydrocarbon receiver was read* 5>. The Freon-11 and hydrocarbon levels were recorded. 6. The required temperatures were recorded. ?• The hydrocarbon outlet pressure was recorded. 8. After sufficient volumes of hydrocarbon and 5 Freon-11 were collected steps 3» 4 and 3 > were repeated* 9* The valve returning Freon-11 to the outer can was opened. 10. The valve returning the hydrocarbon to the feed bomb was opened. The primary measurements were the volumes of Freon-11 and hydrocarbon. The enthalpy was calculated using the density and heat of vaporization of Freon-11 at barometric pressure, the density of the hydrocarbon at room temperature and the pressure in the receiver. The calculation is very simple and is given by: . x r a /° f-ii vf-ii % - n Hydrocarbon ipY) Hydrocarbon After each enthalpy determination was made, the change in enthalpy through the calorimeter was calculated. After about 1$ minutes this enthalpy difference was remeasured. If there was no appreciable change in measured enthalpy over the 15-minute interval, the hydrocarbon inlet condi tions to the calorimeter were changed. Afterwards, the enthalpy differences were corrected to give enthalpy values using the base level as enthalpy of the saturated liquid at 75°F equal to zero. This was chosen as the base level beeause the liquid outlet temperature was always very close to the Freon-11 temperature in the 6 calorimeter, RESULTS The enthalpy of isopentane was successfully mea sured by this calorimeter and the experimental data on this compound were taken over the following ranges of temperature and pressures. Temperatures lif.O°F to lj.5>0°F Pressures 10 atm. to £0 atm. The corrected enthalpy data are presented in Table I and plotted in Figure 2. These data show a standard deviation of 2.9 Btu/lb. from the smoothed curves. The enthalpy values shown were corrected for a heat leak at the inlet to the calorimeter, k small amount of heat was transferred down the tube insulating the inlet hydrocarbon line causing the enthalpy value measured to be high for the value of inlet temperature measured. Since the effect of pressure on enthalpy at low pressures in regions not close to the critical can be calculated with good accuracy, the data at 10 atm., a relatively low pressure, were used to correct all the data for this heat leak. The enthalpy data were corrected to the desired pressure by first plotting the raw data as H vs. T and the isobars were drawn. Then, a cross plot of isotherms fit -> f i t m a E - t K FIGURE 2 THE ENTHALPY OF ISOPENTANE ■h-Q-for saturated liquid at 75 F 2. 00 * -TEMPERATURE 8 on an H vs. P diagram was prepared. The enthalpies were then corrected to the desired pressures by multiplying the slope H vs. P diagram by the difference in the desired pressure and the conditions under which the data point was taken. The temperatures were also corrected for the data taken in two phase region to correspond to the desired pressure. First, it was determined which data were in the two phase region from the H vs. T diagram. These data were then plotted as P vs. T and then the temperatures were corrected from the slope of this plot. These cor rected values were used in making the final H vs. T plot. In Figure 3, the smoothed correlation of the en thalpy data is compared to a similar correlation given by Maxwell (k) , which was corrected to the same base level. The agreement of these data and the Maxwell correlation is very good. The greatest deviations occur in the enthalpy of saturated liquid at temperatures within 15>°F of the critical point. The largest deviation of enthalpy is about 5 Btu/lb. for the saturated liquid at 3&0°F. This is a deviation of about 2|$. In Figure 4, the data in the two phase region are plotted and are compared to the data of Isaac, Li and Canjar (3) and data of Stull (5). These are the uncor rected pressure and temperature data for the two phase ENTHALPY Bty/lU : 4 ' : FIGURE 3 " - v . v ^ - ' COMPARISON OF 1 THESE DATA TO THE CORRELATION OF MAXWELL 200 IOO THESE DATA GO 200 100 vTEMPERATHRE-IF: PRESSURE . .PSIA foo 400 3oa .I F I G U R E 4 1 V A P O R P R ! ‘ 1 7 , \ ' ' > » 1 - i • r 5 5 S U R E O F v : 1 , -f r t - • H i -t" r ■ ■ ■i'-.i'1 .'!.,- C S O P E U T A U E ■ -j • < ; * < % . < ■ v . t * -1; * , r i . .q -p* ( r ... Q L—— p. * - / 1 ^ r - 7- 7 4 4 .- .:!• - 'J r . > ’ a ..... j < 1 0 . j _ „ I 1 _ ' “ ' T t * 4— 4 - - 4 * ...j.p — r 4 ► 4 ■ * * , * h . • j y -| '’ rS j .v :'. . • * i - 4 - ¥ \ r l > ♦ ? -» .• \ —± - 4 - j- J - U f i ! ■ • 1 i 1 u . r n i j : i 1 • i . i •)a. p !.. L 4 : . q ■r i-T ' > + - j-v-r • • - ^ ,s_. - < . 1'"/ T 4 'i t .t I ' I ■ .4 . . . ^..q. , r . . . . t-q.. q .:. •'! -h' , Tq l ; - n ^ ■ ...f - : ! - '--7 . , •- ! i f 9jP . : : 1 "; i ■ — - ;' -T — q ■ T f i b l i t ; 4 7 ' • • - ' 1 - • 4 . f - j.' ' J 1 ; . .jjc q .. L - i f v J*r4 ; t - j- u i- t . H i 1 j 1 J t i t j v r ' i ' i t t t r £ ■ > “ r ~r-j-i-'-f- j , ’ > f , f i t .■!-+•*;" ■ r r i 4 4 : 1 ‘ j. 1 sU- i r l ' h r i t t / -4 -r T f ■4-4 - r t - .f^U - - 4 - . .-:.Uk 7. 7 j q - » + , r ," . J 4 q - - f* - — 4 '- . - f c — — f • i i ■ ;• 7 '■ -;.. ,-j-. t r " i - - r -7'H -r-t- ■ : H 7 f : *1 > . - j- - ’- 1- | 1 *a_ ’ L 1 .; t j T * 1 "' ! 1 L ' ~~r"T“ \ ^ r ” 1 ■"* j h i T -j 1 " t h - h - i „ ,- f. ” * ^ -V ■ «P • '■ ■ ' j* H ‘ fy j :_ ■ r i r ' ■ ■ f t n r * i T i ‘ . ? . ! . -1 — p _ • “t. [ . f— *~ ;-r..h " • i i i t - t ! - H ~ r ! ; H ....’ -1 f 4 s ; p t { - y i; .L.; i j , f •! ; .t J I .! '< r/’I - . - M - . .4 .. q •- ;» x ; - f - t “ ■ f y - ; f t -• < » r ■ ■ H -t-r r l : b q . . J t- - .« .X -iR v.q-4..- f r r-1 - f 4 ^ - r 1 • * , . 4 - ■ h -s.-y- • :t | I ; — » » - < ■ * — f--- ' ' ' 1 _ . ... p . . » — f. ^ » .-l. ^ ............ q, 4 1 ! . .“ ••7 - » t- 1 . 4 • 1 V ' • - i f- * • J. V -r t1 • ? - : r * f ' * 1 -q -r - < | f ‘ i ' 1 * ■ * , t t - ■ <-. 4 4 - H ».t J .--* r-= 4 ' 7 7 ' 4 r ’ • i j -•< .••■ - i ', - r y { y - - y p i- { ■ ' I'.-f-j- j -j J .f-:- — y . ^ * , r ' r r ~ y • p / < f + 1 4 4 . .5 ™ t * u ; i P - ( • -j -q.-y. .+ - 4 . :.l- ( — >-4- t ! » ’ ) * • - t ■ ^ ...j . . ,...q --|.... ' I - ' f -! i -; * r q- - ; ■ j-4 -y;.- q i q 4 q ; p ; t ; : ± ; ' f 7 [ r : 7 : r .4- , . 1 .j...-c ,._p • i“T I . i .i. 1 { J t ; - t ~ ■ — ----! . n - — J .. i . — % p ^ r f < y q. . 1 4 | ■ * * J _ r _j 1 4 » I > j : • . • . • » • t — >-j— •> » •> -;4 7 '- - " r ■ • . r - , : - r v J . _ — 1 ' . . • : r .: — ■ t <-•••+-•!- - - r t - . ^ r j - j j i T r r ■v - j ; ; - S : J i i ■'F ' -•'t-'- j Tr-r- ' • - • • * - r - i- — t- ■ ■ (-"’ f X — ■ ! ' T ! \ y r i -{: !~ 1 / - l - f " / . 4...U . '■:r4~ ~y ' ’ " ; | 4 K x ... t . . . — — ..q ~ , U . i "4 t i T r r n 1 ^ " ‘r;, - f t t t t t . ' .: j...4 .J . + - _}. 4 -j-.| -,. -pr - j■ ~ q '• • • - ■ 'i" r < '•f-— " t -r» - 4 r-j ^..J. i • * ■ ■ ? ..... • • r - H '4 ' 4 “ ■ • * * • * * -*4,-4-- • — i - ■ ? ■ * < » - r * J - 4--+-4 7 ^.w j ‘ . 4^ 4— - :-;4: tj 4 + : l - f ' f ’ * _ r ^ 5 .4^ .