NBSIR 88-3812

Working Fluid Selection for

Space-Based Two-Phase Heat

Transport Systems

Mark O. McLinden

U.S. DEPARTMENT OF COMMERCE

National Bureau of Standards

Gaithersburg, MD 20899

May 1988

Issued August 1988

75 Years Stimulating America's Progress 1913-1988 Prepared for: National Aeronautics and Space Administration

Goddard Space Flight Center

NBSIR 88-3812

WORKING FLUID SELECTION FOR

SPACE-BASED TWO-PHASE HEAT

TRANSPORT SYSTEMS

Mark O. McLinden

U.S. DEPARTMENT OF COMMERCE

National Bureau of Standards

Gaithersburg, MD 20899

May 1988

Issued August 1988

Prepared for: National Aeronautics and Space Administration

Goddard Space Flight Center

U.S. DEPARTMENT OF COMMERCE, C. William Verity, Secretary

NATIONAL BUREAU OF STANDARDS, Ernest Ambler, Director

ABSTRACT

The working fluid for externally-mounted, space-based two-phase heat

transport systems is considered. A sequence of screening criteria

involving freezing and critical point temperatures and latent heat of

vaporization and vapor density are applied to a data base of 860 fluids.

The thermal performance of the 52 fluids which pass this preliminary

screening are then ranked according to their impact on the weight of a

reference system. Upon considering other non-thermal criteria ( f lagimability

,

toxicity and chemical stability) a final set of 10 preferred fluids is

obtained. The effects of variations in system parameters is investigated

for these 10 fluids by means of a factorial design.

i
*

.

I

.
INTRODUCTION

In order to remove the heat generated by electronics and other

payloads on spacecraft some type of heat transport system is required.

The heat generating equipment is typically attached to a 'cold plate'. In

state-of-the art two-phase thermal control systems, these cold plates are

cooled by the evaporation of a volatile working fluid contained in closed

channels attached to the back of the cold plate. By using an evaporative

process to remove heat, the entire cold plate can be maintained at a

uniform temperature. The vaporized working fluid then flows to a condenser

where the latent heat of vaporization is rejected either to the main

spacecraft thermal loop or is radiated directly to space. The condensate

is then pumped either mechanically or by capillary forces back to the cold

plate to complete the loop.

The properties of the working fluid strongly influence the design and

performance of the entire heat transport system. Yet, to date there has

been no systematic and comprehensive evaluation of working fluids in these

systems

The working fluid in a two-phase heat transport system undergoes many

of the same processes and at roughly the same temperature as the refrigerant

in a vapor compression refrigeration system and will therefore possess

many of the same desirable properties. Several sources (e.g. [1],

[2]) present lists of desirable refrigerant properties; these are summarized

in Table 1. No single fluid satisfies all of the criteria presented in

Table 1, but through an evolutionary process extending over many decades a

few classes of fluids dominate present applications. Ammonia has excellent

thermal characteristics and is very inexpensive but operates at high

1
Table 1 - Desirable Properties of a Refrigerant

Chemical

Stable and inert

Health, Safety and Environmental

Nontoxic

Nonflammable

Does not destroy stratospheric ozone

Thermal

Critical point and boiling point temperatures appropriate for

the application

Low vapor heat capacity

Low viscosity

High thermal conductivity

Materials compatibility:

Soluble in lubricating oils

Compatible with common materials

Miscellaneous

Low freezing point

High dielectric strength of vapor

Easy leak detection

Low cost

2
pressures and is toxic. The hydrocarbons are also inexpensive and have

good thermal characteristics, are non- toxic but are flammable. The

hazards associated with ammonia and hydrocarbons limit their use to

industrial and large commercial systems. For smaller systems, the

halogenated hydrocarbons are almost universally used because of their

combination of very low toxicity and non-flammability. The tradeoffs,

however, are a higher cost, lower heat of vaporization, and generally

poorer transport properties.

The requirements of^a working fluid in a heat transport system are

somewhat different than those for a refrigeration system. In particular,

since the heat transport system does not have a compressor, the properties

that determine the behavior of a refrigerant in a compression process (e.g.

entropy) will be of lesser importance and a high heat of vaporization of

greater importance. For space-based systems the influence of fluid

properties on total system weight is a prime concern. This includes not

only the weight (density) of the fluid itself, but the required size and

strength of the heat exchangers and piping, and a factor to account for the

pump work necessary to circulate the fluid. For capillary-pumped systems

a high surface tension is desirable.

As with terrestrial refrigeration systems, the safety-related

characteristics of toxicity and flammability are of concern. The intended

application will determine the relative importance of safety and thermal

characteristics. The present study focuses on unmanned systems and thus a

toxic and/or flammable fluid cannot be automatically eliminated. For

manned spacecraft applications, the ranking criteria, and thus conclusions

regarding the best fluid, may be entirely different.

3
For these reasons it is worthwhile to undertake a comprehensive

evaluation of working fluids in heat transport systems rather than merely

choosing a fluid based on refrigeration system criteria. The purpose of

the present work is to establish criteria for the evaluation of potential

working fluids for a specific class of space-based systems, apply these

criteria to a large number of fluids to select the best fluid(s) , and

present the tradeoffs existing among these best fluids. This will then

enable NASA designers to make a rational choice of working fluid for

future systems. While focusing on space-based systems, the analysis

presented here is applicable to ground-based systems as well.

The general approach will be to apply a series of screening criteria

to the fluids contained in an extensive data base. As the number of

fluids passing each successive set of criteria is reduced, the subsequent

criteria will be increasingly sophisticated. The Physical Property Data

Service (PPDS) data base of 860 industrially important fluids will be

used. This proprietary data base has been compiled by the Institution of

Chemical Engineers in the United Kingdom. NBS has purchased this data

base in the form of an ' Electronic Data Module' which is connected to a host

microcomputer. While no data base can contain all possible fluids, the

PPDS data base contains representatives of every major class of fluid; as

will be seen later, it is particularly complete for the types of fluids

which are highly ranked in the analysis. (A more detailed description of

this data base, including a listing of the 860 fluids, is given in

Appendix I .

)

Those fluids passing a set of preliminary criteria will then be

evaluated in a reference heat transport system. The fluids will be ranked

4
according to a system weight which includes the fluid weight, the fluiddependent portion of the component weights and an allowance for pumping

power. At this point the ranking of the fluids will then be considered along

with other, non-thermal, properties such as stability, toxicity, flammability

and materials compatibility to arrive at a final set of preferred working

fluids. Finally, the effects of changes in the parameters defining the

reference heat transport system will be analyzed for the final set of

fluids by means of a factorial design.

5
REFERENCE HEAT TRANSPORT SYSTEM

Proposed designs for next-generation spacecraft heat transport system

are rather complex with numerous sensors, automatic valves, controllers,

etc. Figure 1 depicts one proposed design for a Space Station attached

payload active thermal control system. A very detailed design and

analysis program has been developed for this system by Costello [3]. This

program is currently limited to ammonia and Rll but could, in principle,

be extended to other fluids.

But rather than analyze the effects of different fluids on a very

specific system, the approach taken here is to reduce the heat transport

system to its essential elements. The selection of the working fluid

would be made early in the design process; details of the design would

vary from fluid to fluid. Thus, consideration of a simplified, generic

system is called for. Furthermore, the analysis is limited to those

portions of the system which are fluid-dependent. For example, while the

flow channels attached to a cold plate may vary in size or pressure rating

according to the working fluid the actual cold plate itself will be

independent of fluid. Similarly, a particular sensor or automatic valve

will be required independent of the fluid. This sort of approach not only

greatly simplifies the analysis but also generalizes the results. The

system is specified in terms of a limited number of parameters which can

easily be varied to examine different design parameters.

This study will consider two systems - mechanically-pumped and

capillary. The reference pumped system is shown in Figure 2. The evaporator

is taken to be 4 cold plates piped in parallel. Each cold plate has 5

parallel flow channels for a total of 20. Each channel is 0.76 m long and

6
Figure 1 - Schematic of typical attached payload active thermal control system.

7
Figure 2 - Reference (base case) heat transport system, mechanically pumped.

8
consists of a 9.5 mm diameter liquid channel and a 25 mm vapor channel.

The design heat load is 10 kW. The condenser consists of 8 parallel,

1.22 m long annuli with an inner and outer diameter of 20 and 25 mm

respectively. Connecting the evaporators and condenser are liquid and

vapor lines, each 30 m in length; the diameters and wall thickness of

these lines will be optimized for each fluid subject to a maximum diameter

of 38 mm and minimum wall thickness of 0.8 mm.

The accumulator is designed to store the entire fluid charge as

liquid. Its volume is 1.2 times the total fluid volume of all the other

components. This large accumulator volume represents a very conservative

design approach which has significant weight implications. It is used

here as representative of the current state-of-the-art. The circulating pump

is specified in terms of an equivalent weight of 0.25 kilograms per watt

of theoretical pump work. This factor includes the pump efficiency, the

weight of the pump and an allowance for the weight of the power system

necessary to supply the pump.

The nominal and maximum operating temperatures are 20° C and 45° C,

respectively. The system would be expected to survive without damage from -

40° C to 80° C. The upper temperature limit may impose a significant

penalty on some fluids since the system must be designed for the fluid

vapor pressure at 80°C.

For capillary systems (Figure 3) the circulating pump is replaced by

a wick assembly which 'pumps' the fluid through capillary forces. An

effective pore diameter of 10/im is assumed for the wick. The design heat

9
load is 2 kW for the single cold plate. The size of the condenser is also

proportionally smaller compared to that in the 10 kW mechanically-pumped

system. In all other aspects the capillary and pumped systems are identical.

10
Figure 3 - Reference heat transport system - capillary.

11
FLUID EVALUATION PROCEDURE

A suitable working fluid must satisfy many requirements. Of primary

concern is its long-term chemical stability. The relative importance of

good thermal performance, low toxicity and non-flammability depend on the

application. For systems which serve inhabited spaces, safety considerations

would take precedence over thermal performance. For systems which would

serve externally mounted equipment or experiments, a fluid of at least

moderate toxicity and/or flammability might be chosen if it had superior

thermal characteristics (as indicated by the present use of ammonia in

some systems) . Of secondary importance would be such criteria as materials

compatibility, cost and availability. One would approach the problem of

fluid evaluation according to relative importance of the various requirements

and also according to the resources available.

In the present work, the focus is on thermal performance. This arises

not only from the goals set forth at the outset of the project but also

from the relative ease of evaluating thermal performance. The availability

of a computerized data base for thermodynamic and transport (but not e.g.

toxicological) properties makes it more efficient to evaluate the chemical

stability, toxicity, flammability, materials compatibility, etc. of those

fluids which pass the thermal criteria rather than vice-versa.

Preliminary Screening

The PPDS data base contains information on 860 materials, many of

which are solids or super-critical fluids at normal temperatures. The

first screening criteria, therefore, will select only those materials

which have coexisting liquid and vapor phases in the temperature range of

12
interest, specifically a freezing temperature less than -40° C and a

critical temperature greater than 50° C. The cutoff for critical temperature

is 5°C above the maximum operating temperature.

An additional requirement is a vapor pressure of no more than

5000 kPa at the highest temperature the system is expected to survive

(80°C). For fluids with critical temperatures between 50°C and 80°C this

last criterion is for a critical pressure less than 5000 kPa. The vapor

pressure criterion was selected on the basis that fluids operating at pressures

substantially above those for ammonia (857 kPa at 20°C, 4129 kPa at 80°C)

would not be acceptable.

Of the 860 fluids, 513 pass this first set of criteria. These 513

fluids were then screened according to their ability to remove heat by

evaporation as measured by the product of the latent heat of vaporization

and the saturated vapor density evaluated at 25° C. This parameter is a

measure of the vapor volumetric flow necessary to remove a quantity of

heat which in turn has a strong influence on required piping sizes,

pressure drops, etc. A minimum value of 1.0 kJ/L, or about one order of

magnitude lower than the value for ammonia, was selected. The application

of this criterion reduces the list of fluids to 51. Eliminated were those

fluids which would operate at very low vapor densities and would therefore

require excessively large vapor ducts.

Upon examining the fluids which failed, only two - HBr and CH2 F2

- were

eliminated on the basis of excessive vapor pressure. HBr can reasonably

be excluded because of its extreme toxicity and reactivity. Since the

cut-off value for pressure was somewhat arbitrary, there would seem to be

little reason to exclude only a single compound on the basis of vapor

13
pressure and thus CH2 F2 was re-added to the list. Water failed the

freezing point criteria but has the highest heat of vaporization of any

fluid and was therefore also added. The vapor pressure data for C0C1 2 (phosgene) in the data bank were seriously in error and would have

required special treatment; in view of its extreme toxicity it was deleted

from the list. These additions and deletions yield a list of 52 fluids,

given in Table 2, which will be considered in greater detail.

Ranking By Incremental System Weight

For the ranking of thermal performance, a single figure-of -merit is

desirable. For terrestrial thermal systems, total life cycle cost is an

excellent index. Given the high cost of placing mass in orbit, system

weight is the most appropriate index for space-based systems. The 52

fluids which passed the preliminary screening are evaluated in the

reference heat transport systems with the resulting incremental system

weight serving as a rating factor. This rating factor is a measure of the

differences in system weight between fluids; it does not represent the

total weight of the heat transport system. This weight is composed of

four terms which will vary from fluid to fluid: the piping weight which

is a function of its diameter and wall thickness; the fluid weight which

is a function of the fluid density and total system volume; the accumulator

weight which depends on system volume and operating pressure; and (for

pumped systems) the equivalent weight associated with the pumping power.

Heat Transfer Considerations

The operation of the two-phase heat transport system involves the

14
Table 2 - Summary of Fluids Passing Preliminary Screening

PPDS Name ond formula Tme 1 t Tc r i t VP025 VPO80 Hf g/Vv

No (K) (K) (kPa) (kPa) (kJ/l)

HYDROCARBONS

6 1 ,2-BUTADIENE C4H6 137. 444 168. 802. 1 .62

7 BUTA-1 ,3-DIENE C4H6 127. 425. 281 . 1151. 2.55

8 BUTANE C4H10 135. 425. 244 . 1015. 2.20

9 BUT-1-ENE C4H8 88 420 297. 1201 . 2.57

10 2—BUTENE(CI S) C4H8 134 436. 214. 928. 2.03

1 1 2—BUTENE (TRANS) C4H8 168. 429. 234. 996. 2.18

12 1-BUTYNE C4H6 147. 464 188. 842. 1 .22

48 ISOBUTANE C4H10 113. 408. 350. 1335. 2 98

49 2—METHY LPROPENE C4H8 133. 418. 304. 1196. 2.68

57 PROPANE C3H8 85. 370. 950. 3136. 6.95

58 PROPENE C3H6 88 365. 1155. 3719. 8 19

60 PROPYNE C3H4 171 . 402. 577. 2244. 4.95

66 ALLENE C3H4 137. 394 805. 2779. 5.36

170 VINYL ACETYLENE C4H4 * • * • 455. 202. 855. 1 .97

313 3—METHYLBUT-1-ENE C5H10 105. 453. 120. 566. 1 .15

HALOCARBONS , 130 VINYL CHLORIDE C2H3CL 119. 425. 389. 1485. 3.18

177 CHLOROETHANE( 1 60) C2H5CL 137. 460. 160. 751 . 1 .61

21 1 2—CHLOROPROPENE C3H5CL 136. 478. 110. 551 . 1 .18

355 CHLOROMETHANE ( 40

)

