244

P-PROPATH: Pure Substances and Mixtures with Fixed Composition

2.25 Ethylene
Equations for thermodynamic properties have been cited from Jahangiri et al. [1], one for viscosity from Makita
et al.[2] and one for surface tension from Miller et al.[3].

2.25.1 Temperature Scale
International practical temperature scale 1968 (IPTS-1968)

2.25.2 The Names of Substance, Library File and Single Shot Program
Name of Substance:
Library File for UNIX:
Library File for DOS,Windows95/NT:
Single Shot Program for UNIX:
Single Shot Program for DOS,Windows95/NT:

Ethylenelibjc2h4.aJC2H4.LIB
c2h4-ss
C2H4–SS.EXE

2.25.3 Important Constants and Others
Molecular Formula:
Relative Molecular Mass:
Gas Constant:

C2 H4
28.054296.37 J/(kg·K)

Critical Constants:
Critical Pressure:
Critical Temperature:
Critical Speciﬁc Volume:

5.0401×10 6Pa (50.401 bar)282.3452 K (9.1952 ◦C)
4.8405×10 −3m3 /kg

Triple Point:
Pressure:
Temperature:

122.5 Pa (1.225×10 −3bar)
103.986 K (−169.164 ◦C)

Reference State:
At 1.01325 bar (1 atm) and 25◦C(298.15 K), 0 J/(kg·K) is assigned to the speciﬁc entropy of the ideal gas. At
25◦ C(298.15 K), 0 J/kg is assigned to the speciﬁc enthalpy of the ideal gas.

2.25.4 Formula
Equation of State:
Equation (5.1) in a function form of A = A(ρ, T ) in reference [1]. Here A=speciﬁc helmholtz energy, ρ=density
and T =temperature.
Vapor Pressure:
Equation (3.1) in reference [1].
Properties at Vapor-Liquid Equilibrium:
Equation (5.1) in reference [1] for speciﬁc volume. Equations (5.13) and (5.14) in reference [1] for speciﬁc
entropy and speciﬁc enthalpy, respectively. Equations (5.16) and (5.17) in reference [1] for isochoric speciﬁc heatand isobaric speciﬁc heat, respectively.
Transport Properties:
Viscosity from equation (4) in reference [2].
The Other Properties:

Ethylene

245

Surface tension from reference [3].

References[1] M.Jahangiri, R.T.Jacobsen, R.B.Stewart and R.D.McCarty, J. Phys. Chem. Ref. Data, 15-2,(1986),
pp.593-734.
[2] T.Makita, Y.Tanaka and A.Nagashima, Rev. Phys. Chem. Japan, 44-2,(1974), pp.98–111; 46–1, (1976),
pp.54-55.
[3] J.W.Miller,Jr. and C.L.Yaws, Chem. Eng., 83–23, (1976), pp.127–129.

246

P-PROPATH: Pure Substances and Mixtures with Fixed Composition
Table II–2.25–1

No.
1
94

Name of
Function
AIPPT(P,T)
AJTPT(P,T)

Ethylene Function

Function and Argument(s)AJTPT: Joule-Thomson Coeﬃcient [K/Pa]P∗: Pressure [Pa], [bar]T∗: Temperature [K], [◦C]

Range of Argument(s)10000≤P≤40×106 [Pa]TMLP(P)≤T≤450 [K]
40×106 <P≤260×106 [Pa]TMLP(P)≤T≤350 [K]
0.1≤P≤400 [bar]TMLP(P)≤T≤176.85 [◦ C]
400<P≤2600 [bar]TMLP(P)≤T≤76.85 [◦ C]

8A
8B
82

AKPD(P)AKPDD(P)AKPT(P,T)

AKPT: Isentropic Exponent [–]P∗: Pressure [Pa], [bar]T∗: Temperature [K], [◦C]

10000≤P≤40×106 [Pa]TMLP(P)≤T≤450 [K]
40×106 <P≤260×106 [Pa]TMLP(P)≤T≤350 [K]
0.1≤P≤400 [bar]TMLP(P)≤T≤176.85 [◦ C]
400<P≤2600 [bar]TMLP(P)≤T≤76.85 [◦ C]