-H .-f- - r ;:7;1"W 4 , - 4 '.7 T ‘( 'i 1 . r H , f ~ i !-► v ^7 .4 — ’ t 1 4 - t+ .- r 1 4 . • ; . . . 4 . - .*. 1 » , • - r ; * i •*- * r r-’ i ' f T . if’ *- I.- f * -. • - j., , : . . i.-.1 . t ,■ L. i 1 ' -*-f '* ~ i ± r t ? ± i ■ q j q i q . r t-j-r : - r W , i , L , A V ( . H " ' i > f Z ■ r '# : - i4 i - k ’f -A/ -1 - - /- 4 — . ./L .1 .J i\L .L * .L . ./» ■.»!»: , ^ i . r L p .L :4 ..4 X ..1 -4 4 4 -:-: - f * •** 4 -*+ •,— i:- — r - qr t i'1 n / f • 4 4 4 i. -L.J.-S ( i. 4 .. f . ...i .. i ^ 1 ’j" ' ■'"t ”4 -• 'r — ' 4 ^ .1 ’ -1 :» t .1 , * * . . ' 1 7 ■ q - - j u j ...- • * - » • - 4 — - • » • — f*» f-- * * , ■ • * .r:* t l ■ » — -...*....... • » '• '■ • "1 k * } * V • ■ • ' . ’■ > . . • • ■ • .t'.r; . ! • ^ i. 1 • • . • / ? ' r I H r ■ - r - 1 - ; ;. . } I . ’ ■ r , , ■ ■ ■ - i T H E S E - P i „ ; D A T A O F - i . D A T A - O F ^ . is J , i T A ' ' I S A A C , L I , Y O U N G 1 , ‘ ,"" J f 'f A N D C A N J i ■ ? f ■ > - K » « f ! * r 0 “ . i.:.* '.v \R & j : " - D J. ' ' l- C V .- - ' * 1 * v ' V .. 200 t o p .200 3oo ' , 4-Oo 11 region and are given in fable II. The lowest value of measured enthalpy reported is about i j . 0 Btu/lb. Some measurements of liquid enthalpies were taken at lower values, but these were very inconsist ent and were discarded. The lowest reliable enthalpy value that ean be measured by this calorimeter is about J j . 0 Btu/lb. DISCUSSION OP PARAMETERS AFFECTING CALORIMETER PERFORMANCE Three factors which have an appreciable effect on calorimeter performance are Freon-11 liquid level in the outer can, outer can heater duty, and the heat leak around the inlet to the calorimeter. These factors were not fully understood at the outset of this study. Subsequent measurements should have improved accuracy because liquid levels and heat duties can be controlled prior to measure ment. When the Freon-11 liquid in the outer can falls below a eertain level which is designated by normal as measured by a sight gage, the measured enthalpy values are low. The range of optimum Freon-11 level during oper ation of the calorimeter is between the normal and 2 inches above the normal level. When this level is below normal, the hydrocarbon condensing coil does not have sufficient submergence and the Freon-11 vapor formed is 12 superheated* The effect of this liquid level on measured enthalpy is shown in Figure j?. The data from which Figure $ was prepared is given in Table V in Appendix €. When the outer ean heater duty was above ©.£ watts for the periods of measurement, heat was transferred from the outer can heater through the Freon-11 in the outer can to the inner ean causing a high measured enthalpy value. The mechanism for this heat transfer is postulated to be natural convection caused by small temperature gradients. The effeet of the outer can heater duty on measured en thalpy is shown in Figure 6. Since nearly all the data reported were taken under conditions of appreciable outer can heater duty, a correction to the measured enthalpies had to be made. This correction is presented in Figure 7* The data from which Figures 6 and 7 were prepared are given in Table VI, Appendix £J. A heat leak exists around the inlet line to the inner can. At inlet temperatures above 320°F, appreciable heat was transferred to the inner ean from the fluid be fore it reached the thermocouple and the measured enthal pies were high. This was discovered by plotting the raw data and comparing it to the enthalpy calculated by values-of heat capacity at zero pressure. The enthalpy data at 10 atm. ^“^i nea -s'ured B‘ k ' u /lb; 13 FIGURE 5 EFFECT OF FREON-11 LIQUID LEVEL ■OEf'CALQRIKETER 'PERFORMNCE Isopentane, lOatm * t f 4-0 ■ 'i N 20 t - *4 - TV •+ - FREON-11 LIQUID LEVEL Hi- FIGURE 6 .O ■ ■ ' ■ © > r-4 S4 0 ra 014) •P < as S3 PQ , ; 4) rH S a s « . -;3 S3 4) t>» +» 4 ' . 41 Pt K M ISH +3 ca © . S 3 xi S3 © 4i m P i O ' S 3 : * S3 © W ' © S3 as. ’ U P © ©•6h a A-t w A-t *cj *rt S3 P OS EFFECT OF OUTER CAN HEATER ON CALORIMETER PER FORMS CE libpentanet 10 atm. 20 so o A i ^ , , ‘A " . \ L_- ----------- -------1. , :tr .1 " U a i n l e t T e m p . i j 3 8 0 ° F ° | : I , 1 2 7 0 ° F a I 2 0 0 ° F o 5*: i « T l ■ S / ' h ' - v ; " "X . i ^ V i - f - l '/ T - -fi*;. |* -4 - • * ■ - fcp * - U X ‘ 4 - i - t ' a— - I — *'- ' r > . _1 j, L j . - j- - • i - i ’ •- t ; iS S V . ;- ; 4- f* i- -p « |-t- K — — - * - f-f r * "*--.i — — • + S - - - ~ t_ f-i / X ‘ ' " - I i ~7“ 1 - . 5 ; . .i -L i r < - 4 1 4 *t i- S ■ i ■ ' ,N : ♦ ’ » r ^ ..u 4 - V -, » U ... i ' K t n x t ! i|.J ..> .4 |a ,.L 4 -.L : J,. ■.yt - ' ■ 4 4 ^ i -jl- 4 -4 J.: . ; ••4~fe4HV 1 ' 4 ' p - i - r ! -4 -+ -i + 4 - .j;. k :u :-4 ^ H i » -i -,, .( . ! :.f : i f r-i - . 'T T . p v r - l * .--p - ‘ .-4 ^ .... -4 « - 4 f |» * « - 4 « ^ / j y-{ -C r . f l S * f f e to - 7.0 3o Voltage to outer ean heater $ of 120v. 4© FIGURE 7 CORRECTION FOR THE EFFECT OF THE OUTER CAS HEATER ja S 3 t j 43 I ' ■ • f i f e - i I O i - j H 1 ) ■ E-f , i A -o ! ; K- ■ ' 1 K O I ° L Isoner.tane 2o / 5 f - V n i r 5 c . - * » > t f . 75i_ 1240 fefett, ■ - -4-. /-4 6: 10#)'y- V /O© 200 3 o o Measured Enthalpy Btu/lb ■ 4 - 0 0 15 pressure crossed the zero pressure line at reduced temper atures close to one. There is enough information reported in the literature to indicate that this is not correct* There were two possible explanations for this phenomenons 1. There was- some dntrainment of Freon-11 liquid in the vapor from the inner can. 2. There existed a heat leak around the hydro carbon inlet line. The data on the effect of liquid level on enthalpy indicate no trend of higher measured enthalpy value with higher liquid level. This discounts the first explanation of the above mentioned deviation. Since the enthalpy at low pressures and tempera tures higher than the critical ean be predicted with con fidence, predicted enthalpy values at 10 and 20 atm. were used to correct all the enthalpy data. The difference between experimental values and those predicted by Maxwell are shown in Figure 8. The correlation was used to cor rect all the enthalpy data presented. ACCURACY.OF THE MEASUREMENTS The following are errors that would affect the measured enthalpy valuest Temperature .05$ Pressure .2$ 5* <ri +3 « —I PP € > a J JS' « W 'o. -P Pk a M © 4 > M W t~l -w4 ■ $ is&if rrr: - • i-ii t - f H | T t, ij^ ^ ¥**- 4 r . -- ^ .4.1-,'f^ H W i t b -r~ *— *4 - “t- • » • — * —1 11 i - t ' « t ' 4 -H"' rr-H^rrt- n n v *-<■ <8 4 1 i_S- ! -r-j rp , 4 . i •ff.Tf-1 ------- s - JO + .- 00- p: ft-; ft 4 • H - f - : * t A* i 4 j * v l ;W - T f ■ & • &. - & J * FIGURE 8 HUT LEAK AROUND , HYDROCARBON INLET p- •£? i rH-.4 ** ) ~ < v r CD 4 - ’ -^<M- > H+7* °‘ r 4 f-* ? ■ — -t._l— f . < - > - » ■ V t - l- .i.ji...,, rOc — J . 4 ■ . X » - 4 * ■ - 4 — — -f » • * ■ * x. - m r -j-,. l , H-r J 4 1 Hiix: ti 10 atm. 20 atm. ( 7 . . ^ Y - T r f . P <w m r. .• & i S ^ - ■ J ? - 4 f7-sHr \ , tv*> T : . f • • * . • '■ > : ■ v * r . < j 4 jfii ,t „ < * * ..., < . < mp ■ t f e y r f 4 " ’ !y J t i^7fp ? 