CH3CL 175. 416. 570. 2156. 4 88

369 CHLORODI FLUOROMETHANE CHCLF2 127. 369. 1041 . 3648. 7.97

431 D I CH LOROD I F LUOROMETHA CCL2F2 115. 385. 651 . 2291 . 5.13

432 BROMOCHLORODI FLUOROME CBRCLF2 113. 427. 275. 1128. 2.49

434 DICHLOROFLUOROMETHANE CHCL2F 138. 452. 182. 853. 1 .83

435 1 , 2-DICHLORO-1 ,1,2,2- C2CL2F4 179. 419. 212. 929. 2.00

436 chloropentafluoroetha C2CLF5 174. 353. 916. 3150. 6.89

439 1—CHLORO—2 . 2 . 2-TRI FLU C2H2CLF3 168. 429. 199. 947. 2.18

440 TR I CHLOROF LUOROMETHAN CCL3F 162. 471 . 107. 527. 1 .12

482 BROMOTR I FLUOROMETHANE CBRF3 105. 340. 1614. 3965. 10.83

483 D I BROMOD I FLUOROMETHAN CBR2F2 132. 471 . 110. 545. 1 .20

485 D I FLUOROMETHANE (32) CH2F2 137. 352. 1689. 5816. 11.92

486 BROMOMETHANE CH3BR 180. 464. 218. 971 . 2.14

487 1 . 1-DICHLORO— 1 ,2,2,2- C2CL2F4 216. 419 . 218. 940. 2.10

490 1 -CHLORO-1 , 1 —D I FLUORO C2H3CLF2 142. 410. 354. 1441 . 3.22

492 1 , 1-D I FLUOROETHANE( 1C2H4F2 156. 387. 607. 2328. 5.12

649 VINYL BROMIDE C2H3BR 135. 474. 141 . 621 . 1 .39

C + IH + 0 COMPOUNDS

64 ACETALDEHYDE C2H40 150. 461 . 118. 608. 1 .29

1 1 1 METHYL ETHER C2H60 132. 400. 593. 2224. 5.00

143 formaldehyde CH20 181 . 410. 533. 2318. 4.85

193 ETHYLENE OXIDE(EPOXYE C2H40 161 . 469. 175. 872. 1 .80

196 KETENE C2H20 139. 373. 1293. 3983. 9.73

NITROGEN COMPOUNDS

70 AMMONIA NH3 195. 405. 1003. 4141 . 8.88

216 TRIMETHYLAMINE C3H9N 156. 433. 219. 941 . 2.06

422 ETHYLAMINE C2H7N 192. 456. 141 . 768. 1 .63

423 DIMETHYLAMINE C2H7N 181 . 438. 205. 1016. 2.17

554 METHYLAMINE CH5N 180. 430. 348. 1655. 3.55

SULFUR COMPOUNDS

228 SULPHUR DIOXIDE S02 198. 431 . 396. 181 1 . 3.88

373 METHANETHIOL CH4S 150. 469. 202. 937. 2.01

375 CARBONYL SULPHIDE COS 134. 375. 1245. 4000. 8.82

MISCELLANEOUS COMPOUNDS

63 WATER H20 273. 647. 3. 47. .06

154 CHLORINE CL2 172. 417. 778. 2737. 6.24

380 HYDROGEN IODIDE HI 222. 424. 788. 2668. 6.31

467 BORON TRICHLORIDE BCL3 166. 452. 155. 702. 1 .53

15
transfer of heat to and from the working fluid in the cold plate and

condenser, respectively. This suggests that the varying heat transfer

coefficients among the candidate fluids would have a significant impact on

system design. Somewhat surprisingly, however, it will be seen that the

application, reference system design, and fluid properties combine to yield

very similar heat transfer performance among the 52 fluids considered in

detail

Evaporative heat transfer coefficients are most often correlated in

terms of separate nucleate and convective contributions; an example is the

correlation by Chen [4]

hsvap = S tVu, + F hlQ (1)

where the coefficients obtained from nucleate boiling, h^ b , and single

phase convective, hi

, correlations are multiplied by a suppression factor

(S < 1) and two-phase multiplier (F > 1) respectively to obtain the twophase coefficient. For conditions of low heat flux (such as the value of

8.4 kw/m2 for the reference system) and/or high vapor quality, nucleate

boiling is completely suppressed so that:

h

„„ = ( 2 )

The value of hi 0 is given by a single-phase correlation such as Dittus -Boelter

k,

r (l - x) m)' 0 . 8 fr

, i

D DMi N V

44

o . 4 (3)

where x is vapor quality and ki and /i i are the thermal conductivity and

viscosity of the liquid. A widely-used correlation for the two-phase

multiplier is that by Chen [4]

16
F = 1.0 + 1.8

1 -x

0 . 9 f > Pv0 . 5

r y Pi

O

1

.Pi. J

0.82

(4)

The combination of equations (3) and (4) for a given mass flow rate, pipe

diameter and quality and the assumption that the constant 1.0 in Equation

(4) is small compared to the second term yields the dependence of evaporative

heat transfer coefficient on fluid properties:

h _ f/i.0.6 -0.482 , 0.082 r 0.4 .0.41 _ -0.41\

“evap ~ » 4V >

, i » Pi * Pv ) (5)

To remove a given quantity of heat, the mass flow rate is inversely

proportional to the heat of vaporization:

h — ffh "0.8 uO . 6 - 0.4 82 ., 0.0 82 n u . n ne v a p “ r v nfg » Ki > Mi » 4V * ^p , i > Pi * Pv

0.4 „0 . 41 °' u ) ( 6 )

For condensation, the correlation of Shah [5] gives the average heat

transfer coefficient for complete condensation of a wide variety of

fluids

hcond = hJo (0.55 + 2.09 P/ 0 - 88

) (7)

where Pr is the reduced pressure and hi 0 is given by Equation (3). For a

given mass flow rate and diameter:

h — f • 6 // "0.4 n 0.4 p

- 0 . 3 8 \ ncond “ ' t*i ' Upl * rr )

Again, to remove a given quantity of heat:

h — fYVi "0-8 u0 . 6 ., -0.4 p

0 . 4 p

-0 . 38\ ncond “ r ^ nfg » Ki » Pi * Upi * r r )

( 8 )

(9)

The properties groups given in Equations (5, 6, 8 and 9) are presented

in Table 3 for the 52 fluids passing the preliminary screening. (The

numerical values presented in Table 3 were evaluated at 20°C and have been

17
Table 3 - Comparison of two-phase heat transfer coefficients as given

Equations 5 , 6 . 8 and 9 for the cases of equal mass flow ra and equal heat load.

PPDS Formula hf g m = const Q_= const

NO. (kj/kg) ^evip hc 0 n d v a1 p hc 0 n < HYDROCARBONS

6 c*h6 433.5 .410 .422 .916 .944

7 c„h6 387.9 .340 .364 .831 . 888

8 ^4 ^1 0 359.5 .301 .329 .781 .855

9 c*h8 354.6 .299 .327 .784 .859

10 c a h0 398.8 . 340 .363 .813 .866

11 c,h8 386.3 .320 .342 .783 .838

12 c*h6 441.1 .493 .440 1.087 .970

48 CaH 10 331.7 .244 .276 .676 .765

49 c,h8 360.6 .279 .306 .722 .792

57 C 3 H8 344.9 .211 .249 .565 .669

58 C3 H6 344.5 .220 .261 .590 .701

60 c3 h4 481 .

.301 .330 .618 .677

66 c 3 h4 434.8 .289 .298 .643 .664

170 C*H4 443.3 .366 .401 .802 .881

313 C 5 H: o 323.6 .340 .369 .960 1.041

HALOCARBONS

*

130 C2 H3 C1 300.5 .247 .260 .741 .778

177 c2 h5 ci 372.1 .311 .326 .785 .823

211 c 3 h5 ci 326.4 .304 .333 .853 .934

355 ch3 ci 386.0 .292 .314 .716 .771

369 chcif2 185.9 .126 .146 .553 .640

431 cci2 f2 141.2 .099 .115 .541 .629

432 CBrClF2 127.1 .103 .114 .614 .681

434 CHC12 F 232.6 .196 .212 .722 .779

435 ^2 Cl 2 128.3 .106 .121 .630 .714

436 C2 C1F5 97.4 .073 .091 .541 .671

439 c2 h2 cif3 203.0 .147 .163 .604 .670

440 CC1 3 F 183.5 .169 .186 .749 .828

482 CBrF3 84.0 .061 .078- .510 .649

483 CBr2 F2 125.1 .126 .139 .762 .842

485 ch2 f2 272.2 .189 .211 .613 .684

486 CH3 Br 247.1 .192 .200 .673 .700

487 C2 CI2 ^4 130.4 .094 .109 .549 .634

490 c2 h3 cif2 206.8 .132 .151 .534 .609

492 c2 h, f2 280.8 .203 .219 .643 .692

649 C2 H3 Br 220.6 .228 .224 .873 .860

C + H + O COMPOUNDS

64 C2 H4 0 593.9 .608 .538 1.055 .934

111 c2 h6 o 409.2 .325 .355 .760 .831

143 ch2 o 695.0 .553 .513 .847 .786

193 c2 h,o 561.4 .507 .518 .921 .941

196 c2 h2 o 383.6 .232 .249 .573 .614

NITROGEN COMPOUNDS

70 nh3 1184.5 1.000 1.000 1.000 1.000

216 c 3 h9 n 372.9 .319 .347 .805 .874

422 c2 h7 n 622.2 .572 .596 .958 .998

423 c2 h7 n 561.1 .468 .482 .851 .877

554 ch5 n 772.9 .583 .595 .820 .837

SULFUR COMPOUNDS

228 so2 359.7 .304 .324 .790 .840

373 CH,S 496.4 .449 .474 .899 .950

375 COS 244.0 .196 .222 .693 .788

MISCELLANEOUS COMPOUNDS

63 h2 o 2454.5 5.891 5.570 3.288 3.110

154 Cl, 255.0 . 146 .170 .498 .580

380 HI 141.3 .035 .043 .191 .238

467 BC1 3 199.6 . 198 .205 .823 .853

Note : Heat transfer coefficients are relative to the values for amraoi

18
normalized relative to ammonia.) The individual fluid properties of

conductivity or viscosity vary by as much as an order of magnitude among

the various fluids and likewise the two-phase heat transfer coefficients

vary over a wide range when considered on the basis of equal mass flow

rate

When considered on the basis of removing a given quantity of heat,

the differences in heat transfer among the various fluids is greatly

reduced. Excluding those compounds in the "miscellaneous" category, for

the equal heat case, the maximum variation among evaporative coefficients

is 2.1:1 and only 1.7:1 among condensation coefficients compared to 16.3:1

and 12.8:1, respectively, for the equal mass flow rate case. Fluids, such

as Halon 1301, which have low conductivities and heat capacities, (properties

which lead to poor heat transfer coefficients) also tend to have low latent

heats. In order to remove a given quantity of heat with such a fluid, the

mass flow rate must be much higher than with a fluid with a high latent

heat, such as ammonia. The higher mass flow rate implies increased velocities

and Reynolds numbers and thus increased heat transfer coefficients. These

increased coefficients come at the expense of higher pressure drops and

thus increased pump work. An extreme example would be water which has

very high heat transfer coefficients relative to ammonia because of the

unrealistically high velocities arising from its very low vapor density.

Further reducing the practical differences between the fluids are the

small temperature differences driving evaporation or condensation. As an

example, the average condensing coefficient predicted by Equation (7) for

ammonia in the reference case condenser design is 28,000 W/m2 K; a heat

load of 10 kW and a condensing area of 0.77m2 implies a temperature

19
difference of 0.46 K. Even halving the heat transfer coefficient would

require a temperature difference of less than 1.0 K to transfer the

necessary heat. Thus, it seems reasonable to use the reference cold plate

and condenser design for all the fluids.

Pumped System

For the reference heat transport system described in the previous

section, the fluid mass flow rate, assuming complete evaporation in the

cold plate , is

Q

m = (10)

hfg

where Q is the heat load and hfg is the latent heat of vaporization. The

required strength of the piping and accumulator will depend on the

operating pressure - the vapor pressure of the fluid at the maximum

temperature of 80° C. The minimum wall thickness specified by the ASME

pressure vessel code (as summarized by Perry [6]) is used:

PD0 8 = — + C (11)

2 (SE+0 . 4 P)

where 5 is wall thickness, P is pressure, D0 is the outside pipe diameter,

E is a weld factor (taken here as 1.0 on the assumption of drawn tubing or

fully- inspected welds) and the factor 0.4 is the stress reduction factor

appropriate for non-ferrous materials. The corrosion allowance, C, is

taken as zero. The allowable stress, S, is given in [6] for a wide

variety of materials; it is 0.20 - 0.25 times the tensile strength and is

62,000 kPa (9,000 psi) for 6061-T6 aluminum and 200,000 kPa (29,000 psi)

20
for stainless steel. The wall thickness is subject to a minimum value of

0.8 mm to provide sufficient rigidity for handling, joining, etc.

The piping diameter has a large influence on system weight. Small

diameters decrease the weight of not only the piping itself but also the

required fluid charge and thus the weight of the accumulator. Offsetting

these benefits are increased pressure drop and pumping power. The optimum

diameters are determined by a Fibonacci search technique (described in

Appendix B) , applied separately to the liquid and vapor lines.

For a giyen fluid, the necessary fluid properties, fluid mass flow

rate, etc. are evaluated at 20°C . The Reynolds number and resulting

friction factor are computed for a given guess of liquid line diameter.

For laminar flow:

f = 16 Re' 1 (12)

For turbulent flow and hydraulically smooth tubes:

f = 0.046 Re' 0 2 (13)

The theoretical pump work is given by:

32 f L m

3 W = (14)

7T 2 p

2 D, 5

where L is the pipe length (30m)

p is the fluid density, and is the

inside pipe diameter. The equivalent weight due to pump work is then

calculated by applying the factor of 0.25 kg/W.

The weight of the tubing Mt is simply:

Mt = p ttt 6 D0 L (15)

21
where p t is the density of the tube material.

The incremental volume of the accumulator is proportional to the pipe

volume

va0 = 7 0.25 * Dj 2 L (16)

where 7 is the proportionality factor between the volume of the accumulator

and the remainder of the system (1.2 for the reference system). The mass

of the fluid charge is then:

* Mf = pVac (17)

Assuming a cylindrical shape and ignoring for the moment the contribution

of the ends, the weight of the accumulator itself is:

^ac Pac ^ac ^ ^ac ^ac,

where the wall thickness is given by Equation (2) to yield:

Pac P * Dac Lac Mac = — ——

2 (S + 0.4 P)

But note that tt Da J Lac is just four times the volume so that:

Ma c

2 Pac P ^ac

S + 0.4P

(18)

(19)

( 20 )

Thus the weight of the accumulator is independent of the diameter/length

ratio. The value given by Equation (20) is multiplied by 1.15 to allow

for end fittings.

22
The above calculations yield values for the equivalent weight

associated with the pump work, and piping, fluid and accumulator weights

for the liquid line. These are summed and the process is repeated for

different diameters until the minimum weight is found. (See Appendix B

for a description of the optimization routine) . The entire optimization

process is then repeated for the vapor line. The diameter is constrained

to a maximum of 38mm.

The pressure drop through the condenser (assuming complete phase

change) is given by the Friedel model [7]:

AP = 0.0437 L m

1 - 8 ^0 2 r

D

4 . 8

r Pt

i + —

r > Mg

0 • 2

-i

L

< Mi .

-

( 21 )

where /j. is viscosity and the Z and g subscripts refer to the liquid and

vapor respectively. For the annular flow passage in the condenser the

hydraulic diameter is used. Equation (12) applies to each of the parallel

channels so that the total mass flow rate would be divided by eight. The

pump work necessary to overcome this pressure gradient is given by:

AP m

Wp = (22)

P

But since the average fluid density is changing as a function of quality,

Equation (22) must be integrated over the quality range one to zero to

yield for complete condensation:

23
w

p

0.1421 m

2 - 8 L nt 0 - 2

Pi 1)4 ‘ 8 (P g

- Pi)

« -2 + In

r > p 8

r~

V.

_L i

l Pi J » Pg “ Pi >

f > ^g

0.2 ^ ' Pg

2

' Pi

2

(p6

- Pi) 2 2

2 Pi

( 23 )

Pi ) + Pi

2 In

r i

>

IPiJ j

The evaporator (cold plate) design is for parallel liquid and vapor

channels. The pump work is evaluated by summing the individual single

phase pressure drops and integrating over the length of the evaporator

with vapor quality assumed to vary directly with length:

Z-L

w

p =

(l-X) m (5P/SZ), X m («P/«Z) V

+ —

Pi Pv

dZ

z=o

(24)

where Z is distance and X is quality, so that (l-X) m represents the liquid

mass flow rate. The pressure gradient, 5P/6Z is:

8 P 32 f rh2

8 Z 7T 2 p D

5 (25)

Carrying out the integration in Equation (24) yields:

W

p = 0.03739 L m

2 • 8

' Mv

°

’ 2 0 . 2 +

. Pi ^i

A . 8 Pv

2 Dv

A . 8 (26)

where and Dv are the diameters of the liquid and vapor channels,

respectively.

The contributions of the pump work, fluid and accumulator weights in

24
the condenser and evaporator are added to those of the liquid and vapor

lines to arrive at a total fluid-dependent system weight. This serves as

the primary figure of merit for thermal performance.

Capillary System

For the capillary-pumped system, the circulating pump is replaced by

a wick that induces flow through capillary forces. The maximum pressure

differential that can be thus generated is:

2 a

AP = — (27)

r

where a is surface tension and r is the effective radius of the wick (5 p,m

for the reference case) . The maximum pressure differential given by

Equation (27) is multiplied by 0.9 to account for inefficiencies in the

capillary pumping process.

The major difference between the analysis for the pumped and capillary

systems is that, for the capillary system, the total AP is fixed by the

fluid properties and the wick and cannot be arbitrarily varied by the

input of pump work. The optimization problem will be to best allocate a

fixed AP between the liquid and vapor lines. For a given fluid the

pressure drops through the condenser and evaporator are evaluated as

above. The remaining AP is allocated between the liquid and vapor lines

and the diameters necessary to accommodate the flow rate at the specified

AP are calculated. For laminar flow:

D 2.526

_ 0 . 2 5 L fh /i

p AP

(28)

25
For turbulent flow:

_ o . 2 o 8 3

D = 0.6660

L m

1 • 8 2

p AP

(29)

The system weight is then computed. The allocation of the AP is then

varied by a Fibonocci search method to find the optimum value. The

resulting system weight is then used for ranking each fluid.