8C
8D
2

AKTD(T)
AKTDD(T)
ALAPP(P)3

ALAPT(T)4

ALHP(P)

5

ALHT(T)

6
7
8
9
10
11
12
13

ALMPD(P)ALMPDD(P)
ALMPT(P,T)
ALMTD(T)ALMTDD(T)
AMUPD(P)AMUPDD(P)AMUPT(P,T)

ALAPP: Laplace Coeﬃcient [m]P∗: Pressure [Pa], [bar]
ALAPT: Laplace Coeﬃcient [m]T∗: Temperature [K], [◦C]
ALHP: Latent Heat of Vaporization [J/kg]
P∗: Pressure [Pa], [bar]ALHT: Latent Heat of Vaporization [J/kg]
T∗: Temperature [K], [◦C]

122.5≤P<5.0401×106 [Pa]1.225×10−3 ≤P<50.401 [bar]103.986≤T<282.3452 [K]−169.164≤T<9.1952 [◦ C]
122.5≤P≤5.0401×106 [Pa]1.225×10−3 ≤P≤50.401 [bar]103.986≤T≤282.3452 [K]−169.164≤T≤9.1952 [◦ C]

AMUPT: Coeﬃcient of Viscosity [Pa·s]
P∗: Pressure [Pa], [bar]T∗: Temperature [K], [◦C]

0≤P≤80×106 [Pa]297.15≤T≤373.15 [K]0≤P≤800 [bar]24≤T≤100 [◦ C]

14
15
92

AMUTD(T)AMUTDD(T)BPPT(P,T)

BPPT: Volumetric Coeﬃcient of Expansion [1/K]
P∗: Pressure [Pa], [bar]T∗: Temperature [K], [◦C]

10000≤P≤40×106 [Pa]TMLP(P)≤T≤450 [K]
40×106 <P≤260×106 [Pa]TMLP(P)≤T≤350 [K]
0.1≤P≤400 [bar]TMLP(P)≤T≤176.85 [◦ C]
400<P≤2600 [bar]TMLP(P)≤T≤76.85 [◦ C]

Ethylene

247
Table II–2.25–1

No.
90

91

93

Name of
Function
BSPT(P,T)

BTPT(P,T)

BVPT(P,T)

16

CPPD(P)

17

CPPDD(P)18

CPPT(P,T)

19

CPTD(T)

20

CPTDD(T)21

CRP(‘A’)

Ethylene Function (cont’d)

Function and Argument(s)Range of Argument(s)BSPT: Isentropic Compressibility [1/Pa]
P∗: Pressure [Pa], [bar]T∗: Temperature [K], [◦C]

10000≤P≤40×106 [Pa]TMLP(P)≤T≤450 [K]
40×106 <P≤260×106 [Pa]TMLP(P)≤T≤350 [K]

BTPT: Isothermal Compressibility [1/Pa]
P∗: Pressure [Pa], [bar]T∗: Temperature [K], [◦C]

BVPT: Pressure Coeﬃcient [1/K]
P∗: Pressure [Pa], [bar]T∗: Temperature [K], [◦C]

CPPD: Isobaric Speciﬁc Heat of Saturated
Liquid [J/(kg·K)]
P∗: Pressure [Pa], [bar]
CPPDD: Isobaric Speciﬁc Heat of Saturated
Vapor [J/(kg·K)]
P∗: Pressure [Pa], [bar]CPPT: Isobaric Speciﬁc Heat [J/(kg·K)]
P∗: Pressure [Pa], [bar]T∗: Temperature [K], [◦C]

CPTD: Isobaric Speciﬁc Heat of Saturated
Liquid [J/(kg·K)]
T∗: Temperature [K], [◦C]
CPTDD: Isobaric Speciﬁc Heat of Saturated
Vapor [J/(kg·K)]T∗ : Temperature [K], [◦ C]
CRP: Critical Constants
H: ‘A’=‘H’: 0.79537×106 [J/kg] Speciﬁc EnthalpyP∗: ‘A’=‘P’: 5.0401×106 [Pa], 50.401 [bar] Pressure
S: ‘A’=‘S’: 5.8587×103 [J/(kg·K)] Speciﬁc EntropyT∗: ‘A’=‘T’: 282.3452 [K], 9.1952 [◦ C] Temperature
V: ‘A’=‘V’: 4.8405×10−3 [m3 /kg] Speciﬁc Volume