7 0 0 2oo 3oo 4 o e Temperature ®F H O' 17 Volume of Freon-11 .5$ Volume of Hydrocarbon The error in pressure would have negligible effect on the final result since the effect of pressure on en thalpy is small compared to that of temperature. The measured temperatures have a much higher precision than that required by accuracy of the enthalpy value itself. The greatest probable error exists in reading the levels in the Freon-11 and hydrocarbon receivers. Since the levels in both the hydrocarbon and Freon-11 receivers cannot be read simultaneously, a time lag is introduced. To eliminate the effect of this time lag the receivers are placed in close proximity and in a position such that the eye can move from one to the other quiekly. To minimize the effect of this time lag, these levels are always read in the same sequence. The magnitude of this error is about G.5>$ of the total measured enthalpy. From the above considerations it can be seen that the overall error in enthalpy should be in the order of !%• The individual data points show a probable error higher than this 1$ for three reasons: (1) The effect of Freon-11 liquid level was not understood until lately and this level was not accurately controlled. If this liquid level was too low some heat was removed from the inner ean by superheat in the Freon-11 18 vapor and the measured enthalpy was low. There is no way of telling if this occurred on any of the reported runs. (2) The outer ean heater also had an effect on the measured enthalpy. When this heat duty was above 12 Btti/hr. some heat was transferred into the inner can. This transfer occurred by natural eonvection caused by small temperature gradients. Although the heat duty of this heater was recorded on each run, the correction in evitably introduced some error. (3) The error in enthalpy introduced by heat leaks other than that around the inlet cannot be estimated but is assumed to be negligible because of the agreement of the data to that of Maxwell (If). The error in the correc tion for the heat leak around the hydrocarbon inlet is estimated to be 10$ but the error this introduces in the final enthalpy values is about 1$. The isopentane used in this study was obtained from Shell Chemical Company and was distilled to 99*5$ purity by C. P. Braun Research Laboratory. The major impurity in this material is neopentane. The effect of this impurity would have negligible effect on the results of this study because its physical properties are very close to those of isopentane. 19 CONCLUSIONS The enthalpy of isopentane has been successfully determined over an extensive range of temperature and pressure. The smoothed correlation is presented in Figure 2. This correlation is estimated to be within 0.£$> of the true values over its complete range. The agreement of the measured enthalpy values and those predicted by Maxwell fi^) for the region of the critical point is good and the maximum deviation of the smoothed data from that of Maxwell is about 2.$% for the enthalpy of the saturated liquid at a temperature near the critical. 20 Run Table I Corrected Enthalpy Data Isopentane 307 to to £7 362 to 32k 50 3 1 8 51 301}. £ 2 269 5to 257 5 5 1 2hS $(£ 2l|.7 57?- 2to 581 2£2 91 219 92 221 93 237 9fc 203 95 96 162: 97 15£ 98 125 1|.23 126 l j . 2 0 lto 179 l£6 lto 150 153 151 152 150 lto l£l 157 1 £ 2 159 lto 160 lto 161 178 162 182 164 211} . 1 Data in the two phase region | * r ^ n * « a r m * 1.(Btu/lb.) H smooth Diff. 2£l 2£7 -6 2£3 2to -5 2k6 2k9 -3 2 8l 280 1 280 2 81 -1 280 281 -1 250 2 5 8 -8 25£ 255 1 250 2£7 3 228 228 0 222 2 2 2 0 181} . 182 176 lil 88 91 3 92 90 2 99 101 -2 76 77 -1 7£ 75 -1 50 51 -1 to to -1 to to -1 325 320 5 320 3 1 8 2 63 6 2 1 50 to l £7 to 1 £7 it to: 3 £7 3 38 3 8 0 to 39 1 to to 0 to El -1 58 62 62 61}. -2 83 85 -2 2 L Table I (con’t.) Run Temp.°F H exp.(Btu/lb.) H smooth Diff. 215 olj. 85 -1 166 199 75 75 0 167 196 73 73 G 1 6 8 181 65 63 2 169 163 53 52 1 170 153 49 4 6 3 171, 149 45 43 2 1751 2 43 154 183 178 59 61 -2 184 27 0 227 228 -1 185 1 8 2 6 2 63 -1 186 1 8 2 63 63 0 187 1 8 2 6 2 63 -1 188 270 233 228 5 189 2 7 4 2 3 5 2 3 1 4 209 281 242 235 7 21 0 286 2 4 2 237 5 211 274 237 234 3 221 380 293 292 1 222 381 294 293 1 382 296 294 2: 275 239 231 8 225 276 2kl 2 3 2 9 226 207 81 80 1 227 2 0 4 7 8 78 0 235 200 77 75 2 236 200 77 75 2 237 200 77 75 2 238 4 2 7 3 23 323 0 239 4 2 2 319 319 0 427 321 323 -2 427 321 323 -2 243 430 324 325 -1 2i|4 429 321 324 -3 59 377 282 281 1 6 0 3 8 6 28 8 2 8? 1 6 1 3 8 4 287 286 1 63 352 265 264 1 344 258 259 -1 337 256 254 2 i Data in the two phase region Run 66} 67i 68} 70} 7 2} 73} 7^1 75 76 77 19 80 81 83 Qk ¥ 86 87 88 89 90 115 116 117 119 123 125. 163 10l} 1021 $ 1 106 107 1 08 109_ 1 1 0 1 120 1 2 1 122 22 Table I (con't.) np.°P H exp,(Btu/lb.) H smooth Diff. 314 226 3 1 1 229 313 227 311 21k 311 1 8 5 3 10 215 307 203 309 209 336 252 253 -1 33k 251 252 -1 31*4 255 259 -k 319 239 2i j .2 -3 317 237 2i j _0 -3 293 340 llj .1 -1 287 137 137 0 309 153 1 5 2 1 305 151 151 0 2 8 2 13^ 1 3 2 2 235 10 0 1 0 0 0 2 32 97 97 0 230 95 96 -1 365 27i|- 27k 0 3 6 8 279 275 k 322 2if.9 243 0 316 2kl 21a © W r 329 3 2 8 1 k39 323 323 0 23k 103 99 k 30 atm. pressure 353 210 355 231 3 60 2^6 2k$ 1 361 2k6 2I J .6 0 356 2k2 37k 263 261 2 3 82 269 269 0 385 2 72 2 7 2 0 3 80 265 267 -2 356 239 14-15 298 297 1 k32 310 310 0 if-59 327 328 1 1 Data In the two phase region 127} 128} 129} 13 Q1 131 132. 133 137 138 139 14 0 14 1 1 42 143 i I 176 177 178 180 181 182 23 Table I (con't.) Temp.°P fi exp.(Btu/lb.) H smooth Biff. 356 211 358 227 358 230 357 206 333 179 176 3 341 189 186 3 357 202 329 180 173 7 356 226 Bata in the two phase region 32.8 atm. pressure (critical pressure) 369 223 233 -10 369 240 2 3 3 7 369 233 233 0 383 251 261 -10 385 267 266 1 385 267 266 1 380 261 259 2 377 252 253 1 50 atm. pressure 370 202 203 -1 370 203 203 0 4 0 2 230 229 1 397 225 226 -1 345 183 182 1 344 180 181 -1 Run fable II Two Phase Data Isopentane T P P psia §? 21*4.9 147 56 21*4.9 143 245.2 147 §8 245.21 151 66 315.7 299 67 311.5 293 68 311.8 290 70 309.6 290 72 316.3 308 73 309.1 290 7!i 312.5 310 75 313.1 306 101 352.1 4 2 4 102 1 0 5 351.2 429 3A.8 449 110 3S7.8 445 127 360.6 457 128 356.2 435 129 356.2 435 130 360.0 4 5 0 133 352.2 425 1 3 4 3 6 6. 6 475 175 2 4 3 . 0 147 BIBLIOGRAPHY 1. API RESEARCH PROJECT i j J j . at the National Bureau of Standards, Physical and Thermodynamic Properties of Hydrocarbons and fcela¥ed Compounds, June 30, 1952. 2. Couch, H. T., The Performance and Progress in the Design of a Flow Calorimeter for the Determination of Enthalpy Changes in Liquids, Report on M.S. Research work, University of Southern California, 1961. 3. Isaac, Reginald, Kun Li, and L. I. Canjar, Ind. and Engr. Chem. Z j . 6, 199-201 (19$Z|-). l | . . Maxwell, J. B., Data Book on Hydro carbons, New York, 195>1* $. Stull, D. R., Ind. and Engr. Chem. J9, $17 (I9I 4.T) * 6. Young, S., Proe. Phys. Soc. (London) 13, 602, Cl892j.