26
FLUID SELECTION AND DISCUSSION

Pumped System

The 52 fluids which passed the preliminary screening were evaluated

in terms of incremental system weight; the results are presented in Table

4. At this point one must consider the characteristics of chemical stability,

toxicity, flammability, etc. to arrive at the 'best' fluid(s) . If the

thermally- top-ranked fluid (ammonia in this case) were also nontoxic and

nonflammable there would be an unequivocable best choice, but unfortunately

this is not the case.

The toxicity and flammability of the 52 fluids are classified in terms

of the Threshold Limit Value (TLV) and lower explosive limit (LEL) and listed

along with the maximum operating pressure in order of thermal ranking

(incremental system weight) in Table 4. The Threshhold Limit Value is a

measure of chronic toxicity; it is the concentration in air to which a

worker may be exposed for 8 hours a day on a long-term basis. A higher value

of TLV thus represents a less toxic compound; a value of 1000 ppm (parts per

million) is generally the maximum value and is assigned only to compounds

of very low toxicity. For some compounds, the status of toxicity testing

is sufficient merely to classify as "toxic" rather than quantify with a

numerical TLV. The indication of "simple asphyxiant" (S.A.) in Table 4

refers to a compound of such low toxicity that the major hazard to health

would be asphyxiation through the displacement of oxygen. Flammability is

quantified in terms of lower explosive limit; LEL is the concentration in

air which will just ignite and sustain burning. A low value of LEL thus

represents a more flammable compound. Sources for toxicity data include

[8, 9, 10]; flammability data were taken from [9] as well as directly from

27
the PPDS data base.

Starting at the top of Table 4, ammonia has the highest thermal

rating (i.e. lowest system weight) and is thus automatically a candidate

for consideration. Ammonia is, however, moderately flammable and toxic and

operates at high system pressures.

28
Table 4 Ranking of Fluids for Reference System

Based on Incremental System Weight

PPDS Formula Inc . wt Pressure Flammability Toxicity Name /comments Consider

# (kg) (kPa) (LEL- v%

)

(TLV-ppm) Further

70 nh3 27.5 4141

15.0 25 ammonia X

58 c3 h6 32.5 3719. 2.0 S.A. similar to propane

57 C 3 H 8 32.9 3136. 2.1 S.A. propane X 60 c 3 h, 34.9 2244. - 1000 propyne

potentially unstable

66 c3 h. 35.2 2779. - - similar to propane

554 ch3 nh2 35.5 1655. 5.0 10 methylamine X 143 ch2 0 35.6 2318. 7.0 2 196 C2 H2 0 36.5 3983. - 0.5

111 c2 h6 o 37.6 2224. 3.4 (toxic)

485 ch2 f2 43.1 5816. - - R32 -probably X non toxic

355 ch 3 ci 45.2 2156. 10.7 50

375 cos 45.3 4000. 12.0 (toxic)

48 c4 h 10 46.1 1335. 1.8 1000 iso-butane X 423 (ch 3

) 2 nh 47.0 1016. 2.8 10

49 c 4 h8 48.0 1196. 1.7 S.A. similar to iso-butane

492 c2 h4 f2 48.1 2328. 3.7 1000 R1 52a-mod

X flammable

7 c 4 h6 48.5 1151. 1.4 1000 similar to iso-butane

9 c4 h8 49.4 1201 . 1.6 S.A. similar to iso-butane

11 c4 h 8 52.3 996. 1.7 S.A. similar to iso-butane

422 c 2 h5 n2 52.9 768. 3.5 10

8 c 4 h 10 53.0 1015. 1.9 800 n-butane

170 c,h4 53.8 855. - - similar to iso-butane

10 c 4 h8 54.0 928. 1.7 S.A. similar to

iso-butane

369 chcif2 54.8 3648. non 1000 R22-non toxic, X non flammable

216 (ch3 ) 3 n 55.5 9412.0 ( toxic

)

130 C 2 H 3 Ci 57.1 1485. 3.8 5 373 ch 4 s 58.2 937. 3.9 0.5

154 Cl 2 59.1 2737. non 1 193 c2 h4 o 59.4 872. 3.7 10

6 c,h6 60.5 802. - - 228 so2 63.8 1811. non 2 64 c2 h4 o 64.3 608. 4.0 100

12 C.Hg 69.1 842. - - 482 CF3 Br 71.0 3965. non 1000 Halon-1301 fire X fighting agent

431 CC1 2 F2 72.6 2291. non 1000 R12- lower X pres, than R22

490 c2 h 3 cif2 72.8 1441. 6.2 1000

436 c2 cif5 73.3 3150. non 1000

177 c2 h 5 ci 75.0 751

3.8 1000

313 c 5 h 10 82.4 566. 1.5 - 211 c 3 h 5 ci 87.9 551. 4.5 ( toxic

)

439 c 2 h2 cif3 97.4 947. - - 380 HI 100.0 2668. - (toxic)

434 CHC12 F 105.8 853. non 10

486 CH3 Br 107.1 971. 8.6 10

467 BC1 3 114.7 702. -

( toxic)

649 C2 H3 Br 121.2 621. 5.6 1 487 C2 C1 2 F4 130.4 940. non - 432 CBrClF2 133.1 1128. non - 435 c2 CI 2 F2 133.1 929. non 1000

440 cci 3 f 143.7 527. non 1000 Rll-include for X comparison

483 CBr2 F2 197.4 545. non 100

63 H2 0 675.1 58. non non water

Notes

S.A. indicates a simple asphyxiant

indicates no data
A fluid with a lower thermal rating would warrant consideration if it

avoided the safety-related shortcomings of ammonia. Moving down the list,

the next four fluids are hydrocarbons of low toxicity but which are highly

flammable. These different tradeoffs relative to ammonia warrant inclusion

in the final list. These four materials are all similar, three-carbon

hydrocarbons and thus only one of the four need be considered further;

propane is chosen because it is the most stable and readily available

material among the four. Methylamine has a good thermal rating, is

somewhat less flammable than propane, slightly more toxic than ammonia

and, most significantly, operates at lower pressures than ammonia or

propane. Continuing down the list, formaldehyde can be eliminated; it is

toxic, flammable, and operates at moderately high pressures, i.e. it has

no advantages over fluids with higher thermal ratings. Similarly, ketene

can be eliminated - it is not only toxic, flammable and operates at high

pressures but is also chemically unstable. Applying similar reasoning,

difluorome thane (R32) , iso-butane and 1 , 1 -dif luoroethane (R152a) are

included in the final list.

Chlorodifluorome thane (R22) is the first nonflammable fluid; R22 is

also of very low toxicity. These attributes come at the expense of high

operating pressures and an incremental system weight nearly twice that for

ammonia

Flammable and/or toxic fluids with a thermal rating lower than R22

can be dismissed out of hand. There are several additional fluids,

however, that warrant inclusion in the final list. Bromotrifluorome thane

(Halon 1301) is a fire-fighting agent. The relatively poor thermal rating

for Halon 1301 arises in large part from its very high liquid density;

30
this penalty might be offset if the heat- transport system could be

integrated with the fire-fighting system. Dichlorodifluoromethane (R12)

operates at lower pressures than R22. Chlorotrifluoromethane (Rll) is

ranked very low but since it is the currently used fluid in some systems

it is included in the final list for comparison purposes.

Consideration of thermal, toxicity and flammability characteristics have

reduced the original list of 860 candidates to a final 10: ammonia,

propane, methyamine, R32, iso-butane, R152a, R22, Halon 1301, R12 and Rll.

They are all stable at normal temperatures. With the exception of R32 all

of these materials are readily available at reasonable cost: For the most

part, these fluids are in very widespread use with very good property data

and a large store of materials compatibility data available. Ammonia and

methyamine are the most demanding with regards to materials compatibility,

but suitable materials exist even for these.

Variation in System Parameters

The selection process leading to the set of 10 preferred fluids was

necessarily carried out for a system with a fixed set of parameters - the

reference system described in a previous section. This raises the

question of whether the ranking of fluids would be changed for a different

set of system parameters. The effects of differing system parameters will

be examined by means of a factorial design.

The statistical analysis method known as a factorial design is well

suited to the investigation of a number of variables and the interactions

among variables. The most common design, the one employed here, adjusts

the variables (also called factors) between two levels in a specified

31
fashion. The results of the analysis are a main effect for each variable

and interactions between variables. A main effect is the response of a

dependent variable (e.g. incremental system weight) to a change from the

low to high level of an independent variable (e.g. design heat load)

taken over the average of all other factors. Interactions measure the

result of two or more variables simultaneously changing from their low to

high level. A thorough discussion of factorial designs may be found in [11].

The effects of changing nine key system parameters will be investigated

by a factorial design for each of the 10 preferred fluids. The parameters

of design heat load, transport (pipe) length, pump weight ratio, accumulator

to system volume ratio, evaporator and condenser volume, minimum liquid

and vapor tube wall thickness and maximum tube diameter will be varied

from 30% below to 41% above the reference values (to yield a factor of 2.0

difference between the 'low' and 'high' levels for each variable). For

the tube and accumulator material, the density and tensile strength for

6061 -T6 aluminum will be taken as the low level and the properties for

type 304 stainless steel will represent the high level. The final

variable is the safety factor (over and above that allowed for in Equation

(11)) for the pressure rating of the accumulator and piping; values of 1.0

and 2.0 are assumed for the low and high levels respectively.

The results of the factorial analysis are presented in Table 5. The

first column gives the 'average' incremental system weight for each of the

10 fluids; this figure is the system weight evaluated with all of the

variables at an average of the high and low values. These values are

somewhat higher than the system weights for the reference case since for

two of the variables (tube material and safety factor) the reference

32
system corresponds to the 'low' level rather than an average of the high

and low levels.

The main effects presented in Table 5 are expressed as a fraction of

the average incremental system weight. For example, the value of 0.251

for the effect of heat load for ammonia means that an increase in the heat

load from 7 kW (the 'low' level) to 14 kW (the 'high' level) would

increase the system weight 0.251 times the average (or 11.1 kg). One can

use these results to examine the impact of different design parameters.

(Interactions between variables were also computed but were generally much

smaller than the main effects and are not presented here) . ,

The main effects for the 10 fluids are all positive except for the

factor of maximum tube diameter. For 9 of the 10 fluids this factor has a

main effect that is very small or zero; for these fluids the optimum

liquid and vapor line diameters are usually less than the maximum value so

that varying this factor has little or no effect. For the low pressure

Rll, however, the effect is negative; larger diameter vapor lines result

in a more efficient system.

Although, for the most part, the signs of the main effects presented

in Table 5 are the same, the magnitude of the values vary considerably

among the various fluids. For example, the weight for a system using

ammonia is much less sensitive to pump efficiency than an Rll system. In

general, the magnitude of the effects depends on the fluid vapor pressure.

The high pressure fluids (e.g. ammonia and R32) and low pressure fluids (e.g.

Rll and iso-butane) tend to have effects which are of opposite magnitudes.

This, along with the observation that the high-ranked fluids tended to be

those with high vapor pressures, suggests that a system with a different

33
Table 5-

Results

of

Factorial

Design -

Variation

of

System

Parameters

a) 423

4-> Xc

5-i a) p

cdE

cd

•lH E X

5-i P O

0) -P

4-1

O

cd cd V) 4-1

cd

O • °tH g .c

•H P E o

-3 >

CXX

d)

C ^ > O J

(DO'-'

cO

•«HP

0) p

cOEO>O P O CO

cO P

cd a,

Vipopo

cO

on

VO co

cmm o o

tP CM

VO CO

lO

h o o

42 5 bO O -P I

co

0)>

<D X

OO ooo or-H o ooo oo

r»oo ooo ooo

p"-

r-H o

LOCM

co X

•rH3

CM

LOCM

LOOn

r-o

co

LOCM

in

r»» o

CM LO<r

VOCM

r^- r-o

COoo . r-H ON CM oo r- CM ON o CO O t—

Cp VO

m o ON VO

m co o oo in

0) CO CO co CM CM CM CM CM

p o X bO o • o • o o • o • • a) cO p P P a)

a) >

co in 4-1 cO • <u t—1 CM p <P 00 o CM

m vO O' CO CO <± r"» \ \ a O VO r-» on in CM o oo ON nCM r-H r-H r-H o r-H r-H r-H o o O • o S2 vO <M r-H O

r-H •rH ‘

CDp

X o p cO • P

CO P 4-1 CO on CM cn o CO

m CM in, r-H o o o ON oo O'. r-H on co CM T". VO < CO 4-1 CO CO T—

r-H CM r-H <7*H CM CM r-H

O P

cO • • 0 * • ° ° ° e •

42 X) - bO <D •rH CO

0) CO

m o £ a) oo r-. p 00 CM o 00 ON vO r-® CM

O • E a CO m r- VO r-* r-H o cn O <“H 0) X co co CM CO -d- eo CM p <d • • • • • • • • • - CO '—/

>M

CO CO p C o

r- <f o CD m 4-1 VO oo CO

m

m 00 CM CM

m

r-H CO CO 4-! ON VO r-H vO

m 00 r-H o • p <D o r-H r-H r-H CM r-H r-H r-H CM o

<D 4-1 CP

<D

C

Of—j

Cti s

42P CM c 1 <D bO • • •rH 1 CO CO <r CO I-". CM

m CM

ag s tP CM cd 1 vO VO 00 in co ON

O

•H CD CM E 1 co CO

m VO

G-i •—

1 • • • • • • • • • X 1 C 1 cd 1 P 1 P X r-* H 42 1 Cd Cd & o . bO 1 H o 00 Tp co 00 Tp ON ON <r

CD

O • •rH 1 in CM 00 Tp CM o m CM

42

—

r** Tp CD 1 CM <fr CO CO VO in O' 5 1 • • • * • • ’ • • • E

a) p

co>N bO VO vO Tp in ON Tp CO r^- V) X CM ON ON co m in CM 00 r^. • • ® > • • » • • H <D CM o oo 00 oo 00 ON 00

cd bOm

m vO vO VO ON ON co

p cd CM G P

CD CD E >

CD < poC CD <D r-H

•rH

G

C o

•rH cd co

<D cd (D E p r-H b0 •iH C cd 3

cd

X c cd >N 42 cd

C P •rH O Cl tG i CM o

(D 3 £ O

p CM

O

m CM *-H CM > r=H g P <D CO W r-H CM TP < Ph cd a E cd •rH cd cd X cd cd
set of parameter values might yield a substantially different ranking of

fluids

The parameters that would favor a low pressure fluid are low values

of heat load, pipe length and pump weight ratio, and high values of

accumulator volume ratio, condenser and evaporator volume, minimum tube

wall thickness, maximum tube diameter, and tube safety factor, with

stainless steel as the construction material. With this set of system

parameters the full set of 52 fluids passing the preliminary screening

were evaluated and ranked according to incremental system weight. The

results are presented in Table 6; for comparison purposes, this table also

summarizes the base case results. The previously highly-ranked (but also

high pressure) ammonia and propane fell to about midway down the list.

The top three fluids are methyamine, diethylamine and iso-butane, but

considering the toxicity of the amines, the substantially less toxic, but

only slightly more flammable iso-butane might be the best choice among the

three. Applying criteria of toxicity and flammability as in the previous

section, one might consider ammonia, R152a and R142b on the basis of

reduced flammability compared to iso-butane. Sulfur dioxide is nonflammable

but highly toxic. Again, R22 is the highest-ranked fluid which is both

nontoxic and nonflammable, although R12 has a nearly identical thermal

rating and would be preferred for its lower operating pressures. Perhaps

the most surprising result is that for Rll. Even though the parameters

were selected to favor Rll, it remains very near the bottom of the list,

although the relative difference between it and the top ranked fluid has

decreased. Even with a substantial change in system parameters, the list

of preferred fluids is not substantially different. The relative thermal

35
ranking of some of the fluids within the list may have changed but the

unquantifiable tradeoffs among thermal performance and safety considerations

remain.

Among the set of 52 fluids, Rll has the lowest vapor pressure (apart

from water) and was very near the cut off value for the product of latent

heat and the vapor density. To check whether other fluids might perform

well in the 'low pressure' system an expanded set of 204 fluids was

considered. This set was comprised of those fluids having a latent heat

times vapor density greater than 0.1 kJ/L (versus 1.0 kJ/L for the

original set of 52 fluids) . Twenty- seven fluids were ranked higher than

the nontoxic, nonflammable R22; these are summarized in Table 7. all of

these fluids are flammable. For the most part, they represent minor

variations on fluids seen in the previous set of 52 fluids; for example,

pentane and isopropylamine are added to the hydrocarbons and amines

already examined. The one completely new compound is tetramethylsilane

,

Si(CH4 ) A

. While this exercise does not alter the list of recommended

fluids for the system considered in this study, it does point out the need

to re-examine the choice of working fluids when system parameters or

constraints change significantly.