0.1≤P≤400 [bar]TMLP(P)≤T≤176.85 [◦ C]
400<P≤2600 [bar]TMLP(P)≤T≤76.85 [◦ C]
10000≤P≤40×106 [Pa]TMLP(P)≤T≤450 [K]
40×106 <P≤260×106 [Pa]TMLP(P)≤T≤350 [K]
0.1≤P≤400 [bar]TMLP(P)≤T≤176.85 [◦ C]
400<P≤2600 [bar]TMLP(P)≤T≤76.85 [◦ C]
10000≤P≤40×106 [Pa]TMLP(P)≤T≤450 [K]
40×106 <P≤260×106 [Pa]TMLP(P)≤T≤350 [K]
0.1≤P≤400 [bar]TMLP(P)≤T≤176.85 [◦ C]
400<P≤2600 [bar]TMLP(P)≤T≤76.85 [◦ C]
122.5≤P<5.0401×106 [Pa]1.225×10−3 ≤P<50.401 [bar]122.5≤P<5.0401×106 [Pa]1.225×10−3 ≤P<50.401 [bar]10000≤P≤40×106 [Pa]TMLP(P)≤T≤450 [K]
40×106 <P≤260×106 [Pa]TMLP(P)≤T≤350 [K]
0.1≤P≤400 [bar]TMLP(P)≤T≤176.85 [◦ C]
400<P≤2600 [bar]TMLP(P)≤T≤76.85 [◦ C]
103.986≤T<282.3452 [K]−169.164≤T<9.1952 [◦ C]
103.986≤T<282.3452 [K]−169.164≤T<9.1952 [◦ C]
one of ‘H’, ‘P’, ‘S’, ‘T’ and ‘V’248

P-PROPATH: Pure Substances and Mixtures with Fixed Composition
Table II–2.25–1

No.
7A
76

Name of
Function
CVPD(P)
CVPDD(P)77

CVPT(P,T)

Ethylene Function (cont’d)

Function and Argument(s)CVPDD: Isochoric Speciﬁc Heat of Saturated
Vapor [J/(kg·K)]
P∗: Pressure [Pa], [bar]CVPT: Isochoric Speciﬁc Heat [J/(kg·K)]
P∗: Pressure [Pa], [bar]T∗: Temperature [K], [◦ C]

Range of Argument(s)122.5≤P<5.0401×106 [Pa]1.225×10−3 ≤P<50.401 [bar]10000≤P≤40×106 [Pa]TMLP(P)≤T≤450 [K]
40×106 <P≤260×106 [Pa]TMLP(P)≤T≤350 [K]
0.1≤P≤400 [bar]TMLP(P)≤T≤176.85 [◦C]
400<P≤2600 [bar]TMLP(P)≤T≤76.85 [◦C]

7B
78

CVTD(T)
CVTDD(T)

2A
2B
22
2C
2D
89

EPSPD(P)EPSPDD(P)EPSPT(P,T)
EPSTD(T)EPSTDD(T)FC(‘A’)9A
96

GAMPD(P)GAMPDD(P)95

GAMPT(P,T)

CVTDD: Isochoric Speciﬁc Heat of Saturated
Vapor [J/(kg·K)]
T∗: Temperature [K], [◦ C]

103.986≤T<282.3452 [K]−169.164≤T<9.1952 [◦ C]

FC: Fundamental Constants
M: ‘A’=‘M’: 28.054 Relative Molecular Mass
R: ‘A’=‘R’: 296.37 [J/(kg·K)] Gas Constant

one of ‘M’ and ‘R’

GAMPDD: Ratio of Speciﬁc Heats of Saturated
Vapor [–]P∗: Pressure [Pa], [bar]GAMPT: Ratio of Speciﬁc Heats [–]P∗: Pressure [Pa], [bar]T∗: Temperature [K], [◦ C]