-9$). 7. Young, S., J. Chem. Soc. (London) Trans. 71» (1897)* 26 APPEND ICES 27 APPENDIX A EQUIPMENT a. Freon-11 Receiver (Figure 9) The vapor from the inner calorimeter flows up tub© A; it then flows into the reflux condenser, B. After it is condensed, either it is collected in the receiver, C, or allowed to flow back into the calorimeter via tube D. The maximum volume of Freon-11 that can be measured is 100 ml. This receiver was calibrated with distilled water. The data are given in Table III, and the correc tion to the read volume is given in Figure 10. Table III Calibration of the Freon-11 Receiver Run Calculated Volume ml. Volume Read Dlff 1 100.73 99.0 1.7 2 100.01 98.8 1.2 3 100.53 99.5 1.0 4 100.27 99.3 1.0 5 100.64 98.9 1.7 6 99.77 98.6 1.2 7 50.69 5 0 . 0 .7 8 50.61 5 0 . 0 •6 9 51.15 50.4 .8 10 5 0 . 6 8 5 0 .0 .7 11 75.68 74.9 .8 12 75.83 75.0 .8 13 75.79 74.6 1.2 14 75.54 74.6 .9 15 75.48 74.7 .8 28 29 FIGURE 9 FREON-11 RECEIVER A. Freon-11 Vapor Line (From the Inner Can) 3 . B. Reflux Condenser. C. 100 ml. Receiver 3). Liquid Return Line E. Stopcock "Correction tol* J$o he added to the volume read) % O M H O Q H> Pd c i Pd Pd Pd f e d f e d f e d o O ^ H td h o w O <j a § u> — o 31 b. Freon-11 Condensers The Freon-11 reflux condensers use ice water as the cooling media. There is one condenser which uses an acetone-dry ice bath; this is used to insure that all of the Freon-11 vaporized in the inner can is condensed. To condense the Freon-11 from the inner can, there is a six-inch reflux condenser which is part of the re ceiver, then above this, a twelve-inch reflux condenser, and finally, the dry ice-acetone condenser. c. Freon-11 Vapor Line Heater Previously, there was a heater which consisted of an electrically heated copper tube. Through this tube air was blown and then channeled to a box around the low J sections in the vapor line. This heater was used to keep i i Freon-11 vapor from condensing in the lower sections of the J ] vapor line, but was found to be inadequate and was removed.j i A 100-watt heater was installed around the tube. This j 1 heater consisted of 26 ga. nichrome wire wrapped directly j around the glass tube and was controlled by a variable j AO voltage supply. I i d. Outer Oan Heater | This heater is constructed of 26 ga. nicrhome wire j i wrapped around the outer can. To electrically insulate : this heater from the outer can, a thin sheet of asbestos • 3 2 is attached to the outer can with an adhesive. The maxi mum duty attainable with this heater is 21/.0 watts with 120 v AC voltage. This heater is controlled by a variable AC voltage supply. e. Pump A volumetric Hilton Roy pump is used to circulate the hydrocarbon. The output of this pump varies and the amount of hydrocarbon pumped has to be experimentally measured for any reliable enthalpy measurements. At times the hydrocarbon flow rate has been very erratic due to vapor binding in the pump. This vapor binding has been eliminated by cooling the feed to the pump with ice water. Valves have been installed upstream and downstream of the pump to prevent losses of hydrocarbon through the j packing when the pump is not in operation. These valves j also allow the pump to be removed from the system for work without draining the hydrocarbon from the system. j Caution: ; These valves must be opened before the pump is i started. i I It was found that carbon-like particles were being j circulated with the hydrocarbon. Upon dismantling the pump and examining it, the source of some of these par- i tides was determined to be the pump packing. ; 33 f. Hydrocarbon Heaters The hydrocarbon heaters were also a source of the particles, which were circulated with the hydrocarbon. Several times while operating, the pump would lose suction and stop pumping. This allowed these heaters to get very hot and the hydrocarbon in the heaters cracked forming carbon. This carbon is a catalyst for more decomposition and afterwards, this decomposition could take place at lower temperatures. Hew tubing was installed in the heat ers and their length increased from 3 to 6 feet. The new tubing eliminated the carbon catalyst and the greater length tended to eliminate any hot spots. g. Line Filter A filter was installed in the system to minimize the amounts of solids circulated with the hydrocarbon. This filter has three sintered stainless steel disks and a 1 0 ^mesh stainless steel screen. h. Hydrocarbon Receiver (Figure 11) This apparatus is used to measure the hydrocarbon flow during a run. The receiver consists of a 2l\.n by 3/kn heavy wall extruded glass pipe and adapters to the tubing. This tube was calibrated with distilled water using a calibrated 25 ml pipette. The calibration is given in Table IV. The volume in ml of the tube was found to be £ C B FIGURE II HYDROSARBOR RECEIVER A. Control Valve B* Metric Rule C. Glass Pipe Receiver D. Line From Throttling Valve !£ Lihe^To Pressure Gage F. Feed Boat e 35 2.540 L, where L is the length of the tu.be in era. The level in this tube is read on a metric rule placed behind the tube. The measure of the volume flow rate by this re ceiver is accomplished by: 1. Closing valve A. 2 . Recording the level in the receiver at a specified time. 3. Recording the level at some displaced time. if . . Opening valve A allowing the contents of the receiver to flow by gravity into the feed bomb. Table IV Calibration of Hydrocarbon Receiver Ho ter; A height of 4° cm indicates 0 volume Volume Height cm added ml Run 1 2 3* o 4 1 . 0 0 4 1 . 0 0 4 1 . 0 0 24.93 5 0 . 8 1 5 0 . 7 8 5 0 . 8 2 49.86 60.63 60.61 60.62 74.79 70.42 70.40 70.48 9 9 . 7 2 8 0 . 2 8 8 0 . 2 4 80 . 28 124.65 90.10 90.08 90.08 Tube was Inverted i. Throttling Valves Two needle valves were placed In the system to throttle the pressure. An Autoclave Engineers metering valve no. 30VR- 4 8 7 2 is used to take up the major portion 36 of the pressure drop necessary. It has an orifice of 1/16 inch and a needle with a 2° taper on micrometer threads. In series with this valve an Arrowsmith needle valve is used. This valve has an l/8, f orifice and is only used to adjust small pressure drops. j. Thermo coupl e s An Iron-constant an. thermocouple is used to measure the hydrocarbon inlet temperature. It has a stainless steel sheath and is placed in the s.s. tubing about ■I” above the top of the inner can. This thermocouple was calibrated at the boiling point of water and read, $.25?0 mv at 210.8°P. All other thermocouples used with this apparatus are copper-constantan* The hydrocarbon outlet tempera tures that were measured have been shown to be Incorrect because of bad thermocouple location. This thermocouple was relocated closer to the calorimeter outlet and the temperatures recorded were essentially the same as the Freon-11 temperature in the calorimeter. Therefore, the outlet temperature was taken as the temperature of saturated Freon-11 at barometric pressure. APPENDIX B PROCEDURES a. Calorimeter Start-up 1. Pill iee bath for Freon-11 condensers with ice and start cooling water circulation. 