36
#

70

58

57

60

66

554

143

196

111

485

355

375

48

423

. 49

492

7

9

11

422

8

170

10

369

216

130

373

154

193

6

228

64

12

482

431

490

436

177

313

211

439

380

434

486

467

649

487

432

435

440

483

63

Table 6 - Comparison of Thermal Rankings for Reference System

with Those for System Favoring Low Pressure Fluids

Base Case Low Pressure Case

Formula Inc. Wt.

(kg)

PPDS

#

Formula Inc. Wt.

(kg)

Name/comments

nh3 27.5—.

j— 554 ch3 nh2 56.2 me thyamine- toxic

c 3 h6 32 . 5 —l- /

423 (CH3 ) 2 nh 57.2

c3 h8 32.9 —

/ r 48 CaH 10 57.5 iso-butane

c 3 ha 34.9 \y c,h8 58.0

c 3 h, 35.2 n

/

7 c,h6 58.5

CH, NH, 35 . 5 —'It /

8 C*H10 58.5

CH2 0 35.6

/

11 c 4 h8 58.6

c2 h2 o 36.5 1) 9 c4 h8 58.7

37.6 I 422 C,H^NH, 59.0

ch2 f2 43.1 —

/

10 c4 h8 59.2

CH3 C1 45.2 /' 1 170 c 4 ha 59.8

cos «.3 r 46.1—'

ll 60 c 3 h, 59.9

C*H10 11 216 (CH3 ) 3 N 60.2

(CH, ),NH 47.0

1 6 c4 h6 61.9

c,h8 48.0

1 111 c2 h6 o 62.2

c2 h4 f2 48.1 —

1 143 ch2 o 62.7

c a h6 48.5 \

l 57 C 3 H 8 63.9 propane

c,h8 49.4 \ 66 c 3 h, 64.1

c,h8 52.3 \ 64 c2 h2 o 65.3

c2 h5 n2 52.9 ’ 1 373 ch3 sh 66.2

CaH10 53.0 193 c2 ha o 66.5

c*h4 53.8 \ 12 c 4 h6 67.8

c,h8 54.0

\ *—70 nh3 68.0 ammonia- low flam

chcif2 54.8—,

\

58 c 3 h6 68.3

(CH3 ) 3 N 55.5 \ \ 313 C 5 H 10 69.6

c2 h3 Ci 57.1 \ \ 355 CH3 Ci 70.2

cha s 58.2 \ \ 130 C2 H 3 Ci 70.9

Cl 2 59.1 \ \177 C, H«; Ci 72.6

c2 H,0 59.4 \

j '-492 c2 h, f2 73.2 R1 52a

c,h6 60.5 \ 196 c2 h2 o 77.1

so2 63.8 \ 211 C 3 H5 CiF 79.6

c2 ha o 64.3 ' 490 C2 H3 CiF2 81.7 R142b

C4 H6 69.1 l 228 so2 85.2

CF3 Br 71.0 —

ft 375 cos 86.0

cci 2 f2 72.6-.

\ 154 Ci 2 90.9

c2 h3 cif2 72.8 \ \ 439 C2 H2 CiF3 90.9

c2 cif5 73.3 1 \ *—369 CHCiF2 92.7

c2 h5 ci 75.0 1 ^-431 CCi2 F2 92.8 R12 non- toxic,

non- flam

c5 h10 82.4 1 434 CHCi2 F 96.3

C,H,C1 87.9 — 485 ch2 f2 98.5

C2 H2 C1F3 9 7..4 1 436 C2 CiF5 100.1

HI 100.0 1 467 BCi 3 100.3

CHC1 2 F 105.8 \ 486 CH3 Br 103.9

CH3 Br 107.1 1 487 C2 Ci 2 fa 108.3

bci 3 114.7 1 649 C2 H3 Br 108.8

c2 H3 Br 121.2 1 435 109.3

C2 Ci 2 FA 130.4 '—482 CBrF3 110.9 Halon 1301

CBrClF2 133.1 432 CBrCiF2 118.0

C2 C1 2 Fa 133.1 ^—440 CCi 3 F 120.4 Rll

cci 3 f 143.7 ^ 380 HI 131.8

CBr2 F2 197.4 63 h2 o 164.4

H2 0 675.1 483 CBr2 F 166.2

Cons ider

Further

x

x

X

X

X

X

37
Table 7 - Summary of Fluids in Expanded Set With a Higher

Thermal Rating Than R22 in 'Low Pressure' System

PPDS Formula Inc. Wt. Pressure Flammability Toxicity Name

# (kg) (kPa) (LEL - v%) (TLV-ppm)

Selected fluids from set of 52:

48 C*H10 57.5 1335 1.8 1000 iso-butane

57 c3 h8 63.9 3136 2.1 S „ A. propane

70 nh3 68.0 4141 15.0 25 ammonia

492 c2 h, f2 73.2 2328 3.7 1000 R152a

490 C*2 ^3 C^F2 81.7 1441 6.2 1000 R142b

369 CHCiF2 92.7 3648 non 1000 R22

431 CCi2 ^2 92.8 2291 non 1000 R12

Additional fluids considere d:

556 c3 h9 n 70.3 461 2.0 - . isopropylamine

42 ^5 H 1 2 71.8 457 1.4 - isopentane

311 c5 h10 73.1 437 1.4 - 109 c5 h8 73.8 380 1.0 (toxic)

312 c5 h10 75.0 427 1.7 - 578 Si (CH3 ) 4 75.9 455 1.6 - tetramethylsilane

56 c 5 h12 76.3 368 1.4 1000 pentane

121 ^ 5^1 0 77.2 369 1.4 - 120 c5 h10 77.8 363 1.4 - 97 C,H10 O 77.9 402 1.9 400 diethylether

167 c3 h6 o 78.0 423 2.8 100

110 c 5 h10 79.7 347 1.4 - 517 c,h8 o 80.7 391 1.7 - 374 c2 h6 s 80.7 393 2.8 0.5

555 c3 h9 n 81.6 290 2.0 (toxic) n-propy famine

197 ^2^4 ®2 82.3 467 5.0 100

514 ca h10 o 83.1 352 2.0 - 118 c 5 h8 83.3 305 1.5 - 570 c2 h6 s 83.4 367 2.2 - 117 c 5 h8 85.1 288 1.5 - 17 c 5 h6 85.4 335 - - 194 c 4 h,0 85.5 450 2.3 (v. toxic)

827 ^6 ^1 2 86.6 310 - - 19 c 5 h8 86.7 292 1.8 (mod. toxic)

384 c 3 h7 cs. 88.2 387 2.8 - 123 c 3 h6 o 88.8 276 2.3 (mod. toxic)

445 ^3 ^8 ^2 90.7 331 3.1 1000

38
Capillary System

A capillary-pumped system is also considered. The design of this system

is basically the same as the reference system except that the lower design

heat load of 2 kW (versus 10 kW) implies only one cold plate (versus four)

and a smaller condenser. The transport length between the cold plate and

condenser remains 30 m. The results for the set of 52 fluids is presented

in Table 8.

As with the pumped system, ammonia receives the highest thermal

rating (i.e. lowest system weight) for the capillary system. But again a

fluid avoiding the hazards of ammonia would be desirable.

The choices for the capillary system are more limited - for 12 of the

52 fluids the pressure drop in the condenser and evaporator exceeded that

which could be generated by capillary forces. (The allocation of AP

between the liquid and vapor lines was optimized with 68% to 80% in the

vapor line .

)

Moving down from the top of the list, methylamine would warrant

consideration for its lower operating pressures. Of the next 14 compounds,

9 are both more flammable than ammonia and highly toxic. The remaining

five are hydrocarbons which are of low toxicity but, of course, highly

flammable. Propane, although ranked lower than the unsaturated C 3 HA , C3 H6 and C a H6 would be favored for its greater stability. Iso-butane is ranked

lower than propane but would operate at substantially lower pressures.

The fluorinated compounds R32 and R152a combine low toxicity with moderate

flammability. Three nonflammable compounds appear feasible in the

capillary system; the first two - sulfur dioxide and chlorine - are highly

toxic. Only R22 is nonflammable and of low toxicity. R12 might be

39
considered for its lower operating pressure than R22. It, however, is on

the verge of not operating - 88% of the 3.3 kPa pressure rise generated by

capillary forces was consumed in the condenser and evaporator, leaving

only 0.4 kPa to transport the liquid and vapor between the condenser and

cold plate.

40
PPDS

#

70

554

143

60

196

422

423

66

193

373

111

170

64

7

355

57

58

10

49

9

11

6

216

48

8

228

130

177

12

492

154

375

485

369

486

211

490

434

380

431

Table 8 Ranking of Fluids for Capillary System

Formula Inc . wt

(kg)

Pressure

(kPa)

Flammability

(LEL - v%)

Toxicity

(TLV-ppm)

Name

nh3 8.76 4141 15.0 25 ammonia

ch5 n 10.23 1655 5.0 10 methylamine

ch2 o 11.27 2318 7.0 2 c 3 ha 12.68 2244 1000 propyneuns table

c2 h2 o 12.77 3983 - 0.5

c2 h7 n 12.80 768 3.5 10

c2 h7 n 12.89 1016 2.8 10

C3 Ha 13.28 2779 - 0.5

c2 h4 o 13.70 872 3.7 10

ch4 s 13.72 937 3.9 0.5

c2 h6 o 13.82 2224 3.4 (toxic)

c*h4 14.42 855 - - c2 h4 o 14.75 608 4.0 100

CaH6 14.78 1151 1.4 1000

ch3 cs. 15.00 2156 10.7 50

c3 h8 15.32 3136 2.1 S . Apropane

c3 h6 15.40 3719 2.0 S . A.

c,h8 15.75 928 1.7 S . A.

c 4 h8 15.99 1196 1.7 S .A.

CaH6 16.08 1201 1.6 S . A

c*h8 16.13 996 1.7 S . A.

16.60 802 - - C 3 HqN 16.99 941 2.0 ( toxic)

C*H10 17.42 1335 1.8 1000 iso-butane

C,H10 17.44 1015 1.9 800

so2 18.13 1811 non 2 c 2 h3 CJl 18.47 1485 3.8 5

C 2 H5 Ci 19.27 751 3.8 1000

c.h6 19.59 842 - - c2 h4 f2 20.25 2328 3.7 1000 R152a

Ci 2 21.00 2737 non 1 cos 21.59 4000 12.0 (toxic)

ch2 f2 22.17 5816 - - R32

CHC2F2 27.87 3648 non 1000 R22

ch3 h5 cz 30.45 971 8.6 10

C3 H4 Ci 32.98 551 4.5 ( toxic)

c 2 H3 C 2 F2 34.41 1441 6.2 1000

CHCi2 F 37.76 853 non 10

HI 40.11 2668 -

( toxic)

CCi 2 f2 52.25 2291 non 1000 R12

41
The eight preferred fluids for the capillary system are all among the

ten selected for the pumped system; the relative ranking among the eight is

also nearly the same between the two systems. This is a most interesting

result considering the differences between the systems. Although eight

fluids are presented for the capillary system, in practice only the top

two or three may really be feasible. R22 has an incremental system weight

over 3 times that of ammonia (27.9 vs. 8.8kg) for the capillary system

while for the pumped system the ratio is only 2:1 (54.8 vs. 27.5kg). The

mechanical simplicity of the capillary system does not come without penalty.

42
OBSERVATIONS ON THE IDEAL FLUID

Upon examining the fluids which passed the various screening and

ranking criteria set forth in this work, a number of general conclusions

can be drawn relative to the characteristics of the ideal fluid for twophase heat transport systems. The first, and most significant, is that

all of the preferred fluids are simple, low molecular weight compounds.

The most complex is iso-butane with 14 atoms; Halon 1301 with a molecular

weight of 149 is the heaviest. Even considering the larger list of 52

fluids which passed the preliminary screening the largest molecule has

only 17 atoms and the maximum molecular weight is 171 (for R114)

The major quality associated with a low molecular weight is a high

latent heat of vaporization (on a per mass basis) . This is reflected in

Troutons Rule which is the empirical observation that for nearly all

fluids the molar heat of vaporization is proportional to the boiling point

temperature. Since only a relatively narrow range of boiling points will

permit operation in the two-phase region, it follows that low molecular

weights will yield high latent heats on a mass basis. A higher latent

heat in turn requires a lower mass flow rate to remove a given quantity of

heat. Pump work is further minimized by the general trend of simpler

molecules having lower viscosities.

The second major observation is that the higher ranked fluids were

those with higher vapor pressures. This applied not only to the group of

fluids as a whole but also within classes of fluids; as examples, among

the amines ammonia was ranked higher than methyamine and for the hydrocarbons,

propane was ranked higher than iso-butane. High vapor pressures imply

high vapor densities. This minimizes the pump work associated with moving

43
the vapor and permits the use of smaller diameter piping, which has

further benefits in reducing the required fluid charge. Only with a

substantial change to the parameters of the base case system did the high

pressure fluids fall in the rankings; but even then, the very low pressure

fluids such as Rll remained near the bottom.

These considerations limit the possibilities for the ideal fluid- -only

a few elements form stable, volatile compounds. In particular, nearly all

of the 52 fluids passing the preliminary screening were composed entirely

of eight elements: carbon, hydrogen, nitrogen, oxygen, sulfur and the

halogens fluorine, chlorine, and bromine. (The only exceptions were the

highly reactive and toxic boron trichloride and hydrogen iodide) . It is

no coincidence that these same elements constitute the vast bulk of the

non-metallic materials in industrial use today.

The chemistry among the simple compounds of these eight elements is

generally well known. While the data base employed here is not exhaustive

it certainly has many representatives of all of the major classes of

compounds- -hydrocarbons , amines, ethers, alcohols, halocarbons , etc. It

is possible that similar promising compounds exist, but it seems unlikely

that a completely new class of compounds would be discovered for this

application. (As an example, 1 , 1 , 1 , 2- tetraf luoroethane , R134a, has been

receiving intense scrutiny as a refrigerant to replace the environmentally

harmful R12. Although a new fluid not yet in commercial production, R134a

is chemically and thermally similar to the compound it might eventually

replace) . Only if the rules of the evaluation were to change drastically

would substantially different conclusions be reached. For example, if

safety concerns (including toxicity, flammability and operation at very

44
low pressures) were to take total precedence over thermal performance a

different set of preferred fluids might emerge.

Only pure fluids were considered in this study; mixtures of fluids

may offer some advantages. Fluid mixtures which form azeotropes would

behave essentially like a pure fluid. Although the thermal performance of

an azeotrope is not likely to be superior to a pure fluid, there are

opportunities to manipulate other properties. For example, a mixture of a

highly-ranked but flammable fluid such as propane with a nonflammable

fluid with a lower thermal ranking might yield an azeotropic mixture with

reduced flammability and a moderately good thermal rating. The more

general class of nonazeotropic mixtures offer additional possibilities to

manipulate propeties. In constrast to pure fluids a nonazeotropic mixture

does not boil or condense at a constant temperture but rather over a range

of tempertures . While this effect may be a liability if a highly uniform

temperature is desired across the entire cold plate, it has also been

utilized to better control a two-phase heat transport system [12].

45
CONCLUSIONS

The effect of different working fluids on the thermal performance

(measured in terms of system weight) of a two-phase heat transport system

has been considered. This study has examined the externally-mounted

payload thermal control system where thermal performance is paramount.

Applying a sequence of screening and ranking criteria to a data base of

860 fluids has resulted in the selection of 10 recommended fluids. Among

these 10 fluids, tradeoffs exist among thermal performance and safety

consideration such as flammability and toxicity as summarized in Table 9.

This study has identified the best fluids within the various categories

of safety-related properties (e.g. nontoxic but flammable versus nontoxic

and nonflammable, etc.). The selection between a fluid such as ammonia with

excellent thermal characteristics but safety-related shortcomings versus a

less hazardous but also thermally- inferior fluid such as R12 represents a

question of design philosophy that can only be made by NASA.

An examination of the molecular characteristics of the highly- ranked

fluids reveals that all are simple molecules of low molecular weight with

moderate to high vapor pressures at the operating temperature. The data

base used here covers very well the few classes of chemically-stable

compounds that possess these qualities. Thus while minor variations on the

compounds identified here may prove to be better, it is unlikely that a

completely different class of compounds with better characteristics would

exist

46
Table 9 - Summary of Tradeoffs Among the Preferred Heat Transport Fluids

Formula Name Incremental Weight (kg) Pressure Flammability Toxicity

pumped capillary @ 80°C

(10 kW) (2 kW) (kPa)

nh3 ammonia 27.5 8.8 4141. moderate high

c 3 h8 propane 32.9 15.3 3136. high low

ch3 nh2 me thyamine 35.5 10.2 1655. mod. high high

ch2 f2 R32 43.1 22.2 5816. moderate low?

c a h10 iso-butane 46.1 17.4 1335. high low

^2 ^2 R152a 48.1 20.3 2328. moderate low

chcif2 R22 54.8 27.9 3648. non low

CBrF2 Halon 1301 71.0 xxx 3965. non low

CC12 F2 R12 72.6 52.3 2291. non low

CC13 F Rll 143.7 xxx 527. non low

Notes : xxx indicates :not feasible for capillary system.