122.5≤P≤5.0401×106 [Pa]1.225×10−3 ≤P≤50.401 [bar]10000≤P≤40×106 [Pa]TMLP(P)≤T≤450 [K]
40×106 <P≤260×106 [Pa]TMLP(P)≤T≤350 [K]
0.1≤P≤400 [bar]TMLP(P)≤T≤176.85 [◦C]
400<P≤2600 [bar]TMLP(P)≤T≤76.85 [◦C]

9B
97

GAMTD(T)GAMTDD(T)23

HPD(P)

24

HPDD(P)71

HPS(P,S)GAMTDD: Ratio of Speciﬁc Heats of Saturated
Vapor [–]T∗: Temperature [K], [◦ C]
HPD: Speciﬁc Enthalpy of Saturated Liquid [J/kg]
P∗: Pressure [Pa], [bar]HPDD: Speciﬁc Enthalpy of Saturated Vapor [J/kg]
P∗: Pressure [Pa], [bar]HPS: Speciﬁc Enthalpy [J/kg]
P∗: Pressure [Pa], [bar]S: Speciﬁc Entropy [J/(kg·K)]

103.986≤T≤282.3452 [K]−169.164≤T≤9.1952 [◦ C]
122.5≤P≤5.0401×106 [Pa]1.225×10−3 ≤P≤50.401 [bar]122.5≤P≤5.0401×106 [Pa]1.225×10−3 ≤P≤50.401 [bar]10000≤P≤40×106 [Pa]SPT(P,TMLP(P))≤S≤
SPT(P,450K) [J/(kg·K)]
40×106 <P≤260×106 [Pa]SPT(P,TMLP(P))≤S≤
SPT(P,350K) [J/(kg·K)]
0.1≤P≤400 [bar]SPT(P,TMLP(P))≤S≤
SPT(P,176.85◦ C) [J/(kg·K)]
400<P≤2600 [bar]SPT(P,TMLP(P))≤S≤
SPT(P,76.85◦ C) [J/(kg·K)]

Ethylene

249
Table II–2.25–1

No.
25

Name of
Function
HPT(P,T)

26

HPX(P,X)

27

HTD(T)28

HTDD(T)

29

HTX(T,X)

84

IDENTF(‘A’)

66
68

PLDT(T)
PMLT(T)

85
86
81
87
88
99
30

PRPD(P)PRPDD(P)
PRPT(P,T)
PRTD(T)
PRTDD(T)PSBT(T)
PST(T)72
73
31

PSTD(T)
PSTDD(T)SIGP(P)

32

SIGT(T)

33

SPD(P)34

SPDD(P)35

SPT(P,T)

Ethylene Function (cont’d)

Function and Argument(s)HPT: Speciﬁc Enthalpy [J/kg]
P∗: Pressure [Pa], [bar]T∗: Temperature [K], [◦ C]

HPX: Speciﬁc Enthalpy of Mixture [J/kg]
P∗: Pressure [Pa], [bar]
X: Dryness Fraction [–]HTD: Speciﬁc Enthalpy of Saturated Liquid [J/kg]
T∗: Temperature [K], [◦ C]
HTDD: Speciﬁc Enthalpy of Saturated Vapor [J/kg]
T∗: Temperature [K], [◦ C]
HTX: Speciﬁc Enthalpy of Mixture [J/kg]
T∗: Temperature [K], [◦ C]
X: Dryness Fraction [–]IDENTF: CHARACTER TYPE FUNCTION
for Package Identiﬁcation (Length 20)
C: ‘A’=‘C’: ‘C2H4’ Molecular Formula
S: ‘A’=‘S’: ‘ETHYLENE’ Name of Substance
V: ‘A’=‘V’: ‘10.1’ Version Number