2. Remove stoppers on Freon-11 condensers. 3. Turn outer can heater to about Jj.0. Turn vapor line heater to .20. I j . . Wait until calorimeter and contents are at Freon-11 bubble point as shown by the outer can thermocouple. 5. Turn hydrocarbon heater to .0f>. 6. Fill ice baths around pump feed line. 7. Open valves upstream and downstream of pump. 8. Start pump. 9. After being sure pump is operating correctly and the system pressure is steady, turn hydro carbon heaters to the desired values. 10. Before the system is ready to take data, fill dry ice-acetone bath. b. Taking Data This procedure is given in the section on equipment and procedure in the text. Note? Before taking data __________________________________ ZL__________________________________ 30 1* Cheek lee bath for Freon-11 condensers. 2. Cheek reference junctions for the thermocouples. 3- Check ice bath on pump feed line. If . . Check dry ice-acetone bath. c. Calorimeter Shut-down 1. Turn off outer can heater. 2. Turn off hydrocarbon heaters. 3. Continue circulating the hydrocarbon until in let temperature is well below 15>0°F. Ij . . Shut off hydrocarbon pump. £. Shut off Freon-11 vapor line heater. 6. Close valves to hydrocarbon pump. 7. Close up Freon-11 openings to atmosphere. 8. Put the potentiometer away. 9. Shut off cooling water pump. 10. Drain ice baths. APPENDIX G MISCELLANEOUS DATA Table V The Effect of Freon-11 Liquid Level on Calorimeter Performance Data 10 atm* pressure Freon-11 H measured Run Inlet Temp.°F Liquid Level Btu/lb. 1 8 8 2 70 N 189 27k . N 235 190 278 N-lf inch 221 191 279 N-li 223 192 2 8l N-2| 1 80 193 2 8 1 N-2f 180 19& 27k N-2f 180 195 198 H-2* 52 196 19k N-2f 50 197 1 9 0 JT-1+ 58 198 18k N-l| 58 202: 181 N 61 238 k27 N+l-3/k 323 239 k22 N+l-3/i 316 2k0 k27 N+7/8 k27 2k3 k30 N 2kk k29 H 3 21 ^ . N-7/8 530 N-7/8 2k7 k26 N-l-3/k 279 2k8 k27 N-l-3/k 28k 39 Table VI The Effect of Outer Can Heater Duty on Measured Enthalpy Bata 10 atm. pressure Outer Can Heater Voltage jj Bun Inlet Temp.°P (% of 120 volts) measured 25 2513 201*. 271*. 25 271*. 206 2 7 7 1© 2I 4J 1. 27I 4- 1 0 2 38 2 0 8 275 10 280«. 0 0 2ij.2 211 271* . 0 237 212 253 40 21 *S 213 26k i*.0 271 l *-0 256 215? 378 2$ 309 216 375 25 307 217 37k 25 307 2 1 8 3 7 8 1 0 297 219 376 10 295 378 10 291*. 221 3 8O 0 381 0 291*. 223 3 8 1 0 297 228 200 25 90 229 201 25 91 201 25 90 200 10 81 233 200 10 79 231*. 198 10 77 235 199 0 77 236 200 0 77 237 200 0 77 a* Pressure Drop In Vapor Lines If there is appreciable pressure drop through the Freon-11 vapor line, the pressure in the inner can will be higher than that in the outer can. This will cause a temperature difference and heat to be transferred to the outer can from the inner ean. This pressure drop was calculated using standard equations for pressure drop in turbulent flow and was found to be negligible. b. Inerts in the Inner Gan Any inert in the inner gas in the inner can would tend to cause a heat leak to the outer can by raising the boiling point of Freon-11. IShen the calorimeter is started up, there is air in the vapor space of the inner ean. The time required to sweep this air out of the vapor space as calculated assume perfect mixing of this vapor and was found to be two minutes. This is negligible compared to the time required for the calorimeter to come to steady state. APPENDIX D ’ CALCULATIONS I. Calculation of enthalpy difference through the calorimeter A. Typical data sheet containst 1. System Isopentane 99.5+$ 2. Barometric pressure 760.8 mm Hg 3. Room temperature 68°F I f . . Run number 50 S. Inlet temper attire 317.6°F 6. System pressure 1 5 1 lb/in^ abs. 7. Volume of Freon-11 100 ml 8. Change in level in the hydrocarbon receiver during the determination 71.8-lf.3.2 cm 9. Outer ean heater setting Old heater .1,0 B. Properties of Freon-11 were taken from a bulletin, thermodynamic Properties of Freon-111 ’ Copyright 1936 by E. I. duPont de Nemours & Co. €. Required information 1. Freon-11 properties at barometric pressure a. Latent heat of vaporization 78.3 Btu/lb b. Liquid density l.lf.80 gm/ml 2. Hydrocarbon liquid density at room temperature and saturation pressure, Figure 12 .6200 gm/ce 10. D« Calculation 1* Correct Preon-11 volume using Figure 10, pg. 30 101.3 ml 2. Calculate hydrocarbon volume V = 2.5^0 L L - change in level em. 72 . 6 ml 3« Calculate AH . TT _ ? F-11VF-11 HV F-ll 1.^80(101.3)(78.31 /° hydro ^hydro (.620)(72.6) A H = 260.8 Btu/lb II. Correction of enthalpy A. Correct base level to 75°F 1* Outlet temperature = Freon-11 temp. 7£j ..7°F 2• Correction to enthalpy (Cp = 0.6 Btu/lb°F) -0.2 Btu/lb B. Correct enthalpy to base level saturation pressure of 1. Outlet pressure 151 lb/in2 2. Figure l l j . +0.3 Btu/lb C. Correction to correct pressure exactly 10 atm. to 1. (Figure n „ Btu in2 lbmlbL 2. Correction -0.8 Btu/lb D. Correction due to outer can heater Figure 7 -5.7 Btu/lb E. Correction due to heat leak at the inlet Figure 8 -0.8 Btu/lb F. Total correction -7.2 Btu/lb G. Corrected experimental enthalpy 2$l± Btu/lb III. Development of the effect of pressure on enthalpy at 7$°F 1. dH * * TdS + VdP Figure 12 (density vs* pressure) (Data obtained from Dr. Lenoir, University of Southern California) Figure 13 (volume vs. temp.) At 75>°F 2. dF » - SdT + VdP P 1 50 100 atm. i k$ FIGURE 12 DUSITY OF LIQUID ISOPEHTAHE o S' b f i >» -P •H CD S 3 © ( = » 0.67 0.66 0 . 6 5 " O.b4 0.63 0 . 6 2 . I O.&l 0.60 ' ■ t-'- r i ’T * " J* - ;•*. 1 - W-# > J -» ■ *• U * * » - i f » * * t * ** * ■ & - ' s - f 1 r • » • 1 ( ■ ■ * • * ■ ..' ' ' ; > ' * - !» ,£ t> 4 \ JrU • > **X |_ > - - ' i S X ■ ;^ 7 .H ; *.'/ ? > s . ' 1 * . 7 ^ 8 ^ « 1 > v r* • ■ • • • ■ “ *• • * r.4^r?s^'i .t r 'x - 1 t ^ , \ l s * T - , • 'i'A s^ A > • 1 ^ A w > 4 t f " - ^ ^ r v> t'i r - - r r 1 f l . ( • S - . - t r j t ■ i .. ! > f -r / - T f " * ' -%n » J "M ; ■•r.^u S X N ’ . N A. “ K V i ” • • — "t 1 • • ‘ -'— S ■ ■ *. '.'V ." . • \7, ^sL ■ ■ * - * t .,‘ v ■ .■ • '• ‘i.,'.> .■ ? j- k , * - -. fc ” s f • ; . , r ; / : ' " X I -*_L " " ' X - m . * ■ . -.- ■ * : i — ! > » • ' ^ - ‘ T 5 r f ^ Y ” j • • ' • ■ P t" * i ■ : * s --». •+.. 7 - . t » iJ ( ,. 1 - ■ » ~ , - • \ .v* 41 1 4_. ? s i. : * r \ ’ I ~ ' ! ,*« i * t *>*■ * • ; B x r ■ r r t f J ^ r )' t T - r - i - ~ L k - . • r : ’ -•':■*»• ! ' l . |.. L . . . — .. * 4 i.-^-.. - ~!~t '■ •♦ •*- ■ • ■ • • • * . J- •-+ - - * ' 4 n r i r - 8s > m . . . i. 4 ' ► •>S X " -‘^ 4- ■ ' *-"^.<81 # £ f e ‘ W ? H i , X - — 4 - - — - V ^ jIU * w * r ] , \ & Y * - : i t ‘ ’ • *rv* ^ * 5 * ■ . •A t: • 30 40 SO 60 ?© 90 9© 106 Temperature ®F Temperature k£> FIGURE IS SPECIFIC VOLUME OF ISOPEITME o I DO 9 0 8 o 7 O (,o So 4(7 1 . . . i . .. ...> - .<.. . .. ... 