47
REFERENCES

1. ASHRAE Handbook of Fundamentals, Chapter 16; American Society of Heating

Refrigerating and Air-conditioning Engineers, Atlanta, GA (1985).

2. J.L. Threlkeld, Thermal Environmental Engineering, 2nd ed.

,

Prentice-Hall, Inc. Englewood Cliffs, NJ (1970).

3. F.A. Costello, "Lotus Thermal Control System Tradeoff Program"

unpublished report to NASA (1986).

4. J.C. Chen, 'Correlation for Boiling Heat Transfer to Saturated Fluids

in Convective Flow, ' Ind. Eng. Chem. - Process Design Development

5 no 3 (1966)

5. M.M. Shah, 'General Correlation for Heat Transfer During Film Condensation

Inside Pipes,' Int. J. Heat Mass Transfer 22 547-46 (1979).

6. R.H. Perry and C.H. Chilton (ed.), Chemical Engineers Handbook, 5th ed

McGraw-Hill Book Company, New York, NY (1973).

7. G. Hetsroni (ed.), Handbook of Multiphase Systems, Hemisphere Publishing

Corporation, Washington, DC (1982).

8. American Conference of Governmental and Industrial Hygienists,

'TLVs: Threshold Limit Values and Biological Exposure Indices for

1986-87,' Cincinnati, OH (1986).

9. N.I. Sax, Dangerous Properties of Industrial Materials, 6th ed.

Van Nostrand Reinhold, New York, NY (1984).

10. American Society of Heating, Refrigerating and Air Conditioning

Engineers, Inc., 'Number Designation and Safety Classification of

Refrigerants,' proposed American national standard, public review

draft (1988)

11. C. Daniel, Applications of Statistics to Industrial Experimentation,

Wiley, New York, NY (1976).

12. F.A. Costello, personal communication (1987).

48
APPENDIX A - PPDS DATA BASE

The PPDS data base is a proprietary data base produced by the

Physical Property Data Service of the Institution of Chemical Engineers in

association with the National Engineering Laboratory (both in the United

Kingdom). It is a comprehensive collection of data on 860 pure fluids; it

can also calculate mixtures of up to 20 components. The data base

contains two types of information: constant (temperature- independent)

properties such as critical pressure and dipole moment and temperaturedependent properties such as viscosity and vapor pressure. These properties

are listed in Table A-l. Each fluid is referenced by a code number.

Table A-2 contains a listing of the available fluids.

NBS has acquired the PPDS data base in the form of an 'Electronic

Data Module.' This device is based on a Motorola MC68000 microprocessor

and stores the fluid data in 2 MBytes of EPROM memory. It communicates

with a host microcomputer over an interface (in this case a HewlettPackard series 9000 model 217 communicating over an IEEE-488 parallel

interface)

The FORTRAN application program on the host computer accesses the

data module by calling an interface subroutine with the desired fluid,

property, etc. input to the subroutine in terms of code numbers. The

interface routine then interprets this input and transmits a coded

character string over the IEEE interface to the data module. The data module

receives this transmission, interprets it, and returns the requested data

to the host computer as another character string. The interface subroutine

receives this return string, interprets it, and finally supplies the

requested data to the application (main) program. The first part of the

49
interface routine, containing a description of inputs and outputs is given

in Table A-3; the remaining details of the interface routine are machinedependent and not relevant to this report.
Table A-l Fluid Properties Available on the PPDS Data Base

Constant (temperature - independent) properties.

Code Number Description and units

12

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

Molecular weight

Critical temperature (K)

Critical pressure (Pa)

Critical volume (A/mol)

Melting point (K)

Boiling point (K)

Parachor (dyne 8 cm)

Vapor heat or formation (kJ/mol)

Liquid heat of formation (kJ/mol)

Flash point (K)

Lower flammability limit (vol %)

Upper flammability limit (vol %)

Autoignition temperature (K) - Solubility parameter (cal/cm3

) Acentric factor

Vapor entropy at 298.15 K (J/mol K)

Acentric factor of the homomorph

Dipole moment (Debye)

Compound name and formula

Temperature - dependent properties

Code Number Description and units

12

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

Vapor heat capacity (kJ/kg K)

Vapor viscosity (cps)

Vapor thermal conductivity (W/m K)

Vapor enthalpy (kJ/mol)

Liquid heat capacity (kJ/kg K)

Liquid thermal conductivity (W/mol K)

Liquid density (kg/m3

) Liquid coefficient of cubical expansion (K" 1

) Liquid enthalpy (kJ/mol)

Enthalpy of vaporization (kJ/mol)

Surface tension (N/m)

Saturated vapor pressure (Pa)

Liquid viscosity (cps)

Vapor density (kg/m3

) Total heat of formation (kJ/mol)

Vapor entropy (J/mol K)

Liquid entropy (J/mol K)

Entropy of vaporization (J/mol K)

Vapor Gibbs free energy (kJ/mol)

Liquid Gibbs free energy (kJ/mol)

51
Table A-2 Fluids Contained in the PPDS Data Base

(organized by PPDS code number for each of six fluids classes)

HYDROCARBONS

2 C2H2 ACETYLENE

5 C6H6 BENZENE

6 C4H6 1 ,2-BUTADIENE

7 C4H6 BUTA-1 ,3-DIENE

8 C4H10 BUTANE

9 C4H8 BUT-1-ENE

10 C4H8 2—BUTENE(CIS)

1 1 C4H8 2-BUTENE ( TRANS)

12 C4H6 1-BUTYNE

14 C6H8 1 ,3—CYCLOHEXADI ENE

15 C6H12 CYCLOHEXANE

16 C6H10 CYCLOHEXENE

17 C5H6 1 , 3—CYCLOPENTADI ENE

18 C5H10 CYCLOPENTANE

19 C5H8 CYCLOPENTENE

20 C10H22 DECANE

24 C8H16 1 , 1—DIMETHYLCYCLOHEXANE

25 C7H14 1 , 1 -D IMETHYLCYCLOPENTANE

26 C8H18 2 , 4—DIMETHYLHEXANE

28 C12H26 DODECANE

30 C2H6 ETHANE

31 C8H12 1 , 5-ETHYLCYCLOHEXADI ENE

32 C8H16 ETHYLCYCLOHEXANE

33 C7H14 ETHYLCYLOPENTANE

34 C2H4 ETHYLENE

35 C7H16 HEPTANE

36 C7H14 HEPT-1-ENE

37 C6H14 HEXANE

41 CH4 METHANE

42 C5H12 ISOPENTANE

43 C6H12 METHYLCYCLOPENTANE

44 C7H14 4-METHYL-1 -HEXENE

45 C10H22 3—METHYLNONANE

46 C6H14 ISOHEXANE

47 C6H14 3—METHYLPENTANE

48 C4H10 ISOBUTANE

49 C4H8 2-METHYLPROPENE

52 C9H20 NONANE

53 C8H18 OCTANE

56 C5H12 PENTANE

57 C3H8 PROPANE

58 C3H6 PROPENE

60 C3H4 PROPYNE

61 C7H8 TOLUENE

62 Cl 1H24 UNDECANE

66 C3H4 ALLEN

68 C9H10 ALPHA-METHYLSTYRENE

80 C9H12 I SOPROPYLBENZENE( CUMENE)

89 C12H24 DODEC-1-ENE

94 C8H10 ETHYLBENZENE

98 C8H16 2-ETHYL-1-HEXENE

101 C6H10 2 , 4-HEXADI ENE

103 C6H12 HEX-1—ENE

109 C5H8 2-METHYLBUTA-1 ,3—DIENE (ISOPRENE

1 10 C5H10 2-METHYL-2-BUTENE

114 C6H12 4—METHYLPENT— 1—ENE

115 C6H12 C IS-4—METHYLPENT-2-ENE

116 C6H12 TRANS-4-METHYLPENT-2-ENE

117 C5H8 1 . 3-PENTAD I ENE(CIS)

118 C5H8 1 ,3-PENTAD I ENE (TRANS)

120 C5H10 2—PENTENE(CIS)

121 C5H10 2—PENTENE ( TRANS

)