Range of Argument(s)10000≤P≤40×106 [Pa]TMLP(P)≤T≤450 [K]
40×106 <P≤260×106 [Pa]TMLP(P)≤T≤350 [K]
0.1≤P≤400 [bar]TMLP(P)≤T≤176.85 [◦ C]
400<P≤2600 [bar]TMLP(P)≤T≤76.85 [◦C]
122.5≤P≤5.0401×106 [Pa]1.225×10−3 ≤P≤50.401 [bar]0≤X≤1.0 [–]103.986≤T≤282.3452 [K]−169.164≤T≤9.1952 [◦C]
103.986≤T≤282.3452 [K]−169.164≤T≤9.1952 [◦C]
103.986≤T≤282.3452 [K]−169.164≤T≤9.1952 [◦C]
0≤X≤1.0 [–]one of ‘C’, ‘S’ and ‘V’

PMLT∗: Pressure on Melting Curve [Pa], [bar]T∗: Temperature [K], [◦ C]

103.986≤T≤135.2 [K]−169.164≤T≤−137.95 [◦ C]

PST∗: Saturation Pressure [Pa], [bar]T∗: Temperature [K], [◦ C]

103.986≤T≤282.3452 [K]−169.164≤T≤9.1952 [◦C]

SIGP: Surface Tension [N/m]P∗: Pressure [Pa], [bar]
SIGT: Surface Tension [N/m]T∗: Temperature [K], [◦ C]
SPD: Speciﬁc Entropy of Saturated Liquid[J/(kg·K)]
P∗: Pressure [Pa], [bar]SPDD: Speciﬁc Entropy of Saturated Vapor[J/(kg·K)]
P∗: Pressure [Pa], [bar]SPT: Speciﬁc Entropy [J/(kg·K)]
P∗: Pressure [Pa], [bar]T∗: Temperature [K], [◦ C]

122.5≤P≤5.0401×106 [Pa]1.225×10−3 ≤P≤50.401 [bar]103.986≤T≤282.3452 [K]−169.164≤T≤9.1952 [◦C]
122.5≤P≤5.0401×106 [Pa]1.225×10−3 ≤P≤50.401 [bar]122.5≤P≤5.0401×106 [Pa]1.225×10−3 ≤P≤50.401 [bar]10000≤P≤40×106 [Pa]TMLP(P)≤T≤450 [K]
40×106 <P≤260×106 [Pa]TMLP(P)≤T≤350 [K]
0.1≤P≤400 [bar]TMLP(P)≤T≤176.85 [◦ C]
400<P≤2600 [bar]TMLP(P)≤T≤76.85 [◦C]

250

P-PROPATH: Pure Substances and Mixtures with Fixed Composition
Table II–2.25–1

No.
36

Name of
Function
SPX(P,X)

37

STD(T)38

STDD(T)

39

STX(T,X)

67
69

TLDP(P)
TMLP(P)64

TPH(P,H)

Ethylene Function (cont’d)

Function and Argument(s)Range of Argument(s)SPX: Speciﬁc Entropy of Mixture [J/(kg·K)]
P∗: Pressure [Pa], [bar]
X: Dryness Fraction [–]STD: Speciﬁc Entropy of Saturated Liquid[J/(kg·K)]
T∗: Temperature [K], [◦ C]
STDD: Speciﬁc Entropy of Saturated Vapor[J/(kg·K)]
T∗: Temperature [K], [◦ C]
STX: Speciﬁc Entropy of Mixture [J/(kg·K)]
T∗: Temperature [K], [◦ C]
X: Dryness Fraction [–]122.5≤P≤5.0401×106 [Pa]1.225×10−3 ≤P≤50.401 [bar]0≤X≤1.0 [–]103.986≤T≤282.3452 [K]−169.164≤T≤9.1952 [◦C]

TMLP∗: Temperature on Melting Curve [K], [◦ C]
P∗: Pressure [Pa], [ bar]
TPH∗: Temperature [K], [◦ C]
P∗: Pressure [Pa], [bar]H: Speciﬁc Enthalpy [J/kg]

10000≤P≤260×106 [Pa]0.1≤P≤2600 [bar]10000≤P≤40×106 [Pa]
HPT(P,TMLP(P))≤H≤
HPT(P,450K) [J/kg]
40×106 <P≤260×106 [Pa]
HPT(P,TMLP(P))≤H≤
HPT(P,350K) [J/kg]