4 ' L ' *' ^ ^ * iTiljr i. ^ ■ 'l v - j*lf. '>*' tv « « M is.; F *3 • v y ' a / r r 6 — ^ V *4*^- “ 5---------------1 + V 1 L - . - :"S W Clr’i - - 1 ’ & / 1 ^ , < 7 * ; , '%’<& e tr/'/ • ,*>r. , £ / .*■'■ C i w ' * i j g f c . J ' > ' j *f 'it *& kL P t ’ ’ *_;■ . . . \ ‘ j / . : : - . i : - 0 " ? > - SrV- i H - > 7 " . ^ < i ■ A * A t , ’* * yx " ’ ' / * P ‘ - -. "fr<-V « % • / ; , 5r < j r f i i j / g % ' ■•*' S tV n r1 ' --------- f jt ' ■ \ ■ ■ f t . . * ' P - -i,4 * 'V 't - y - ■ ■ 1 * ' •'4 ' | ; '^r -»• f - {. vV 1 ■ * I . ’ i ; ■ * :? « ■ ■ :•• * ■ ' * . ■ • ■ • 'e ^ : ^3• • V'k-.'J : ■ ? ' 7 Y ~ u ? * y M M¥'~: ' ■ / - V * | V 1 *-{-•)- . . ' ' . ? 3 t » ■+“ •- ‘ 4 - £ k " t 3 r / .> ■ " T - l : , .... ■ * - T • « ■ — - +•-, ' r : t . . * •■ .+ " t ; * , V ' ' 5Z% t * . * * <• w i / ■- . i t 1 rSt- p f f t I f *»4r^.4 •••• r T 1 k *”* • • - 1 . . - • • • • ; - * 4-...* . • - + ■ - ; • --r - ! * 3 u , - A r ' f f ' •>. «>r!«SM nte - V ^ , ; 4 - - V v*r . "-.'•v. 4' LSI ,s+ ,Si> lfe l(’° />z A66 /.68 Specific Volume cc gm (4f)T mean = ^yjf), ® 1 atm + @ P^) A H = - O W S ^ i P H - Btu/lb. P - atm. - ec/gm Using /li) mean, Figure lk was constructed, ^ a F / <j> ■ IY. The development of the correction to correct enthalpy values to a desired pressures First, Figure 1$ (H vs. P) was prepared from a plot of the raw data similar to Figure 2. Figure 16 was then prepared from the slopes of Figure l£ and was used to correct the enthalpy data. kQ FIGURE 14 ENTHALPY vs PRESSURE LIQUID ISOPENTANE @ 75°F 5 * +> w >» Oi r -i A H t , « . - t - ; < /.i 1.0 0.8 0.6 r- rr M : ■tirt j j . “ 4 O.Z . 0 600 800 500 700 300 300 /OO Pressure psia Enthalpy Btvl"b 200 rSo ----------- r - ~ r - 'u —— PIGTJRE 15 ENTHiLPY PRESSURE DIAGRAM ISOPEEJAHE I Oo Soo 300 I oo f Pressure psia I 50 FIGURE 16 EFTHALPY eOFRECTIOR FOR SMALL PRESSURE LIFFEREFCES 1-0 0.8 0 . 7 -o U 0.4 •: - 0.3 0.1 4-zo 310 APPENDIX E RAW DATA Enthalpy Data on Isopentan© 99.5$ Data taken on I/I6/ 6 3 Barometric pressure - 760.8 mm Hg Room temperature - 68°P Outer can heater (400 watt heater) - 10$ Measured Volume of Hydrocarbon Vol. of Init. Final Run Inlet Pressure Freon-11 Level Level No. T,emp.°F >lb/ in^ ml cm cm Diff. k3 303.8 151 100 43.1 73.3 30.2 44 307.1 146 100 42.0 71.8 29.8 308 . l i _ 148 100 1* 4 . 1 73.7 2 9 . 6 46 360.5 147 100 4 3 . 5 69.3 25.8 47 362.1 147 100 4 2 . 2 68.1 25.9 48 361.8 147 100 4 2 . 2 68.1 25.9 49 3 2 4 . 5 150 100 4 2 . 8 70.8 28.0 50 317.6 151 100 43.2 71.8 2 8 .6 51 304.5 151 100 4 3 .9 73.0 29.1 52 2 6 9 . 1 146 100 4 2 . 0 73*9 31.9 53 2 6 0 . 0 147 100 4 0 . 7 73.0 32.3 54 256.6 147 100 4 2 . 7 75.6 32.9 55 2S4.9 147 100 43.6 83.3 39.5 56 21^.9 143 100 44*i 84.1 4 0 . 0 57 245.2 147 100 L6.0 87.2 4 1 . 2 58 245.2 151 9 0 ks- 3 91.5 46.2 51 52 Enthalpy Data on Isopentane 99.5$ Data taken on 1/1 8 / 6 3 Barometric pressure - 760.2 mm Hg Room temperature - 69°F Outer can heater (Jj.00 watt heater) - 10$ Measured Volume of Hydrocarbon Vol. of Init. Pinal Run Inlet Pressure Freon-11 Level Level No. Temp.°F lb/in2 ml em cm Diff. 69.3 25.7 67.3 25.1 69.3 2 5 . 2 69.1 27.4 70.2 28.3 70.4 28.5 76.9 32.1 75.3 31.7 75.5 32.0 59 377.3 6 0 386.3 61 384.4 63 351.9 6 i j. 3*1-3.5 65 336.8 66 315.7 67 311.5 68 311.8 29k 100 *1-3.6 298 100 *1.2.2 296 100 *l4.1 291 100 *1.1.7 296 100 *1-1.9 291|. 100 kl. 9 299 100 *14.8 293 100 *1-3.6 290 100 *1-3.5 51 Enthalpy Data on Isopentane 99.5$ Data taken on 2/1/63 Barometric pressure - 763-9 mm Hg Room temperature - 70°F Outer can heater (i}.00 watt heater) - Run N o. Inlet Pressure Temp. P lb/in^ Measured Volume of Hydrocarbon Vol. of Init. Pinal Freon-11 Level Level ml cm cm Diff. 51 Enthalpy Data on Isopentane 99.5^ Data taken on 2/li}/63 Barometric pressure - 7 6 0«9 mm Hg Room temperature - 73 °F Outer can heater (2^0 watt heater) - 25$ Measured Volume of Hydrocarbon Vol. of Init. Pinal Run Inlet Measure F r e o n . U Level Ho. Temp.°P lb/in2 ml cm cm Diff 77 79 309.1 290 312.5 31G 313.1 306 336.5 297 100 I (2.5 100 Jj.o.5 80 ij.1.6 100 l j . 1 . 0 100 ij.3.1 100 4 2 .0 55 Enthalpy Data In Isopentane 99.5$ Data taken on 2/20/63 Barometric pressure -'761.3 mm Hg Room temperature - 6 9°P Outer can heater (2I 4.O watt heater) - Run No. Inlet Measure Temp.°F lb/in2 Measured Vol. of Freon-11 ml Volume of Hydrocarbon Init. Final Level Level cm cm Diff. 80 3 1 8 . 6 304 100 81 317.4 3 0 2 100 293.0 2 9 6 100 8k 2 8 7 . 2 297 100 8? 3 0 9.I 295 100 86 3 0 5 . 0 2 9 6 100 87 2 8 2 . 2 296 90 88 235.0 3 0 0 65 89 2 3 2 . 0 300 65 90 2 3 0 . 0 2 9 8 70 91 2 1 9 . 1 I49 & 92 , 2 2 1 . 0 147 65 93 237*5 152 65 94 2 0 2 . 6 161 50 95 1 9 8 . 6 1 40 50 96 162.7 157 30 97 153.7 163 25 98 149.3 153 34 99 127.7 161 20 ij.1.8 4.1*6 to 4 4. 1.2 4 1 . 6 W - 2 # . 9 44.2 %L-k 51.0 k2.5 4 2 .ii So .9 8 3 42.9 71.3 71.3 9 1 . 2 93*0 85.6 87.1 88.1 88.3 89 . 6 87.6 88 . 7 85.6 82.9 86.1 80.2 82.8 9 2 . 2 80.1 % 56’ Enthalpy Bata In Isopentane 99.5$ Data taken on 3/20/63 Barometric pressure - 756*6 ram Hg loom temperature - ?3°F Outer can heater (21^0 watt heater) - 25$ 1 Run No* Inlet Temp.°P Pressure lb/in2 Measured Vol. of Preon-11 ml Volume Init. Level cm of Hydrocarbon Pinal Level cm Diff 101 352.1 k.2k 100 52.3 85.6 33.3 102 351.2 14-29 100 53.3 83.8 30.5 103 360.0 1(37 100 53.1 81.8 28.7 104 361.1 lf-37 100 534 82.1 28.7 105 35i4-.8 w 100 54.3 83.4 29.1 106 373.14- i(4i 100 53.1 79.9 26.8 10? 382.1 5- 3 14- 100 53.2 79.4 26.2 108 385.0 i(-32 100 53.1 79.0 25.9 109 379.5 445 IQO 52.4 79.0 26.6 110 357.8 445 100 53.3 82.8 29.5 57 Enthalpy Data on Isopentane 99*5$ Data taken on 3/21/63 Barometric pressure - 756.5 3 9 3 1 1 1 Hg Room temperature - 73°F Outer can heater (21+0 watt heater) - 25$ Measured Volume of Hydrocarbon Pressure Vol. of Inlt. Final Run Inlet Freon-11 Level Level No. Temp.°F lb/in ml cm cm Diff 115 36.50 289 100 1+1.7 6 7 . 6 25.9 116 367.5 389 100 1+0.9 66.3 117 3 2 2 . 0 285 100 l+t+. 1 72.1+ 28.3 119 315.8 289 100 14-3.2 7 2 .1+ 29.2 120 1+11+.8 kk$ 100 1+2*1+ 66.0 23.6 121 5-32.8 1+1+7 100 +2.5 65.1 22.6 122 1+59.1 W 100 1+1.9 63.2 21.3 123 1+1+7.2 296 100 1 4- 2.0 6 3 . 2 21.2 12k 14-39.3 293 100 kl.6 63.3 21.7 125 14-23*1 H 4-9 100 1+0.8 62.1+ 21.6 126 5.19.6 139 100 1+5-.9 66.9 22.0 58 Enthalpy Data on Isopentane 99.5$ Bata taken on 3/22/63 Barometric pressure -756.9 Hg Room temperature - 69°F Outer can heater (240 watt heater) - 25$ Measured Volume of Hydrocarbon Run Inlet Pressure Vol. of Freon-11 I nit. Level Final Level No. Temp.°F lb/in ml cm cm Biff. 127 360.6 457 100 46.8 79.9 33.1 128 356.2 435 100 47.1 78.0 30.9 129 356.2 435 100 46.4 77*0 30.6 130 360.0 450 100 46.4 80.3 33.9 131 333.0 433 100 43.9 82.6 38.7 132 3^0.8 454 100 43.7 80.6 36.9 133 352.2 425 100 43.9 78.3 134 329.ii- 447 100 43.6 82.2 i i i i f £9 Enthalpy Bata on Isopentane 99.5$ Data taken on 3/28/63 Barometric pressure - 757.2 mm Hg Room temperature - 67°F Outer can heater (2I 4.O watt heater) - 25$ Measured Volume of Hydrocarbon Vol. of Init. Pinal Run Inlet Pressure Freon-11 Level Level No. Temp.