126 C8H8 STYRENE

131 C8H10 M-XYLENE

132 C8H10 O-XYLENE

52
133 C8H10 P-XYLENE

148 C7H12 2-METHYL-2 . 4—HEXAD I ENE

170 C4H4 VINYL ACETYLENE

223 C8H18 2,2, 4-TR IMETHYLPENTANE

224 C8H18 2-METHYLHEPTANE

241 C5H12 2 , 2—D I METHYLPROPANE

242 C6H14 2 , 2-DIMETHYLBUTANE

243 C6H14 2 , 3-DIMETHYLBUTANE

244 C7H16 2,2, 3-TRIMETHYLBUTANE

245 C8H18 3-METHYLHEPTANE

246 C8H18 4—METHYLHEPTANE

247 C8H18 3— ETHYLHEXANE

248 C8H18 2.2—DIMETHYLHEXANE

249 C8H18 2 , 3—DIMETHYLHEXANE

250 C8H18 2 , 5—D IMETHYLHEXANE

251 C8H18 3 , 3—DIMETHYLHEXANE

252 C8H18 3, 4-D IMETHYLHEXANE

253 C8H18 2-METHYL-3—ETHYLPENTANE

254 C8H18 3—METHYL-3—ETHYLPENTANE

255 C8H1 8 2,2, 3-TR IMETHYLPENTANE

256 C8H18 2,3, 3-TR IMETHYLPENTANE

257 C8H18 2,3, 4-TR IMETHYLPENTANE

258 C7H16 2—METHYLHEXANE

259 C7H16 3-METHYLHEXANE

260 C7H16 3-ETHYLPENTANE

261 C7H16 2, 2-D IMETHYLPENTANE

262 C7H16 2, 3-D IMETHYLPENTANE

263 C7H16 2, 4-D IMETHYLPENTANE

264 C7H16 3, 3-D IMETHYLPENTANE

265 C9H20 2-METHYLOCTANE

266 C9H20 3—METHYLOCTANE

267 C9H20 2 , 2-D IMETHYLHEPTANE

268 C9H20 2 , 6—DIMETHYLHEPTANE

269 C9H20 2,2, 4-TR I METHYLHEXANE

270 C9H20 2,2, 5-TR IMETHYLHEXANE

271 C9H20 4-METHYLOCTANE

272 C9H20 3-ETHYLHEPTANE

273 C9H20 2,3, 3-TR IMETHYLHEXANE

274 C9H20 2,3, 5-TR IMETHYLHEXANE

275 C9H20 2,4, 4-TR IMETHYLHEXANE

276 C9H20 3.3, 4-TR IMETHYLHEXANE

277 C9H20 3. 3-D I ETHYLPENTANE

278 C9H20 2,2—DIMETHYL-3-ETHYLPENTANE

279 C9H20 2,2,3, 3-TETRAMETHYLPENTANE

280 C9H20 2,2,3, 4—TETRAMETHYLPENTANE

281 C9H20 2,2,4, 4-TETRAMETHYLPENTANE

282 C9H20 2,3,3, 4-TETRAMETHYLPENTANE

283 C9H12 PROPYLBENZENE

284 C7H14 1 , CIS-2-DIMETHYLCYCLOPENTANE

285 C7H14 1 , TRANS-2-DIMETHYLCYCLOPENTANE

286 C7H14 1 , C I S-3-D I METHY LCYC LOP ENTANE

287 C7H14 1 , TRANS-3-DIMETHYLCYCLOPENTANE

288 C7H14 METHYLCYCLOHEXANE

289 C8H16 CIS-1 , 2-DIMETHYLCYCLOHEXANE

290 C8H16 TRANS- 1 . 2-DIMETHYLCYCLOHEXANE

291 C8H16 1 .CIS-3-DI METHYLCYCLOHEXANE

292 C8H16 1 , TRANS-3-DIMETHYLCYCLOHEXANE

293 C8H16 1 .CIS-4-DI METHYLCYCLOHEXANE

294 C8H16 1 , TRANS-4-D I METHYLCYCLOHEXANE

295 C9H12 1—METHY L-2-ETHYLBENZ ENE

296 C9H12 1—METHY L-3-ETHYLBENZ ENE

297 C9H12 1-METHYL-4-ETHYLBENZENE

298 C9H12 1 , 2 , 3-TR I METHY LBENZENE

299 C9H12 1 , 2 , 4-TRIMETHYLBENZENE(PSEUD0CUM

300 C9H12 1,3, 5-TR I METHY LBENZENE (MES I TYLEN

301 C10H14 BUTYLBENZENE

302 Cl 1 HI 6 PENTYLBENZENE

303 C13H28 TR I DECANE

304 C14H30 TETRADECANE

53
305 C15H32 N-PENTADECANE

306 Cl 6H34 HEXADECANE

307 C17H36 HEPTADECANE

308 C18H38 OCTADECANE

309 C19H40 N-NONADECANE

310 C20H42 N— EICOSANE

31 1 C5H10 PENT-1-ENE

312 C5H10 2—METHYLBUT-1—ENE

313 C5H10 3—METHYLBUT-1—ENE

314 C8H18 2,2,3, 3—TETRAMETHYLBUTANE

315 C9H20 2 , 4—DIMETHYL-3—ETKYLPENTANE

316 C8H16 PROPY LCYC LOPENTANE

317 C8H16 I SOPROPYLCYCLOPENTANE

318 C8H16 1 -METHY L- 1 -ETHY LCYC LOP ENTANE

319 C8H16 1 -METHY L-C I S-2-ETHYLCYC LOPENTAN

320 C8H16 1 -METHY L-TR-2-ETHY LCYC LOP ENTAN E 321 C8H16 1 -METHY L-C I S-3-ETHYLCYC LOPENTAN

322 C8H16 1—METHY L-TR-3—ETHY LCYC LOP ENTANE

323 C8H1 6 1 , C-2 , C-3-TR IMETHYLCYCLOPENTANE

324 C8H16 1 ,C-a. T-3-TR IMETHYLCYCLOPENTANE

325 C8H16 1 ,1 ,2-TR IMETHYLCYCLOPENTANE

326 C8H16 1 ,1 ,3-TR IMETHYLCYCLOPENTANE

327 C8H16 1 , T-2 .C-3-TR I METHY LCYC LOP ENTANE

328 C8H16 1 , C-2 , C-4—TRIMETHYLCYCLOPENTANE

329 C8H16 1 , C-2 , T-4—TRIMETHYLCYCLOPENTANE

330 C8H16 1 , T-2 , C-4-TRIMETHYLCYCL0PENTANE

331 C7H14 CYCLOHEPTANE

332 C8H16 CYCLOOCTANE

333 C9H18 CYCLONONANE

334 C10H14 ISOBUTYLBENZENE

335 C10H14 SECBUTYLBENZENE

336 C10H14 TERTBUTYLBENZENE

337 C10H14 1 -METHY L—2— I SOPROPY LB ENZ ENE

338 C10H14 1 -METHY L—3— I SOPROPY LB ENZ ENE

339 C10H14 1 -METHYL-4-1 SOPROPYLBENZENE

340 C10H14 1,2,4, 5—T ETRAMETHY LBENZ ENE

341 C10H8 NAPHTHALENE

342 Cl 1H10 1 -METHY LNAPHTHALENE

343 Cl 1H10 2—METHY LNAPHTHA L EN E 344 C12H12 1 -ETHY LNAPHTHALENE

345 C12H12 2-ETHY LNAPHTHALENE

346 C13H14 1 —PROPY LNAPHTHALENE

347 C13H14 2—PROPY LNAPHTHALENE

348 C14H16 1 -BUTYLNAPHTHALENE

349 C14H16 2-BUTY LNAPHTHALENE

350 C16H20 1-HEXY LNAPHTHALENE

351 C16H20 2-HEXY LNAPHTHALENE

352 C19H24 1 —NONY LNAPHTHALENE

353 C19H26 2-NONY LNAPHTHALENE

354 C9H18 BUTYLCYCLOP ENTANE

357 C8H12 V I NY LCYC LOH EX ENE

367 C12H26 2 , 2 . 4 , 6 . 6-PENTAMETHYLHEPTANE

376 C10H14 1 ,4-D I ETHYLBENZENE

475 C9H18 1 , TRANS-3 , 5-TR I METHY LCYC LOHEXANE

476 C8H16 OCT-1-ENE

477 C6H10 HEXA-1 ,5-DIENE

478 C18H14 O-TERPHENYL

479 C18H14 M-TERPHENYL

480 C18H14 P-TERPHENYL

481 C13H12 DIPHENYLMETHANE

591 C6H12 2 , 3-D I METHYLBUT-2-ENE

628 C21H44 N—HENEICOSANE

629 C22H46 N-DOCOSANE

630 C23H48 N-TRICOSANE

631 C24H50 N-TETRACOSANE

632 C6H12 2-METHYLP ENT-1 -ENE

633 C6H12 3-METHYLPENT-1-ENE

634 C6H12 2-ETHY LBUT-1 -ENE

635 C7H14 HEPT-2-ENE

54
636 C8H1 6 OCT-2-ENE

637 C9H18 NON-1-ENE

638 C10H20 DEC-1-ENE

639 Cl 1H22 UNDEC-1-ENE

640 C13H26 TR IDEC-1-ENE

641 C14H28 TETRADEC-1 -ENE

642 C10H14 1 -METHYL-2-PROPYLBENZENE

643 C10H1

1 -METHYL-3-PROPYLBENZENE

644 C10H14 1 -METHYL-4-PR0PYLBENZENE

702 C15H16 4-IS0PR0PYLD I PHENYL

704 C10H20 CYCLODECANE

705 C7H12 CYCLOHEPTENE

706 C8H14 CYCLOOCTENE

707 C8H16 METHYLCYCLOHEPTANE

792 C10H18 CIS-DECALIN

793 C10H18 TRANS-DECALIN

794 C12H10 BIPHENYL

795 C14H10 PHENANTHRENE

796 C14H10 ANTHRACENE

797 C9H10 INDANE

814 C10H12 1,2,3, 4-TETRAHYDRONAPHTHALENE

815 C16H10 PYRENE

825 C6H12 TRANSHEX-2-ENE

826 C6H12 2 , 3-DIMETHYLBUT-1-ENE

827 C6H12 3 , 3—DIMETHYLBUT-1-ENE

828 C10H14 1 , 3-D I ETHYLBENZENE

830 C12H10 ACENAPHTHENE

859 C10H16 ALPHA-PIN ENE

860 C10H16 BETA-PINENE

HALOCARBONS

22 C3H6CL2 1 , 2—DICHLOROPROPANE

78 CCL4 CARBON TETRACHLORIDE(IO)

83 C2H4CL2 1 , 2—DICHLOROETHANE

128 C2HCL3 TRICHLOROETHYLENE

130 C2H3CL VINYL CHLORIDE

153 CHCL3 CHLOROFORM (20)

177 C2H5CL CHLOROETHANE( 1 60)

178 C2CL4 PERCHLOROETHYLENE

182 C2H2CL2 VINYLIDENE CHLORIDE

183 C2H2CL2 1 ,2-DICHLOROETHYLENE(CIS)

184 C2H2CL2 1 , 2-DICHLOROETHYLENE(TRANS)

185 C4H5CL 1-CHLORO— 1 . 3-BUTADIENE

186 C4H5CL 2—CHLORO— 1 ,3-BUTADIENE

187 C4H6CL2 1 ,4—DICHLOROBUTENE-2(TRANS)

21 1 C3H5CL 2—CHLOROPROPENE

212 C4H6CL2 3 , 4—D ICHLOROBUTENE—

220 C2H4CL2 1 , 1-DICHLOROETHANE( 1 50A)

231 C4H8CL2 2 , 3—D ICHLOROBUTANE

232 C4H8CL2 1 ,2-D ICHLOROBUTANE

233 C4H7CL 3-CHLOROBUTENE-1

234 C4H7CL 1 -CH LOROBUT ENE-2 ( C I S

)

235 C5H1 1 CL 2-CHLORO-2-METHYLBUTANE

236 C5H10CL2 2 , 3-D ICHLOROPENTANE

237 C5H10CL2 2 , 3-DICHLORO-2-METHYLBUTANE

238 C5H9CL3 1 , 2 , 3-TRICHLORO-2-METHYLBUTANE

239 C5H9CL 3—CH LORO-2-METHY LBUT EN E

240 C5H9CL 2-CHLORO—3-METHY LBUT EN E-2

355 CH3CL CH LOROMETHANE ( 40

)

366 CH2CL2 DICHLOROMETHANE(30)

368 C2H3CL3 1,1, 1-TRICHLOROETHANE( 1 40A)

369 CHCLF2 CHLORODI FLUOROMETHANE(22)

370 C4H4CL2 2 , 3—D I CH LOROBUTAD I ENE-1 .3

371 C4H6CL2 1 , 3-DICHLOROBUTENE-2(TRANS)

372 C4H5CL3 2,3, 4-TR I CHLOROBUTENE-1

377 C4H9CL 2-CH LOROBUTANE

379 CH3IODOMETHANE

382 C3H5CL ALLYL CHLORIDE

383 C3H7CL 1 -CHLOROPROPANE

55
384

385

387

388

389

390

391

392

393

406

412

431

432

433

434

435

436

437

438

439

440

441

442

443

482

483

484

485

486

487

488

489

490

491

492

493

494

495

496

497

498

499

500

501

502

503

504

505

506

507

508

509

510

592

593

594

595

596

597

598

599

600

601

602

603

604

605

606

607

C3H7CL 2—CHLOROPROPANE

C3H5CL3 1-2-3 TRICHLOROPROPANE

C2H3CL3 1 ,1 , 2-TR I CH LORO ETHANE

C2H2CL4 1-1-1 —2—T ETRACH LOROETHANE

C2H2CL4 1,1,2, 2-T ETRACH LOROETHANE

C2HCL5 PENTACHLOROETHANE( 1 20)

C2CL6 HEXACHLOROETHANE

C4CL6 HEXACHLOROBUTAD I ENE

C6CL6 HEXACHLOROBENZENE

C3H4CL2 1 -3-D I CHLOROPROPENE

C2HBRCLF3 BR0M0CHL0R02 , 2 , 2-TR I FLUOROETHANE

CCL2F2 DICHLORODIFLUOROMETHANE( 12)

CBRCLF2 BROMOCHLORODI FLUOROMETHANE( 1 2B1

)

CCLF3 CHLOROTRI FLUOROMETHANE( 13)

CHCL2F D I CH LOROF LUOROMETHAN E ( 2 1

)

C2CL2F4 1 , 2-D ICHLORO-1 , 1 , 2 , 2-TETRAFLUORO

C2CLF5 CHLOROPENTAFLUOROETHANE(1 15)

C2F6 HEXAFLUOROETHANE

C2HCL2F3 1 1-DICHLORO-222-TR I FLUOROETHANE

C2H2CLF3 1 —CHLORO-2 , 2 , 2-TR I FLUOROETHANE

CCL3F TR I CHLOROFLUOROMETHANE( 1

1

)

CHF3 FLUOROFORM( 23)

C2CL4F2 1 ,1 ,2 ,2-T ETRACH LORO- 1 ,2-DIFLUORO

C2CL3F3 1 ,2, 2-TR ICHLORO-1 . 1 , 2-TR I FLUOROE

CBRF3 BROMOTR I FLUORQMETHANE( 1 3B1

)

CBR2F2 D I BROMOD I FLUOROMETHANE ( 1 2B2

)

CF4 CARBON TETRAFLUORIDE( 14)

CH2F2 DIF LUOROMETHANE ( 32

)

CH3BR BROMOMETHANE

C2CL2F4 1 , 1—DICHLORO-1 ,2 ,2, 2-TETRAFLUORO

C2BR2F4 1 , 2-DI BROMOTETRAFLUOROETHANE( 1 1

C2BR2CLF3 1 , 2-DIBROMO-1—CHIQRO-1 ,2,2-TRIFL

C2H3CLF2 1—CHLORO-1 , 1-DI FLUOROETHANE( 1 42B

C2H4BR2 1 , 2-D I BROMOETHANE

C2H4F2 1 , 1-DI FLUOROETHANE (152A)

C2H5BR BROMOETHANE

C2H5I IODOETHANE

C5F12 PERFLUOROPENTANE

C6F14 PERFLUOROHEXANE

C6F14 P ER F LUORO-2-METHY LP ENTANE

C7F16 PERFLUOROHEPTANE

C8F18 PERFLUOROOCTANE

C9F20 PERFLUORONONANE

C10F22 PERFLUORODECANE

C4F8 PERFLUOROCYCLOBUTANE(C31 8)

C7F14 P ER F LUOROMETHY LCYC LOH EXANE

C6F6 PERFLUOROBENZENE

C6H4CL2 1 , 2-D I CHLOROBENZENE

C6H5BR BROMOBENZENE

C6H5CL CHLOROBENZENE

C6H5F FLUOROBENZENE

C6H5I IODOBENZENE

C10F18 PERFLUORODECALIN

CHBR3 BROMOFORM

CH2BRCL BROMOCHLOROMETHANE

CH2BR2 D I BROMOMETHANE

C3H7BR 1 —BROMOPROPANE

C3H7BR 2—BROMOPROPANE

C3H7I 1— IODOPROPANE

C3H7I 2— I ODOPROPANE

C4H9BR 1—BROMOBUTANE

C4H9BR 2-BROMOBUTANE

C4H9CL 1—CHLOROBUTANE

C4H9I 1— IODOBUTANE

C4H9I 2— IODOBUTANE

C5H1 1 CL 1—CHLOROPENTANE

C6H13BR 1-BROMOH EXANE

C7H7CL BENZYL CHLORIDE

C7H7CL O-CHLOROTOLUENE

56
608 C7H7CL M-CHLOROTOLUENE

609 C7H7CL P-CHLOROTOLUENE

610 C7H7F P-FLUOROTOLUENE

645 CBRCL3 BROMOTR I CH LOROMETHANE

646 C2H4F2 1 , 2—D I FLUOROETHANE

647 C2H3BR3 1 , 1 , 2-TR I BROMOETHANE

648 C2H2BR4 1,1,2, 2-TETRABROMOETHANE

649 C2H3BR VINYL BROMIDE

715 C7H7BR O-BROMOTOLUENE

716 C7H7BR M-BROMOTOLUENE

717 C7H7BR P-BROMOTOLUENE

726 C5H10CL2 1 , 5-DICHLOROPENTANE

727 C6H13CL 1—CHLOROHEXANE

732 C6H4F2 1 , 3—C I FLUOROBENZENE

733 C6H4F2 1 ,4-D I FLUOROBENZENE

734 C7H7F O-FLUOROTOLUENE

735 C7H7F M-FLUOROTOLUENE

736 C6H4CL2 1 ,3-DICHLOROBENZENE

737 C6H4CL2 1 ,4-D I CHLOROBENZENE

738 C6H3CL3 1 ,2,3-TRICHLOROBENZENE

739 C6H3CL3 1 ,2,4-TRICHLOROBENZENE

740 C6H3CL3 1 ,3,5-TRICHLOROBENZENE

741 C10H7CL 1—CHLORONAPHTHALENE

742 C6H4BR2 1 , 2-DIBROMOBENZENE

743 C6H4BR2 1 , 4-D I BROMOBENZENE

744 C10H7BR 1 -BROMONAPHTHALENE

823 C6HF5 PENTAFLUOROBENZENE

824 C7F8 PERFLUOROTOLUENE

834 C6H4F2 1 ,2-D I FLUOROBENZENE

835 C6H3F3 1 , 3. 5-TR I FLUOROBENZENE

836 C10H7F 1 -FLUORONAPHTHALENE

C + H

1 + 0 COMPOUNDSC3H60 ACETONE

23 C28H4604 DIDECYL PHTHALATE

27 C10H10O4 DIMETHYL PHTHALATE

29 C12H2402 LAURIC ACID

39 C3H80 PROPAN-2—OL

40 C6H140 DI-ISOPROPYL ETHER

54 C8H180 OCTAN-1 —OL

59 C3H80 PROPAN- 1-OL

64 C2H40 ACETALDEHYDE

65 C3H40 ACROLEIN

67 C3H60 PROP-2-ENE-1 —OL

71 C4H80 METHYL ETHYL KETONE

72 C8H180 DI-N—BUTYL ETHER

73 C4H80 BUTYRALDEHYDE

74 C6H1202 CAPROIC ACID

76 C6H10O2 CAPRO LACTONE

79 C4H60 CROTONALDEHYDE

81 C6H10O CYCLOHEXANONE

82 C16H2204 D I BUTYL PHTHALATE

84 C6H1402 1 , 1 -D I ETHOXYETHANE

87 C12H1404 DIETHYL PHTHALATE

88 C24H3804 DI-ISOOCTYL PHTHALATE

90 C4H10O2 ETHYLENE GLYCOL MONOETHYL ETHER

91 C6H1203 2-ETHOXYETHYL ACETATE

92 C5H80 3-ETHYL ACROLEIN

93 C2H60 ETHANOL

96 C2H602 ETHYLENE GLYCOL

97 C4H10O DIETHYL ETHER

99 C6H10O4 ETHYLIDENE DIACETATE

104 C6H140 HEXAN- 1-OL

106 C6H1202 ISOBUTYL ACETATE

107 C4H80 ISOBUTYRALDEHYDE

1 1 1 C2H60 METHYL ETHER

1 12 C5H80 METHYL ISOPROPENYL KETONE

113 C6H120 METHYL ISOBUTYL KETONE

119 C5H10O METHYL N-PROPYL KETONE

57
122 C6H60 PHENOL

123 C3H60 PROP IONALDEHYDE

125 C5H10O2 N-PROPYL ACETATE

134 C2H402 ACETIC ACID

135 C3H402 ACRYLIC ACID

136 C7H1202 BUTYL ACRYLATE

137 C4H10O BUTAN-1—OL

139 C10H22O DECAN-1—OL

140 C5H802 ETHYL ACRYLATE

142 C8H180 2-ETHYLHEXANOL

143 CH20 FORMALDEHYDE

144 C7H160 HEPTAN— 1 —OL

145 C5H10O2 ISOPROPYL ACETATE

146 CH40 METHANOL

147 C4H602 METHYL ACRYLATE

149 C9H20O NONAN— 1—0

151 CH202 FORMIC ACID

152 C3H602 PROPIONIC ACID

158 C4H802 ETHYL ACETATE

159 C10H20O2 2—ETHYLHEXYL ACETATE

160 C4H602 VINYL ACETATE

162 C3H802 PROPYLENE GLYCOL

164 C8H4-03 PHTHALIC ANHYDRIDE

167 C3H60 PROPYLENE OX I DE(1 ,2-EPOXYPROPANE

168 C6H1202 N-BUTYL ACETATE

171 C4H10O 2-METHYLPR0PAN-1-0L( ISOBUTANOL)

172 C4H10O BUTAN-2-0 L ( S ECBUTANO L

)

173 C4H10O 2-METHYLPROPAN-2-OL(TERTBUTANOl)

174 C3H602 METHYL ACETATE

175 C7H1403 ETHYL 3-ETHOXY PROPIONATE

176 C5H10O3 METHYL 3-METHOXY PROPIONATE

188 C6H1402 HEXYLENE GLYCOL

189 C6H140 4—METHY L-2-P ENTANO L 190 C5H120 PENTAN-2—OL

191 C4H603 ACETIC ANHYDRIDE

192 C4H203 MALEIC ANHYDRIDE

193 C2H40 ETHYLENE OXIDE( EPOXYETHANE)

194 C4H40 FURAN

195 C9H1202 CUMENE HYDROPEROXIDE

196 C2H20 KETENE

197 C2H402 METHYL FORMATE

198 C3H602 ETHYL FORMATE

199 C5H10O2 ETHYL PROPIONATE

200 C4H802 N-BUTYRIC ACID

201 C4H802 ISOBUTYRIC ACID

203 C8H80 ACETOPHENONE (METHYL PHENYL KETO

204 C9H140 ISOPHORONE

205 C6H1203 PARALDEHYDE ( 2,4, 6-TR IMETHYL-S-TR

206 C5H80 ETHYLIDENE ACETONE

207 C6H10O MESITYL OXIDE

208 C5H1202 DIETHOXYMETHANE

210 C4H60 METHACROLEIN

213 C6H1202 DIACETONE ALCOHOL

214 C4H402 DIKETENE

215 C5H10O2 TETRAHYDROFURFURYL ALCOHOL

218 C7H1402 METHOXYHEXANONE

219 C6H10O3 ETHYL ACETOACETATE

221 C6H120 CYCLOHEXANOL

222 C9H120 2—PHENYL-2—PROPANOL

225 C15H160 P-CUMYL PHENOL

227 C4H80 TETRAHYDROFURAN

229 C3H802 ETHYLENE GLYCOL MONOMETHYL ETHER

230 C5H10O3 2-METHOXYETHYL ACETATE

358 C5H804 GLUTARIC ACID

359 C5H803 LEVULINIC ACID

363 C5H402 FURFURAL

364 C6H1402 ETHYLENE GLYCOL MONO-N-BUTYL ETH

394 C5H120 PENTAN— 1 —OL

395 C5H802 METHYL METHACRYLATE

58
397

399

402

403

404

40S

409

410

416

417

418

427

445

51 1 512

513

514

515

516

517

518

519

520

521

522

523

524

525

526

527

528

529

530

531

532

533

534

535

536

537

538

539

540

541

542

543

544

545

546

547

548

549

550

551

552

553

567

568

61

612

613

614

615

616

617

618

619

620

621

C5H120 ETHYL PROPYL ETHER

C4H10O3 DI ETHYLENE GLYCOL

C2H202 GLYOXAL

C5H802 ISOPROPENYL ACETATE

C5H802 ACETYL ACETONE

C7H80 O-CRESOL

C7H80 M—CRESOL

C7H80 P-CRESOL

C6H10O4 ADIPIC ACID

C7H602 BENZOIC ACID

C7H80 BENZYL ALCOHOL

C3H803 GLYCERINE

C3H802 DIMETHOXYMETHANE

C5H120 3—METHYLBUTAN— 1—OL

C5H120 2-METHY LBUTAN-2-0

C8H180 OCTAN-2-OL

C4H10O METHYL PROPYL ETHER

C5H120 METHYL TERTBUTYL ETHER

C6H140 DIPROPYL ETHER

C4H80 ETHYL VINYL ETHER

C5H10O ETHYL ALLYL ETHER

C5H10O DIETHYL KETONE

C5H10O METHYL ISOPROPYL KETONE

C6H120 METHYL N-BUTYL KETONE

C6H120 ETHYL N-PROPYL KETONE

C7H140 METHYL N-PENTYL KETONE

C9H180 DI-N—BUTYL KETONE

C5H10O2 N-VALERIC ACID

C5H10O2 ISOVALERIC ACID

C4H802 PROPYL FORMATE

C5H10O2 ISOBUTYL FORMATE

C6H1202 N-PENTYL FORMATE

C6H1202 ISOPENTYL FORMATE

C7H1402 ISOPENTYL ACETATE

C4H802 METHYL PROPIONATE

C6H1202 N-PROPYL PROPIONATE

C7H1402 ISOBUTYL PROPIONATE

C5H10O2 METHYL BUTYRATE

C5H10O2 METHYL ISOBUTYRATE

C6H1202 ETHYL BUTYRATE

C6H1202 ETHYL ISOBUTYRATE

C7H1402 N-PROPYL BUTYRATE

C7H1402 N-PROPYL ISOBUTYRATE

C8H1602 ISOBUTYL BUTYRATE

C6H1202 METHYL VALERATE

C7H1402 ETHYL VALERATE

C10H20O2 ETHYL OCTANOATE (CAPRYLATE)