103.986≤T≤282.3452 [K]−169.164≤T≤9.1952 [◦C]
103.986≤T≤282.3452 [K]−169.164≤T≤9.1952 [◦C]
0≤X≤1.0 [–]0.1≤P≤400 [bar]HPT(P,TMLP(P))≤H≤
HPT(P,176.85◦ C) [J/kg]
400<P≤2600 [bar]HPT(P,TMLP(P))≤H≤
HPT(P,76.85◦ C) [J/kg]
6H
65

TPH2(P,H)
TPS(P,S)TPS∗: Temperature [K], [◦C]P∗: Pressure [Pa], [bar]S: Speciﬁc Entropy [J/(kg·K)]

10000≤P≤40×106 [Pa]SPT(P,TMLP(P))≤S≤
SPT(P,450K) [J/(kg·K)]
40×106 <P≤260×106 [Pa]SPT(P,TMLP(P))≤S≤
SPT(P,350K) [J/(kg·K)]
0.1≤P≤400 [bar]SPT(P,TMLP(P))≤S≤
SPT(P,176.85◦ C) [J/(kg·K)]
400<P≤2600 [bar]SPT(P,TMLP(P))≤S≤
SPT(P,76.85◦ C) [J/(kg·K)]

6S
98

TPS2(P,S)TPSEUP(P)70

TPV(P,V)TPSEUP: Pseudo Boiling Point [K], [◦C]P∗: Pressure [Pa], [bar]TPV∗: Temperature [K], [◦ C]
P∗: Pressure [Pa], [bar]V: Speciﬁc Volume [m3 /kg]

5.0401×106 <P≤40×106 [Pa]50.401<P≤400 [bar]10000≤P≤40×106 [Pa]VPT(P,TMLP(P))≤V≤
VPT(P,450K) [m3 /kg]
40×106 <P≤260×106 [Pa]VPT(P,TMLP(P))≤V≤
VPT(P,350K) [m3 /kg]
0.1≤P≤400 [bar]VPT(P,TMLP(P))≤V≤
VPT(P,176.85◦ C) [m3 /kg]
400<P≤2600 [bar]VPT(P,TMLP(P))≤V≤
VPT(P,76.85◦ C) [m3 /kg]

Ethylene

251
Table II–2.25–1

No.
41

Name of
Function
TRPL(‘A’)

100
40

TSBP(P)
TSP(P)

74
75
42

TSPD(P)TSPDD(P)UPD(P)43

UPDD(P)79

UPS(P,S)

44

UPT(P,T)45

UPX(P,X)

46

UTD(T)

47

UTDD(T)

48

UTX(T,X)

49

VPD(P)50

VPDD(P)

Ethylene Function (cont’d)

Function and Argument(s)Range of Argument(s)TRPL∗: Properties at Triple PointP∗: ‘A’=‘P’: 0.1225×103 [Pa], 1.225×10−3 [bar]PressureT∗: ‘A’=‘T’: 103.986 [K], −169.164 [◦C]
Temperature

one of ‘P’ and ‘T’

TSP∗: Saturation Temperature [K], [◦C]P∗: Pressure [Pa], [bar]122.5≤P≤5.0401×106 [Pa]1.225×10−3 ≤P≤50.401 [bar]UPD: Speciﬁc Internal Energy of Saturated
Liquid [J/kg]
P∗: Pressure [Pa], [bar]UPDD: Speciﬁc Internal Energy of Saturated
Vapor [J/kg]
P∗: Pressure [Pa], [bar]UPS: Speciﬁc Internal Energy [J/kg]
P∗: Pressure [Pa], [bar]S: Speciﬁc Entropy [J/(kg·K)]

122.5≤P≤5.0401×106 [Pa]1.225×10−3 ≤P≤50.401 [bar]

UPT: Speciﬁc Internal Energy [J/kg]
P∗: Pressure [Pa], [bar]T∗: Temperature [K], [◦ C]