°P lb/in2 ml cm cm Diff. 42.6 73*6 31.0 52.8 73.9 31.1 41.9 56.k 14*5 {l.3 6I .0 20.5 44.6 60.8 l6.2 4 1 . 8 6 8 . 0 2 6 . 2 4. 2 .8 6 9 . 0 2 6 . 2 42.6 69.i|. 26.8 44-3 72.0 27.7 44*3 93.6 49.3 43*4 91.1 47*7 1 4 . 2 *3 91.6 I4.9 * 3 45.6 95.6 50 . 0 4-2.3 93.1 5 0 . 8 42.5 88.9 46*4 42.9 8 9 .8 46.9 44*9 89.9 44*6 136 3 6 6.6 475 100 137 369.1 485 100 138 369.4 486 50 139 36 8 .8 4§! 70 140 383.0 4 8 2 60 1 4 1 3 85.3 477 100 142 384.6 479 100 143 380.5 483 100 1 4 4 376.8 485 100 145 178.6 165 50 146 157.9 151 4 0 1 50 152.6 130 4 0 1 51 150.5 130 40 192 1 5 0 . 0 17 1 4 0 153 120.3 200 30 1 5 4 118.4 200 30 1 5 5 111.0 170 23 Enthalpy Bata on Isopentane 99.5$ Data taken on 3/29/63 Barometric pressure - 759*6 mm Hg Room temperature - 71°F Outer can heater (2I 4D watt heater) - 25$ Measured Volume of Hydrocarbon Vol. of Init. Pinal Run Inlet Pressure Freon-11 Level Level No. Temp.°F lb/in2 ml cm cm Biff. 156* D+0.8 208 25 42.5 93.1 50.6 157 * l42.4 218 25 43.6 92.1 48.5 159; : ; 1 4 4. 0 1) 4.7 25 43.1 89.2 46.1 160’; 3 4 5. 1 16 1 25 43.0 90.2 47.2 161* 1 7 7 . 7 169 40 43.3 94.® 51.5 162 181.9 169 41 4 2 . 4 92.6 5 0 .2 163 2 34.3 322 30 43.4 62.8 19.4 ' “ ‘ No appreciable heat transfer from outer to inner can. 61 Enthalpy Data on Isopentane 99. Data taken on 4/3/63 Barometric pressure - 761.5 ram Hg Room temperature - 76°P Outer can heater (240 watt heater) - 25$ Measured Volume of Hydrocarbon Vol. of Init. Pinal Run Inlet Pressure preon-11 Level Level No. Temp.°P lb/in2 ml cm cm Diff. i65^: 166 167* 168 169? 170? 171? 172.; 173? 17V' 175 214*4 207 50 i|4*2 89.9 45.7 215.i f . 217 51 45.1 90 . 7 45.6 199.3 213 50 4 2 . 7 93.1 5° .4 195.5 217 50 44.5 96 . 3 51.8 180.8 213 45 41«5 9 4 . 2 52.7 163.3 217 35 4 2 . 8 92*7 79.9 153.2 209 32 43.5 93.0 49.5 349.1 221 30 4 2 . 0 92.3 50.3 115.2 180 18 4 2 . 7 93.6 50.9 1 0 5 . 8 195 15.5 4 2 . 6 95.2 52.6 97.2 219 11 . 0 4 2 . 3 9 2 . 1 49.8 243.0 147 100 44*2 89.0 44.8 No appreciable heat transfer from outer to inner can. Inthalpy Bata on Isopentane 99.51$ Data taken on 4/4/63 Barometric pressure - 757*6 mm Hg Room temperature - 75°F Outer can heater (240 watt heater) - 25$ Run No. Inlet Temp.°F Pressure lb/in2 Measured Vol. of Freon-11 ml Volume Init. Level cm of Hydrocarbon Final Level cm Diff 176 370.5 740 100 43.8 78.3 34.5 177 370.5 735 100 42.7 77.1 34*4 178 ^01.6 732 100 45*2 75.6 30.4 180 397.1 737 100 47.1 78.1 31.0 1 8 1 345.3 736 100 43.8 82.1 38.3 182 344.4 737 100 44.8 83.6 3 8 . 8 63 Enthalpy Bata on Isopentane 99.5^ Bata taken on ij./l7/63 Barometric pressure - 755• 9 mm Hg Room temperature - 73°p Outer can heater (2^.0 watt heater) - 2£$ Measured Volume of Hydrocarbon Vol. of Init. Pinal Run Inlet Pressure Freon-11 Level Level No. Temp.°P lb/in2 ml cm cm Diff. 183* 178.5 270.2 # Y No appreciable heat transfer from outer to inner can. Effect of Freon-11 Liquid Level on Calorimeter Performance Data taken on 4/24/63 Barometric pressure - 756.5 mm Hg Hoorn temperature - 750^i , Outer can heater (2tf.O watt heater) - 2$% He as. Vol. of Hydrocarbon Pressure Freon-11 Vol. of Init. Final Run Inlet Liquid Freon-11 Level Level Ho. femp.°P lb/in2 Level ml cm em Diff. l8£ 1 8 1 . 8 Hj.8 H 40 43.9 92.7 92.7 186 182.2 lij.6 H 4-0 44»o 92.1 48.1 187 182.2 151 N 4 0 45.7 94.5 48.8 188 2 7 0 . 0 if|)| N 1 00 47.2 77.6 30.4 189 274*1 346 N 100 4 7 . 2 77.3 30.1 190 277.6 347 H-lf H-lf H-2§ H-2-g- H-2§ H-2§ 1 00 4 6 . 4 78.4 3 2 . 0 191 279.2 34 8 100 4 6 . 2 77.9 31.7 192 281*0 147 100 47.8 864 38.7 193 280.6 168 1 00 47.0 85.7 38.7 19if. 273.9 345 1 00 4 7 4 86.1 38.7 195 197.9 153 45 43.4 95.1 51.7 196 193.6 160 H-2§ 4 0 444 92.0 47.6 197 190.0 175 H-l§ H-l§ 45 4 2 . 9 90.8 47.9 198 184*2 190 45 4 4 . 1 91.8 47.7 199 182.0 168 H 47 434. 97.6 54.2 200 181.6 180 H 45 45.9 94*7 4 8 . 8 201 181.7 179 H 45 4 2 . 2 89.2 47.0 202 181.3 1 6 4 H 47 43.3 91.1 47.8 60 Effect of Freon-11 Liquid Level on ‘ Calorimeter Performance Data taken on 6/19/63 Barometric pressure - 706.6 mm Hg Room temperature - 78®F Outer can heater (250 watt heater) - 20$ Run No. Inlet Temp. °P Pressure lb/in2 Freon-11 Liquid Level Meas. Vol. of Freon-11 ml Vol. of Hydrocarbo] Init. Final Level Level cm cm Dif f 238 526.6 155 N+l-3/5 100 5 2 . 8 60.6 22.8 239 ij.21.6 101 N+1-3 / 5 100 53.8 66.9 23.1 2J+0 526.7 107 N+7/8 100 55*2 67.1 22.9 2l[2 526.8 109 N+3/5 100 05.6 77.6 23.0 253 530.0 105 N 100 02.3 75.9 22.6 2lih 529.3 100 N 100 03.7 76.6 22.9 2 50 529.2 100 n-7/8 100 03.3 77.6 25.3 2 I | . 6 530.5 130 N-7/8 100 61.0 8 5 . 8 23.8 m 526.5 162 N-l-3/5 100 61.6 87.8 26.2 258 527.3 161 N-1-3/5 100 62.8 88.6 20.8 I i 66 Effect of Outer Gan Heater on Calorimeter Performance (2 i { . 0 watt heater) Data taken on I+/25/63 Barometric pressure - 760 mm Hg Room temperature - 71*2°F Normal Freon-11 Liquid Level Run No. Inlet Temp.°F Pressure lb/in^ Outer Can Heater Me as. Vol. of Freon-11 ml Vol. of Hydrocarbon Init. Final Level Level cm cm Dif f. 203 276.3 li+3 .25 1 0 0 4 8 . 8 78.5 29.7 205. 2714-.2 1? ) i .25 100 4 8 . 8 78.7 29.9 20? 273.6 11+9 .25 100 W.5 78.5 30 . 0 206 2 76.6 11+5 .10 1 00 4 8 . 1 78.9 3 0 . 8 207 27k-2 llt .8 .10 100 1+7 . 8 79.3 31.5 208 275.0 11+3 .10 1 0 0 48.3 79.8 31.5 209 280.7 145 0 100 k7.6 78.7 31.1 210 285.5 141 0 1 00 47 .6 78.6 31.0 211 273.8 137 0 1 0 0 1+7.1+ 79.1 31.7 212 253.3 11+2 .40 1 0 0 77.2 30.5 213 26i J . . 5 11+2: .40 1 00 4 6 . 5 76 . 2 29.7 234 2 7 0. 6 l l | . l .40 1 0 0 +6 .9 7 6 . 2 29.3 i ! ! i 6? Effect of Outer Gan Heater on Calorimeter Performance (240 watt heater) Data taken on 5/l/63 Barometric pressure - 756.7 mm Hg Room temperature - 72.9°P Normal Preon-11‘Liquid Level Meas. Vol. of Hydrocarbon Outer Vol. of Init. Pinal Run Inlet Pressure Gan preon-11 Level Level No. Temp.°F lb/in2 Heater ml cm cm Diff. 21 5 377.8 216 375.3 217 374.0 218 377.8 219 376.2 220 375.6 221 380.5 222 380.7 223 3 8 1 . 6 145 .25 140 .25 1 42 .2$ 143 .10 1 4 4 .10 1 45 .10 147 0 143 0 139 0 1 0 0 4 4 . 6 100 4 3 . 8 1 00 4 3 . 7 1 0 0 43.4 1 00 43.0 1 0 0 4 4 . 2 1 00 4 3 . 8 1 0 0 4 2 . 9 1 0 0 4 3 . 7 68.6 2 4.O 68.0 2 4 . 2 67.9 24.2 6 8 . 4 2 5 . 0 68.1 2 5 . 1 69.4 25.2 69.1 25.3 68.1 2 5 . 2 6 8 .7 2 5 . 0 68 Effect of Outer Can Heater on Calorimeter Performance (21+0 watt heater) Data taken on 6/12/63 Barometric pressure - 752 Hg Room temperature - 75°? Normal Preon-11 Liquid Level Run Inlet i^essun ¥0 . Temp.°F lb/in 221+ 275.2 349 225 2 7 6.I 1 151 226 206.6 164 227 201+.5 177 228 200.3 161 229 2 0 0. 6 163 230 201.3 163 232 2004 163 233 199.9 1 61 235- 198.1 153 235 1994 159 236 199.6 I63 237 1 9 9 . 8 161 Me as. Outer Vol. of Can Preon-11 Heater ml 25 100 25 100 25 65 25 55 25 60 25 60 25 60 10 53 10 55 10 55 0 0 50 0 50 Vol. of Hydrocarbon Init. Pinal Level Level cm cm Dif f • 40.8 70 4 29.6 43.8 734 294 40.8 92.7 51.9 42.9 8 8 4 42.8 92.7 49.9 1+5.1 91+.8 1+9.7 43.7 93.6 1+9.9 14-5 93.7 49.2 1+2.2 94-6 524 1+2.3 91.3 49.0 43.7 92.7 1+9.0 I I untVERSlTY OF SOUTHERN CALIFORNIA LIBBA8 K