Cl 1H2202 ETHYL NONANOATE (PELARGONATE)

C13H2602 METHYL LAURATE

C8H1404 DIETHYL SUCCINATE

C8H803 METHYL SALICYLATE

C10H14O THYMOL (P-CYMEN-3—OL)

C10H20O MENTHOL

C7H80 ANISOLE(METHYL PHENYL ETHER)

C8H10O PHENETOLE( ETHYL PHENYL ETHER)

C7H60 BENZALDEHYDE

C5H10O TETRAHYDROPYRAN

C4H802 1 , 4—D I OXAN

C6H1404 TRI ETHYLENE GLYCOL

C8H1602 CAPRYLIC ACID

C7H1402 N-PENTYL ACETATE

C8H1602 N-HEXYL ACETATE

C9H1802 N-HEPTYL ACETATE

C10H20O2 N-OCTYL ACETATE

C12H2402 N-DECYL ACETATE

C7H1402 N-BUTYL PROPIONATE

C8H1602 N-PENTYL PROPIONATE

C9H1802 N-PENTYL N-BUTYRATE

C8H1602 N-PROPY L-N-VA LERAT E

59
622

623

624

626

650

651

652

653

654

655

656

657

658

659

660

661

662

663

664

665

666

667

668

669

670

671

672

673

674

675

676

677

678

688

689

690

691

692

693

694

695

696

697

698

699

700

701

708

709

710

71 1 712

713

718

719

720

721

722

730

745

746

747

748

749

750

751

752

753

754

C9H1802 ISOBUTYL VALERATE

C7H1402 METHYL-N-CAPROATE

C22H4402 BUTYL STEARATE

C5H120 2-METHYLBUTAN-1—OL

Cl 1H240 UNDECAN-1—OL

C12H260 DODECAN-1—OL

C16H340 HEXADECAN-1—OL

C18H380 OC T AD ECAN- 1 —0 L C5H10O VALERALDEHYDE

C7H140 HEPTANAL

C8H160 OCTANAL

C6H120 METHYL SECBUTYL KETONE

C6H120 ETHYL ISOPROPYL KETONE

C6H120 METHYL TERTBUTYL KETONE

C7H140 ETHYL BUTYL KETONE

C7H140 DIPROPYL KETONE

C7H140 PROPYL ISOPROPYL KETONE

C7H140 DI-ISOPROPYL KETONE

C8H160 METHYL N-HEXYL KETONE

C9H180 METHYL N-HEPTYL KETONE

C9H180 DI-ISOBUTYL KETONE

C6H10O ISOMESITYL OXIDE

C7H1402 N-HEPTANOIC ACID

C9H1802 N—NONANOIC ACID

C10H20O2 N—DECANOIC ACID

Cl 1H2202 N-UNDECANOIC ACID

C13H2602 N-TR I DECANOIC ACID

C14H2802 MYRISTIC ACID

C15H30O2 N-PENTADECANOIC ACID

C16H3202 PALMITIC ACID

C17H3402 MARGARIC ACID

C18H3602 STEARIC ACID

C22H4402 BEHENIC ACID

C16H2204 DI-ISOBUTYL PHTHALATE

C24H3804 DI (2-ETHYLHEXYL) PHTHALATE

C8H802 METHYL BENZOATE

C9H10O2 ETHYL BENZOATE

C8H1802 ETHYLENE GLYCOL MONO-N-HEXYL ETH

C4H10O2 ETHYLENE GLYCOL DIMETHYL ETHER

C6H1402 ETHYLENE GLYCOL DIETHYL ETHER

C10H22O2 ETHYLENE GLYCOL D I-N-BUTYL ETHER

C5H1203 DI ETHYLENE GLYCOL MONOMETHYL ETH

C6H1403 DI ETHYLENE GLYCOL MONOETHYL ETHE

C8H1803 DI ETHYLENE GLYCOL MONO-N-BUTYL E C6H1403 DI ETHYLENE GLYCOL DIMETHYL ETHER

C8H1803 DI ETHYLENE GLYCOL DIETHYL ETHER

C12H2603 DI ETHYLENE GLYCOL D I-N-BUTYL ETH

C5H10O CYCLOPENTANOL

C7H140 CYCLOHEPTANOL

C8H160 CYCLOOCTANOL

C5H80 CYCLOPENTANONE

C7H120 CYCLOHEPTANONE

C8H140 CYCLOOCTANONE

C6H140 ETHYL N-BUTYL ETHER

C8H180 DI-ISOBUTYL ETHER

C8H180 DI-TERTBUTYL ETHER

C10H22O DI-N-PENTYL ETHER

C10H22O DI-ISOPENTYL ETHER

C3H402 VINYL FORMATE

C5H10O2 N-BUTYL FORMATE

C7H1402 N-HEXYL FORMATE

C8H1602 N-HEPTYL FORMATE

C9H1802 N-OCTYL FORMATE

C9H1802 N-HEXYL PROPIONATE

C10H20O2 N-HEPTYL PROPIONATE

Cl 1H2202 N-OCTYL PROPIONATE

C8H1602 N-BUTYL BUTYRATE

C10H20O2 N-HEXYL BUTYRATE

Cl 1H2202 N-HEPTYl BUTYRATE

60
755 C12H2402 N-OCTYL BUTYRATE

756 C9H1802 N-BUTYL VALERATE

757 C10H20O2 N-PENTYL VALERATE

758 Cl 1H2202 N-HEXYL VALERATE

759 C12H2402 N-HEPTYL VALERATE

760 C13H2602 N-OCTYL VALERATE

798 C8H10O 2 ,5-XYLENOL

799 C8H10O 3,4—XYLENOL

800 C8H10O 3 , 5-XYLENOL

801 C12H10O DIPHENYL ETHER

829 C10H20O DECANAL

837 C6H10O3 PROPIONIC ANHYDRIDE

838 C8H1403 BUTYRIC ANHYDRIDE

847 C6H10O4 DIETHYL OXALATE

856 C6H602 CATECHOL

857 C7H802 GUAIACOL

858 C10H8O

IITROGEN COMPOUNDS

1-NAPHTHOL

50 C5H9NO 1 —METHYL-2-PYRROLI DONE

51 N2 NITROGEN

69 C6H15N3 AMINO-ETHYL PIPERAZINE

70 NH3 AMMONIA

75 C6H1 1 NO CAPROLACTAM

85 C4H10N2 DIETHYLENEDIAMINE

86 C4H13N3 DIETHYLENETRIAMINE

95 C2H8N2 ETHYLENE DIAMINE

100 CH3NO FORMAMIDE

102 C6H16N2 1 , 6-HEXANEDI AMINE

108 C10H22N2 I SOPHORON ED I AM I N E 124 C3H5N PROPIONITRI LE

127 C8H23N3 TETRAETHYLENEPENTAMINE

129 C6H18N4 TRI ETHYLENETETRAMINE

138 C12H21N02 1 1-CYANOUNDECANOIC ACID

150 C13H21N02 1 , 1-PEROXYDICYCLOHEXYLAMINE

156 C4H7N0 ACETONE CYANOHYDRIN

157 Cl 2H25N02 1 2-AM I NODOD ECANO I C ACID

161 C4H5N0 ACROLEIN CYANOHYDRIN

165 C5H5N PYRIDINE

166 C6H7N 4—METHYLPYRIDINE(GAMMA-PICOLINE)

169 C3H5NO LACTONITRILE

179 HCN HYDROGEN CYANIDE

180 C2H3N ACETONITRILE (ETHANENITRI LE)

181 C3H3N ACRYLONITRILE

202 C7H9N BENZYLAMINE

209 C3H7NO DIMETHYL FORMAMIDE

216 C3H9N TRIMETHYLAMINE

217 C6H15N TRI ETHYLAMINE

226 C5H5N 1 -CYANOBUTAD I ENE

356 C4H12N20 AMINO-ETHYL ETHANOLAMINE

360 C3H3NO OXAZOLE

361 C4H5N CROTON I TR I LE( TRANS)

378 C3H7NO 2—N I TROPROPANE

398 C2H7NO ETHANOLAMINE

41

C4H1 IN DI ETHYLAMINE

413 NO NITRIC OXIDE

414 N02 NITROGEN DIOXIDE

415 C6H7N ANI LINE

419 C10H15N N , N-DI ETHYLANI LINE

421 C6H5N02 NITROBENZENE

422 C2H7N ETHYLAMINE

423 C2H7N DIMETHYLAMINE

424 C6H13N CYCLOHEXYLAMINE

425 C6H8N2 ADIPONITRILE

426 C5H1 IN PIPERIDINE

428 C3CL3N3 CYANURIC CHLORIDE

429 C6H8N2 PHENYLHYDRAZ INE

430 C9H6N202 TOLUENE-2, 4-D I ISOCYANATE

459 N2H4 HYDRAZINE

61
461

554

555

556

557

558

559

560

561

562

563

564

565

566

569

577

625

627

679

680

681

682

683

684

685

686

687

703

714

723

724

725

728

731

761

762

763

764

765

766

767

768

769

770

771

772

773

774

775

776

777

802

803

804

805

806

807

808

809

810

81

816

817

818

819

820

821

822

831

N204 DINITROGEN TETROXIDE

CH5N METHYLAMINE

C3H9N N-PROPY LAM I NE

C3H9N ISOPROPYLAMINE

C4H1 IN N-BUTYLAMI NE

C6H15N D

I -N-PROPY LAM I NE

C4H7N BUTYRON I TR I LE

C6H1 IN CAPRONITRILE (HEXANONI TRI LE)

C7H9N N-METHYLANI LINE

C8H1 IN N , N-DIMETHYLANI LINE

C8H1 IN N-ETHYLANI LINE

C9H13N N , N-D I METHYL-O-TOLU I D I NE

C7H5N BENZONITRILE

C8H7N P-TOLUNITRILE

C4H9N PYRROLIDINE

CH3N02 NITROMETHANE

C4H1 IN I SOBUTYLAMINE

C12H27N TR I -N—BUTY LAM I NE

C5H13N N—PENTYLAMINE

C6H15N N-HEXYLAMI NE

C6H15N DI-ISOPROPYLAMINE

C7H17N N-HEPTYLAMINE

C8H19N N—OCTYLAMINE

C8H19N DI-N-BUTYLAMINE

C8H19N DI-I SOBUTYLAMINE

C9H21N TRI PROPYLAMINE

C3H7N ALLYLAMINE

C5H4CLN 2—CH LOROPYR I D I NE

C5H1 IN CYC LOPENTYLAMINE

C7H7N02 2-NI TROTOLUENE

C7H7N02 3-N I TROTOLUENE

C7H7N02 4-N I TROTOLUENE

C9H13N N , N-D I METHY L-P-TO LU I D I N E

C4H9N0 MORPHOLINE

C10H9N 1-NAPHTHYLAMINE

C10H9N 2-NAPHTHYLAMI NE

C13H13N N-METHYLD I PHENYLAMI NE

C14H15N DIBENZYLAMINE

C8H7N PHENYLACETONITRILE

C8H7N O-TOLUNITRILE

C8H7N M-TOLUNITRILE

C12H10N2 AZOBENZENE

C7H9N0 O-ANISIDINE

C8H1 1 NO O-PHENETIDINE

C8H9NO ACETANILIDE

C8H9N02 2-NITROETHYLBENZENE

C6H4N204 1 , 3-D I NITROBENZENE

C6H3N306 1 ,3,5-TRINITROBENZENE

C6H6CLN 2-CH LOROAN I L I NE

C6H6CLN 3—CH LOROAN I L I N E C6H6CLN 4—CH LOROAN I L I NE

C7H9N 0—TOLUIDINE

C7H9N M-TOLUIDINE

C7H9N P-TOLUIDINE

C4H5N PYRROLE

C6H7N 2—METHYLPYRIDINE(ALPHA-PICOLINE)

C6H7N 3-METHY LPYR I D I NE ( BETA-P ICOL I NE

)

C7H9N 2 , 4—DIMETHYLPYRIDINE(2 , 4— LUTIDIN

C7H9N 2 , 6-DIMETHYLPYRIDINE(2 , 6-LUTIDIN

C9H7N QUINOLINE

C9H7N ISOOUINOLINE

C10H9N QUINALDINE (2-METHY LOU I NOLINE)

C10H9N LEPIDINE ( 4—METHY LQU I NO L I N E

)

C10H9N 6-METHY LOU I NOLINE

C10H9N 8-METHYLQU I NOL I NE

C8H1 IN 2 , 6-DIMETHYLANILINE

C8H1 IN 4— ETHYLANI LINE

C12H1 IN DIPHENYLAMINE

C7H9N 2-ETHYLPYRIDINE

62
832 C7H9N 4-ETHYLPYR I D INE

833 C8H1 IN 2.4,6-COLLIDINE

842 C4H 1 1 N02 DIETHANOLAMINE

843 C6H15N03 TRIETHANOLAMINE

844 C2H5N02 NITROETHANE

845 C3H7N02 1 —N I TROPROPANE

846 C4H9N02 1-NITROBUTANE

854 C6H5N03 2-NITROPHENOL

855 C6H5N03 4-NITR0PHEN0L

SULFUR COMPOUNDS

163 H2S HYDROGEN SULPHIDE

228 S02 SULPHUR DIOXIDE

365 CS2 CARBON DISULPHIDE

373 CH4S METHANETHIOL

374 C2H6S ETHYL MERCAPTAN ( ETHANETHIOL)

375 COS CARBONYL SULPHIDE

452 CS CAESIUM

454 S SULPHUR

462 S03 SULPHUR TRIOXIDE

464 SF6 SULPHUR HEXAFLUORIDE

470 SNCL4 STANNIC CHLORIDE

570 C2H6S DIMETHYLSULPHIDE

571 C3H8S ETHYLMETHYLSULPHIDE

572 C4H10S DIETHYLSULPHIDE

573 C10H22S DI-ISOPENTYLSULPHIDE

574 C4H10S2 D I ETHYLD I SULPHIDE

575 C4H10O3S DIETHYL SULPHITE

778 C3H8S PROPANE- 1 -THIOL

779 C3H8S PROPAN E-2-TH I OL

780 C4H10S BUTANE-1 -THIOL

781 C4H10S 2—METHYLPROPANE-1 -TH I OL

782 C4H10S 2—METHYLPR0PANE-2-THI0L

783 C5H12S PENTANE-1 -THIOL

784 C5H12S PENTANE-2-THI0L

785 C5H12S 2-METHYLBUTANE-2-THI0L

786 C6H14S HEXANE- 1 -THIOL

787 C6H14S HEXANE-2-THI0L

788 C7H16S HEPTANE-1 -THIOL

789 C8H18S OCTANE— 1 -THIOL

790 C2H60S DIMETHYLSULPHOXIDE

791 C4H802S SULPHOLANE

812 C4H4S THIOPHENE

813 C4H8S TETRAHYDROTHIOPHENE

848 C6H6S BENZENETHIOL

849 C5H6S 2-METHYLTHIOPHENE

850 C5H6S 3-METHYLTHIOPHENE

MISCELLANEOUS COMPOUNDS

3 AIR

4 ALPHANOL

13 CO CARBON MONOXIDE

21 C6H120CL2 D I CHLORO-D I ISOPROPYL ETHER

38 H2 HYDROGEN (NORMAL)

55 02 OXYGEN

63 H20 WATER

77 C02 CARBON DIOXIDE

105 H202 HYDROGEN PEROXIDE

141 T0H20O2 2-ETHYLHEXYL ACRYLATE

154 CL2 CHLORINE

155 HCL HYDROGEN CHLORIDE

362 AR ARGON

380 HI HYDROGEN IODIDE

381 C2H0CL3 CHLORAL

386 C3H50CL EPICHLOROHYDRIN

396 HF HYDROGEN FLUORIDE

400 KR KRYPTON

401 XE XENON

405 C3H60CL2 2-3-D I CH LOROPROPANOL

63
407

420

444

446

447

448

449

450

451

453

455

456

457

458

460

463

465

466

467

468

469

471

472

473

474

576

578

579

580

581

582

583

584

585

586

587

588

589

590

729

839

840

841

851

852

853

C6H120CL2 DI-(3-CHL0R0PR0PYL) ETHER

C7H50CL BENZOYL CHLORIDE

C0CL2 PHOSGENE

H2 HYDROGEN (PARA)