UPX: Speciﬁc Internal Energy of Mixture [J/kg]
P∗: Pressure [Pa], [bar]
X: Dryness Fraction [–]UTD: Speciﬁc Internal Energy of Saturated
Liquid [J/kg]
T∗: Temperature [K], [◦ C]
UTDD: Speciﬁc Internal Energy of Saturated
Vapor [J/kg]
T∗: Temperature [K], [◦ C]
UTX: Speciﬁc Internal Energy of Mixture [J/kg]
T∗: Temperature [K], [◦ C]
X: Dryness Fraction [–]VPD: Speciﬁc Volume of Saturated Liquid [m3 /kg]P∗: Pressure [Pa], [bar]VPDD: Speciﬁc Volume of Saturated Vapor [m3 /kg]P∗: Pressure [Pa], [bar]122.5≤P≤5.0401×106 [Pa]1.225×10−3 ≤P≤50.401 [bar]10000≤P≤40×106 [Pa]SPT(P,TMLP(P))≤S≤
SPT(P,450K) [J/(kg·K)]
40×106 <P≤260×106 [Pa]SPT(P,TMLP(P))≤S≤
SPT(P,350K) [J/(kg·K)]
0.1≤P≤400 [bar]SPT(P,TMLP(P))≤S≤
SPT(P,176.85◦ C) [J/(kg·K)]
400<P≤2600 [bar]SPT(P,TMLP(P))≤S≤
SPT(P,76.85◦ C) [J/(kg·K)]
10000≤P≤40×106 [Pa]TMLP(P)≤T≤450 [K]
40×106 <P≤260×106 [Pa]TMLP(P)≤T≤350 [K]
0.1≤P≤400 [bar]TMLP(P)≤T≤176.85 [◦ C]
400<P≤2600 [bar]TMLP(P)≤T≤76.85 [◦ C]
122.5≤P≤5.0401×106 [Pa]1.225×10−3 ≤P≤50.401 [bar]0≤X≤1.0 [–]103.986≤T≤282.3452 [K]−169.164≤T≤9.1952 [◦ C]
103.986≤T≤282.3452 [K]−169.164≤T≤9.1952 [◦ C]
103.986≤T≤282.3452 [K]−169.164≤T≤9.1952 [◦ C]
0≤X≤1.0 [–]122.5≤P≤5.0401×106 [Pa]1.225×10−3 ≤P≤50.401 [bar]122.5≤P≤5.0401×106 [Pa]1.225×10−3 ≤P≤50.401 [bar]252

P-PROPATH: Pure Substances and Mixtures with Fixed Composition
Table II–2.25–1

No.
80

51

Name of
Function
VPS(P,S)

VPT(P,T)52

VPX(P,X)

53

VTD(T)54

VTDD(T)

55

VTX(T,X)

8E
8F
83

WPD(P)WPDD(P)
WPT(P,T)

Ethylene Function (cont’d)

Function and Argument(s)VPS: Speciﬁc Volume [m3 /kg]P∗: Pressure [Pa], [bar]S: Speciﬁc Entropy [J/(kg·K)]

VPT: Speciﬁc Volume [m3 /kg]P∗: Pressure [Pa], [bar]T∗: Temperature [K], [◦ C]

Range of Argument(s)10000≤P≤40×106 [Pa]SPT(P,TMLP(P))≤S≤
SPT(P,450K) [J/(kg·K)]
40×106 <P≤260×106 [Pa]SPT(P,TMLP(P))≤S≤
SPT(P,350K) [J/(kg·K)]
0.1≤P≤400 [bar]SPT(P,TMLP(P))≤S≤
SPT(P,176.85◦ C) [J/(kg·K)]
400<P≤2600 [bar]SPT(P,TMLP(P))≤S≤
SPT(P,76.85◦ C) [J/(kg·K)]
10000≤P≤40×106 [Pa]TMLP(P)≤T≤450 [K]
40×106 <P≤260×106 [Pa]TMLP(P)≤T≤350 [K]

VPX: Speciﬁc Volume of Mixture [m3 /kg]P∗: Pressure [Pa], [bar]
X: Dryness Fraction [–]VTD: Speciﬁc Volume of Saturated Liquid [m3 /kg]
T∗: Temperature [K], [◦ C]
VTDD: Speciﬁc Volume of Saturated Vapor [m3 /kg]
T∗: Temperature [K], [◦ C]