Linked assets

University of Southern California Dissertations and Theses

Conceptually similar

PDF

The phase behavior of cyclohexane-rich mixtures with water

PDF

A study of antiozonant additives for butyl rubber compounds

PDF

A study of the prediction of thermodynamic properties from recent equations of state

PDF

The study of the effectiveness of a screen to stifle diffusion flames

PDF

Prediction of viscosity of pure liquids, mixture of gases and mixture of liquids

PDF

Catalytic recovery of sulfur

PDF

Design, construction and operation of a flow calorimeter to measure enthalpies of mixed systems

PDF

Autoignition temperatures of hydrocarbon mixtures

PDF

A statistical study of the variables associated with the ozone cracking of elastomeric vulcanizates

PDF

Study of the flow properties of a thixotropic suspension

PDF

The Separation Of Multicomponent Mixtures In Thermally-Coupled Distillation Systems

PDF

Measurement of the enthalpy of n-pentane, n-octane, and n-pentane-n-octane mixtures

PDF

The tear resistance of elastomeric vulcanizates at elevated temperatures

PDF

An investigation of the corrosion of steel by sulfamic acid

PDF

Isothermal bulk modulus of liquids

PDF

Study of the parameters of rotameters with buoyant floats, for application to intravenous therapy

PDF

An experimental study of batch distillation

PDF

A study of the Lamb equation in dynamic systems

PDF

Ozone resistance of neoprene vulcanizates

PDF

Non-isothermal measurement of Ostwald-de Waele constants of various elastomers using a torque rheometer

Asset Metadata

Creator Stupin, Walter John (author)

Core Title The enthalpy of isopentane

Contributor Digitized by ProQuest (provenance)

Degree Master of Science

Degree Program Chemical Engineering

Publisher University of Southern California (original), University of Southern California. Libraries (digital)

Tag engineering, chemical,OAI-PMH Harvest

Language English

Advisor Lenoir, John M. (committee chair), Beeson, Carrol M. (committee member), Rebert, Charles J. (committee member)

Permanent Link (DOI) https://doi.org/10.25549/usctheses-c20-310995

Unique identifier UC11259078

Identifier EP41779.pdf (filename),usctheses-c20-310995 (legacy record id)

Legacy Identifier EP41779.pdf

Dmrecord 310995

Document Type Thesis

Rights Stupin, Walter John

Type texts

Source University of Southern California (contributing entity), University of Southern California Dissertations and Theses (collection)

Access Conditions The author retains rights to his/her dissertation, thesis or other graduate work according to U.S. copyright law. Electronic access is being provided by the USC Libraries in agreement with the au...

Repository Name University of Southern California Digital Library

Repository Location USC Digital Library, University of Southern California, University Park Campus, Los Angeles, California 90089, USA