HD HYDROGEN DEUTER IDE

D2 DEUTERIUM (NORMAL)

4HE HELIUM-4

NE NEON

RB RUBIDIUM

03 OZONE

F2 FLUORINE

BR2 BROMINE

12 IODINE

HG MERCURY

D20 HEAVY WATER

0F2 OXYGEN FLUORIDE

NBF5 NIOBIUM PENTAFLUORIDE

UF6 URANIUM HEXAFLUORIDE

BCL3 BORON TRICHLORIDE

ALCL3 ALUMINIUM TRICHLORIDE

SICL4 SILICON TETRACHLORIDE

TICL4 TITANIUM TETRACHLORIDE

HBR HYDROGEN BROMIDE

ALBR3 ALUMINIUM TRIBROMIDE

CD4 DEUTEROMETHANE

C2HF302 TRIFIUOROACETIC ACID

C4H12SI TETRAMETHYLSILANE

C8H20SI TETRAETHYLSILANE

C6H1 80S 1HEXAMETHYLD I S I LOXANE

C8H2402SI3 OCTAMETHY.LTR I S I LOXANE

C10H30O3SI4 DECAMETHYLTETRASI LOXANE

C12H3604SI5 DODECAMETHYLPENTAS I LOXANE

C14H4205SI6 TETRADECAMETHYLHEXASI LOXANE

Cl 6H4806SI7 HEXADECAMETHYLHEPTASI LOXANE

C18H5407SI8 OCTADECAMETHYLOCTAS I LOXANE

C8H2404SI

OCTAMETHYLCYCLOTETRASI LOXANE

Cl 0H30O5S 15 DECAMETHYLCYCLOPENTAS I LOXANE

K POTASSIUM

NA SODIUM

C2H3CL0 ACETYL CHLORIDE

C6H5CL0 2-CHLOROPHENOL

C6H5CL0 3—CHLOROPHENOL

C6H5CL0 4—CHLOROPHENOL

C3H2CLF50 ISOFLURANE

C3H2CLF50 ENFLURANE

C2H3CL02 CHLOROACETIC ACID

64
oooooooooooooooooooooooooooooooooo

Table A-3 Interface Routine to Access PPDS Data Module

(partial listing)

SUBROUTINE PPDS (NC. ICODE.XFRAC, I TY . I PROP , T . P , I PH , NE , I E , VP , CP , HP

)

THIS SUBROUTINE ACCESSES THE PPDS DATA BASE AS CONTAINED IN THE

ELECTRONIC DATA MODULE.

INPUTS:

NC - NUMBER OF COMPONENTS IN THE STREAM (NC = 1—20)

ICODE - ARRAY OF INTEGERS SPECIFYING THE PPDS CODE NUMBER

FOR EACH PURE COMPONENT IN THE STREAM

XFRAC - COMPOSITION (MOLE FRACTION) OF THE STREAM; REAL

ARRAY OF DIMENSION 20

I TY - CODE FOR TYPE OF PROPERTY REQUESTED:

ITY = -1 — TEMPERATURE DEPENDENT PROPERTY WITH PHASE UNkNOWN

ITY = 0 — CONSTANT (TEMPERATURE-INDEPENDENT PROPERTY)

ITY = 1 — TEMPERATURE-DEPENDENT PROPERTY WITH PHASE SPECIFIED

ITY = 2 — TEMPERATURE-DEPENDENT PROPERTY ALONG SATURATION LINE

IPROP - CODE FOR SPECIFIC PROPERTY (SEE TABLE A1 OR PPDS MANUAL)

FOR EXAMPLE: IPROP = 1 — MOLECULAR WEIGHT IF ITY = 0

VAPOR HEAT CAPACITY IF ITY = 1 OR 2

T - TEMPERATURE (K) (IGNORED FOR ITY = 0)

P - PRESSURE (PA) (IGNORED FOR ITY = 0 OR 2)

OUTPUTS:

I PH - PHASE INDICATOR

I PH = 1

-— LIQUID PHASE

I PH = 2 — VAPOR PHASE

I PH = 3 — PROPERTY INDEPENDENT OF PHASE

NE - NUMBER OF ERRORS

IE - CHARACTER VARIABLE ARRAY (CHARACTER* 1 IE(20)) RETURNING CODE

FOR EACH OF THE NE ERRORS

VP - VALUE OF THE REQUESTED VARIABLE PROPERTY FOR THE MIXTURE

CP - ARRAY OF THE REQUESTED CONSTANT PROPERTY (ONE ARRAY ELEMENT

FOR EACH COMPONENT OF THE MIXTURE)

HP - ARRAY OF CHARACTER VARIABLES RETURNING THE NAME AND FORMULA

FOR EACH COMPONENT OF THE MIXTURE (CHARACTER*44 HP(20))

65
APPENDIX B - OPTIMIZATION TECHNIQUE

For the determination of the optimum pipe diameter for the pumped

system and the optimum allocation of pressure drop for the capillary

system, a Fibonnaci search technique is used. This technique is only

applicable for a function, f, having a single extremum within the known

interval, [X0 , Xx ]

. The function f is evaluated at two values of X - X3

and X62 - where X0 < X3

< X6< Xx

. If f(X38 ) is greater than f(X62 )

then the maximum in f must lie in the interval X0 < X < X62 . If, on the

other hand, f(X38 ) is less than f(X62 ) the maximum must lie within

X3

< X < Xx

. The size of the interval containing the solution is thus

reduced, with X3becoming the new X0 or X62 becoming the new Xx .

The power of the Fibonnaci technique lies in the selection of the

values of X at which to evaluate f(X)

these points lie at approximately

38% and 62% of the distance between X0 and Xx :

The constant G is the so-called golden ratio and is equal to 0.61803. (This

optimization technique is also known as the golden search method.) This

constant has the property:

This means that when the original interval [X0 , Xx ] is reduced to [X0 , X62 ]

the old X3

becomes the new X62 and thus f(X62 ) does not need to be

recalculated. Likewise, when the original interval is reduced to

[X38 , X: ] the old X62 is equal to the new X3as defined by Eqn. B-2. This

ability to 'reuse' previous function evaluations speeds convengence and allows

the Fibonnaci search to locate the extremum within an interval

X38 = X0 + (1 - G) (Xx - X0 ) [B-l]

[B-2]

G

2 = (1 - G) [B-3]

66
of size (X-l - X0 )Gn_1 where (X: - X0 ) is the original interval containing

the extremum and N is the number of function evaluations.

The Fibonnaci search is implemented as a subroutine, called GOLD,

which returns the location and value of the extremum (either a minimum or

maximum) given a starting interval and an external function GEVAL which

returns a value of f(X) for a given guess of X. As an example, for the

optimization of pipe diameter, GEVAL would return the system weight for a

given value of pipe diameter. The use of subroutine GOLD is described in

comment statements in the program listing, given as Table B-l.

67
oooooooooooooooooooooo

Table B-l Subroutine to Implement Fibonnaci Search Optimization Technique

SUBROUTINE GOLD ( X0 1

, X 1 I , NC , LMAX , GEVAL , XOPT , YOPT

)

SUBROUTINE WHICH CARRIES OUT A FIBONNACI (GOLDEN) SEARCH

TECHNIQUE TO LOCATE AN EXTREMUM (MAXIMUM OR MINIMUM) IN A

FUNCTION WITHIN A SPECIFIED INTERVAL.

INPUTS:

X0I - LOWER BOUND OF INTERVAL. CONTAINING EXTREMUM

XII - UPPER BOUND OF INTERVAL CONTAINING EXTREMUM

NC - NUMBER OF FUNCTION EVALUATIONS; THE EXTREMUM IS

LOCATED WITHIN AN INTERVAL OF (XI I-X0I ) • (0 . 61 8) **NCC

LMAX - LOGICAL FLAG; IF LMAX:

.TRUE. - LOCATE MAXIMUM VALUE

.FALSE. - LOCATE MINIMUM VALUE

EXTERNAL FUNCTION:

GEVAL - RETURNS VALUE OF FUNCTION TO BE OPTIMIZED GIVEN

VALUE OF INDEPENDENT VARIABLE X

OUTPUTS:

XOPT - LOCATION OF EXTREMUM

YOPT - VALUE OF FUNCTION AT EXTREMUM

EXTERNAL GEVAL

LOGICAL LMAX

DATA GR/0 . 6 1 803398875/

X0=X0I

X 1 =X 1 I IF (LMAX) THEN

XMAX=1 .0

ELSE

XMAX=— 1 .0

END IF

X62=X0+GR* (X1-X0)

Y62=XMAX*GEVAL(X62)

DO 200 I G= 1 , NC

X38=X0+( 1 . 0—GR ) *( X 1 —X0)

Y38=XMAX -GEVAL (X38)

IF (Y62.LT.Y38) THEN

X1=X62

X62=X38

Y62=Y38

ELSE

X0=X 1 X1=X38

END IF

200 CONTINUE

XOPT=0 . 5- (X0+X1

)

YOPT=XMAX*MAX ( Y38 , Y62

)

RETURN

END

68
APPENDIX C - SELECTED REFERENCES FOR FLUID PROPERTIES

Listed below are references for the thermodynamic and transport

properties of the ten 'preferred' fluids identified in this study. Most

of the references selected include comprehensive evaluations of experimental

data from many laboratories and include convenient tabulations and/or

mathematical fits to the data.

General references

ASHRAE Handbook of fundamentals, American Society of Heating, Refrigerating

and Air Conditioning Engineers, Atlanta, GA, 1985. (This is a convenient

reference to all of the preferred fluids except methylamine and R32.

The thermodynamic formulations have been recently updated, and are

generally good; the transport properties, however, are out of date and

in some cases seriously in error. A project to update the transport

properties should be complete by 1990.)

ASHRAE Thermodynamic Properties of Refrigerants, American Society of

Heating, Refrigerating and Air Conditioning Engineers, Atlanta, GA,

1988. (Contains more extensive tabulations of formulations in the

ASHRAE Handbook of Fundamentals .

)

Encyclopedia des Gaz (Gas Encyclopedia, English translation by N. Marshall)

Elsevier, Amsterdam, the Netherlands, 1976. (A good source of materials

compatibility data on all ten preferred fluids; thermodynamic and

transport data are not always up to date.)

W. Braker and A.L. Mossman, Matheson Gas Data Book, Matheson, Division of

Searle Medical Products USA, Inc., Lyndhurst, NJ , 1980. (A good source

of materials compatibility data and safe handling recommendations; also

contains information on availability of ultra-pure materials.)

T.E. Daubert and R.P. Danner 'Data Compilation - Tables of Properties of

Pure Compounds,' Design Institute for Physical Property Data (DIPPR)

,

American Institute of Chemical Engineers, New York, NY, 1985. (Gives

convenient empirical fits to saturation properties for several hundred

compounds .

)

References for specific fluids:

ammonia (thermodynamic properties):

L. Haar and J.S. Gallagher, Thermodynamic Properties of Ammonia, J. Phys

Chem. Ref. Data 7 635-792 (1978).

69
ammonia (transport properties)

Daubert and Danner (see reference above)

propane and iso-butane (thermodynamic and transport):

B.A. Younglove and J.F. Ely 'Thermophysical Properties of Fluids, II.

Methane, Ethane, Propane, Isobutane and Normal Butane,' J. Phys . Chem.

Ref. Data 16 577-798 (1987).

methylamine (thermodynamic and transport)

Daubert and Danner (see reference above)

R32 (thermodynamic)

P.F. Malbrunot, P.A. Meunier, G.M. Scatena, W.H. Mears , K.P. Murphy and

J.V. Sinka 'Pressure-Volume-Temperature Behavior of Difluorome thane ,

Journal of Chemical and Engineering Data 13 16-21 (1968).

R32 (transport)

T.W. Phillips and K.P. Murphy, 'Liquid Viscosity of Halocarbons ,

Journal of Chemical and Engineering Data 15 304-307 (1970).

W. Tauscher, 'Measurement of the Thermal Conductivity of Liquid Refrigerant

by an Unsteady-State Hot Wire Method,' ASHRAE Journal, 11(1) 97-104 (1969).

R152a (thermodynamic)

ASHRAE Handbook of Fundamentals (see reference above).

3 R152a (transport):

'Thermophysical Properties of Refrigerants,' 2nd ed. American Society of

Heating, Refrigerating and Air Conditioning Engineers, Atlanta, GA, 1976.

(As noted above, the current edition of this reference is not always the

most reliable but it will be updated by 1990.)

R22 (thermodynamic and transport)

'Thermal Properties of Refrigerant - R22, Chlorodif luorome thane Japanese

Association of Refrigeration, 1975. (The thermodynamic, but not transport,

formulations in this work have been adopted by ASHRAE.)

Halon 1301 (thermodynamic and transport)

ASHRAE Handbook of Fundamentals (see reference above).

R12 (thermodynamic and transport)

'Thermophysical Properties of Refrigerants - R12, Dichlorodifluorome thanes

,

Japanese Association of Refrigeration, 1981. (The thermodynamic, but not

transport, formulations in this work have been adopted by ASHRAE.)

Rll (thermodynamic)

ASHRAE Thermodynamic Properties of Refrigerants (see reference above)

70
Rll (thermodynamic and transport)

V.V. Altunin, V.Z. Geller, E.A. Kremenevskaya , I. I. Perelshtein and

E.K. Petrov, 'Thermophysical Properties of Freons, Methane Series,

Part 2,' Hemisphere Publishing Corporation, Washington, DC, 1987„

(translation of ' Teplofizichesklye Svoystva Freonov, Vol. 2

r Monograph

Series of the National Standard Reference Data Service of the USSR, 1985) . Note: heat transfer coefficients are relative to the values for ammonia.

71
BS-114A (REV. 2-80

U.S. DEPT. OF COMM.

BIBLIOGRAPHIC DATA

SHEET (See instructions)

1. PUBLICATION OR

REPORT NO.

NB SIR 88-3812

2. Performing Organ. Report No. 3. Publication Date

AUGUST 1988

». TITLE AND SUBTITLE

Working Fluid Selection for Spaced-Based Two-Phase Heat Transport Systems

5. AUTHOR(S)

Mark 0. McLinden

>. PERFORMING ORGANIZATION (If joint or other than NBS, see in struction s)

national bureau of standards

DEPARTMENT OF COMMERCE

WASHINGTON, D.C. 20234

7. Contract/Grant No.

8. Type of Report & Period Covered

). SPONSORING ORGANIZATION NAME AND COMPLETE ADDRESS (Street, City, State, ZIP)

National Aeronautics and Space Administration

Goddard Space Flight Center

0. SUPPLEMENTARY NOTES

j Document describes a computer program; SF-185, FIPS Software Summary, is attached.

i. ABSTRACT (A 200-word or less factual summary of most significant information. If document includes a si gnificant

bi bl iography or literature survey, mention it here)

The working fluid for externally-mounted space-based two-phase heat transport

systems is considered. A sequence of screening criteria involving freezing and

critical point temperatures and latent heat of vaporization and vapor density are

applied to a data base of 860 fluids. The thermal performance of the 52 fluids

which pass this preliminary screening are then ranked according to their impact,

on the weight of a reference system. Upon considering other non-thermal criteria

(flammability, toxicity and chemical stability) a final set of 10 preferred fluids

is obtained. The effects of variations in system parameters is investigated for

these 10 fluids by means of a factorial design.

2. KEY WORDS ( Six to twelve entries ; alphabetical order; capitalize only proper names; and separate key words by semicolons)

cold plate, fluid properties, heat transport, refrigerants

,

working fluids

3. AVAILABILITY

[^(j Uni i mi ted

For Official Distribution. Do Not Release to NTIS

Order From Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. “ 20402.

[X~! Order From National Technical Information Service (NTIS), Springfield, VA. 22161

14. NO. OF

PRINTED PAGES

75

15. Price

$13.95

USCOMM-DC 6043-P80