0.1≤P≤400 [bar]TMLP(P)≤T≤176.85 [◦C]
400<P≤2600 [bar]TMLP(P)≤T≤76.85 [◦C]
122.5≤P≤5.0401×106 [Pa]1.225×10−3 ≤P≤50.401 [bar]0≤X≤1.0 [–]103.986≤T≤282.3452 [K]−169.164≤T≤9.1952 [◦ C]
103.986≤T≤282.3452 [K]−169.164≤T≤9.1952 [◦ C]

VTX: Speciﬁc Volume of Mixture [m3 /kg]
T∗: Temperature [K], [◦ C]
X: Dryness Fraction [–]103.986≤T≤282.3452 [K]−169.164≤T≤9.1952 [◦ C]
0≤X≤1.0 [–]WPT: Velocity of Sound [m/s]P∗: Pressure [Pa], [bar]T∗: Temperature [K], [◦ C]

10000≤P≤40×106 [Pa]TMLP(P)≤T≤450 [K]
40×106 <P≤260×106 [Pa]TMLP(P)≤T≤350 [K]
0.1≤P≤400 [bar]TMLP(P)≤T≤176.85 [◦C]
400<P≤2600 [bar]TMLP(P)≤T≤76.85 [◦C]

8G
8H
56

WTD(T)WTDD(T)
XPH(P,H)57

XPS(P,S)58

XPU(P,U)59

XPV(P,V)

XPH: Dryness Fraction [–]P∗: Pressure [Pa], [bar]H: Speciﬁc Enthalpy of Mixture [J/kg]
XPS: Dryness Fraction [–]P∗: Pressure [Pa], [bar]S: Speciﬁc Entropy of Mixture [J/(kg·K)]
XPU: Dryness Fraction [–]P∗: Pressure [Pa], [bar]U: Speciﬁc Internal Energy of Mixture [J/kg]
XPV: Dryness Fraction [–]P∗: Pressure [Pa], [bar]V: Speciﬁc Volume of Mixture [m3 /kg]

122.5≤P<5.0401×106 [Pa]1.225×10−3 ≤P<50.401 [bar]HPD(P)≤H≤HPDD(P) [J/kg]
122.5≤P<5.0401×106 [Pa]1.225×10−3 ≤P<50.401 [bar]SPD(P)≤S≤SPDD(P) [J/(kg·K)]
122.5≤P<5.0401×106 [Pa]1.225×10−3 ≤P<50.401 [bar]UPD(P)≤U≤UPDD(P) [J/kg]
122.5≤P<5.0401×106 [Pa]1.225×10−3 ≤P<50.401 [bar]VPD(P)≤V≤VPDD(P) [m3 /kg]

Ethylene

253
Table II–2.25–1

No.
60

Name of
Function
XTH(T,H)

61

XTS(T,S)62

XTU(T,U)63

XTV(T,V)

Ethylene Function (cont’d)

Function and Argument(s)Range of Argument(s)XTH: Dryness Fraction [–]T∗: Temperature [K], [◦ C]
H: Speciﬁc Enthalpy of Mixture [J/kg]
XTS: Dryness Fraction [–]T∗: Temperature [K], [◦ C]
S: Speciﬁc Entropy of Mixture [J/(kg·K)]
XTU: Dryness Fraction [–]T∗: Temperature [K], [◦ C]
U: Speciﬁc Internal Energy of Mixture [J/kg]
XTV: Dryness Fraction [–]T∗: Temperature [K], [◦ C]
V: Speciﬁc Volume of Mixture [m3 /kg]

103.986≤T<282.3452 [K]−169.164≤T<9.1952 [◦ C]
HTD(T)≤H≤HTDD(T) [J/kg]
103.986≤T<282.3452 [K]−169.164≤T<9.1952 [◦ C]
STD(T)≤S≤STDD(T) [J/(kg·K)]
103.986≤T<282.3452 [K]−169.164≤T<9.1952 [◦ C]
UTD(T)≤U≤UTDD(T) [J/kg]
103.986≤T<282.3452 [K]−169.164≤T<9.1952 [◦ C]
VTD(T)≤V≤VTDD(T) [m3 /kg]