234

P-PROPATH: Pure Substances and Mixtures with Fixed Composition

2.24 Methane(Friend, Ely and Ingham)
Equations for thermodynamic properties have been cited from Friend et al. [1], surface tension from Miller et
al. [2], and pressure and temperature on melting line from the IUPAC [3].

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

2.24.2 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:

Methanelibjch42.a
JCH42.LIB
ch42-ss
CH42–SS.EXE

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

CH4
16.043518.264 J/(kg·K)

Critical Constants:
Critical Pressure:
Critical Temperature:
Critical Speciﬁc Volume:4.5992×10 6Pa (45.992 bar)190.551 K (−82.599 ◦C)
6.1478×10 −3m3 /kg

Triple Point:
Pressure:
Temperature:

0.011696×10 6Pa (0.11696 bar)90.6854 K (−182.4646 ◦C)

Reference State:
At 1.01325bar (1 atm) and 25 ◦ C(298.15 K), 186.266 J/(K.mol) is assigned to the speciﬁc entropy of the idealgas, and 10.0177 kJ/mol assigned to the speciﬁc enthalpy of the ideal gas.

2.24.4 Formula
Equation of State:
Equation (1) in a function form of A = A(ρ, T ) in reference [1]. Here A=molar Helmholtz energy, ρ=density
and T =Temperature.
Vapor Pressure:
Table 7 in reference [1].
Properties at Vapor-Liquid Equilibrium:
Equation (4) and equation (5) in reference [1] for saturation density of liquid and vapor respectively, equation(3) in reference [1] for pressure at saturation.
Pressure and Temperature on Melting Line:
Equation (52) in the reference [3].
Transport Properties:

Methane(Friend, Ely and Ingham)

235

Equation (8) and equation (9) in reference [1] for viscosity and thermal conductivity respectively.
The Other Properties:
Equation (23-1) in reference [2] for surface tension.

References[1] D.G.Friend, J.F.Ely, and H.Ingham, Thermal Properties of Methane, J. Phys. Chem. Ref. Data, Vol.18,
No.2, 1989, pp.583-638.
[2] J.W.Miller, Jr. and C.L.Yaws, Chem. Eng.,83-23, (1976), p.127.
[3] S.Angus and K.M.de Reuck, International Thermodynamic Table of the Fluid State-5 Methane, IUPAC,
vol.5, (1976).

236

P-PROPATH: Pure Substances and Mixtures with Fixed Composition
Table II–2.24–1

No.
1
94

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

Methane Function

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

Range of Argument(s)11.696×103 ≤P≤40×106 [Pa]TMLP(P)≤T≤600 [K]
40×106 <P≤109 [Pa]TMLP(P)≤T≤470 [K]
0.11696≤P≤400 [bar]TMLP(P)≤T≤326.85 [◦C]
400<P≤10000 [bar]TMLP(P)≤T≤196.85 [◦C]

8A
8B
82

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

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

11.696×103 ≤P≤40×106 [Pa]TMLP(P)≤T≤600 [K]
40×106 <P≤109 [Pa]TMLP(P)≤T≤470 [K]
0.11696≤P≤400 [bar]TMLP(P)≤T≤326.85 [◦C]
400<P≤10000 [bar]TMLP(P)≤T≤196.85 [◦C]

8C
8D
2
3
4

AKTD(T)
AKTDD(T)
ALAPP(P)
ALAPT(T)
ALHP(P)

5

ALHT(T)

6
7
8

ALMPD(P)ALMPDD(P)
ALMPT(P,T)

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

11.696×103 ≤P≤4.5992×106 [Pa]0.11696≤P≤45.992 [bar]90.6854≤T≤190.551 [K]−182.4646≤T≤−82.599 [◦ C]

ALMPT: Thermal Conductivity [W/(m·K)]
P∗: Pressure [Pa], [bar]T∗: Temperature [K], [◦C]

P≤70×106 [Pa]91≤T≤600 [K]P≤1000 [bar]-182.15≤T≤326.85 [◦ C]

9
10
11

ALMTD(T)ALMTDD(T)
AMUPD(P)12

AMUPDD(P)13

AMUPT(P,T)

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

PST(95K)≤P≤4.5992×106 [Pa]PST(−178.15◦ C)≤P≤45.992 [bar]PST(95K)≤P≤4.5992×106 [Pa]PST(−178.15◦ C)≤P≤45.992 [bar]P≤55times106
91≤T≤400 [K]P≤550 [bar]−182.25≤T≤136.85 [◦ C]

Methane(Friend, Ely and Ingham)

237

Table II–2.24–1

No.
14

Name of
Function
AMUTD(T)15

AMUTDD(T)92

BPPT(P,T)

90

91

93

BSPT(P,T)

BTPT(P,T)

BVPT(P,T)

16

CPPD(P)

17

CPPDD(P)18

CPPT(P,T)

Methane Function (cont’d)

Function and Argument(s)AMUTD: Coeﬃcient of Viscosity of
Saturated Liquid [Pa·s]
T∗: Temperature [K], [◦ C]
AMUTDD: Coeﬃcient of Viscosity of
Saturated Vapor [Pa·s]
T∗: Temperature [K], [◦ C]
BPPT: Volumetric Coeﬃcient of Expansion [1/K]
P∗: Pressure [Pa], [bar]T∗: Temperature [K], [◦ C]

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

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]

Range of Argument(s)95≤T≤190.551 [K]−178.15≤T≤−82.599 [◦ C]
95≤T≤190.551 [K]−178.15≤T≤−82.599 [◦ C]
11.696×103 ≤P≤40×106 [Pa]TMLP(P)≤T≤600 [K]
40×106 <P≤109 [Pa]TMLP(P)≤T≤470 [K]
0.11696≤P≤400 [bar]TMLP(P)≤T≤326.85 [◦C]
400<P≤10000 [bar]TMLP(P)≤T≤196.85 [◦C]
11.696×103 ≤P≤40×106 [Pa]TMLP(P)≤T≤600 [K]
40×106 <P≤109 [Pa]TMLP(P)≤T≤470 [K]
0.11696≤P≤400 [bar]TMLP(P)≤T≤326.85 [◦C]
400<P≤10000 [bar]TMLP(P)≤T≤196.85 [◦C]
11.696×103 ≤P≤40×106 [Pa]TMLP(P)≤T≤600 [K]
40×106 <P≤109 [Pa]TMLP(P)≤T≤470 [K]
0.11696≤P≤400 [bar]TMLP(P)≤T≤326.85 [◦C]
400<P≤10000 [bar]TMLP(P)≤T≤196.85 [◦C]
11.696×103 ≤P≤40×106 [Pa]TMLP(P)≤T≤600 [K]
40×106 <P≤109 [Pa]TMLP(P)≤T≤470 [K]
0.11696≤P≤400 [bar]TMLP(P)≤T≤326.85 [◦C]
400<P≤10000 [bar]TMLP(P)≤T≤196.85 [◦C]
11.696×103 ≤P≤4.5992×106 [Pa]0.11696≤P≤45.992 [bar]11.696×103 ≤P≤4.5992×106 [Pa]0.11696≤P≤45.992 [bar]11.696×103 ≤P≤40×106 [Pa]TMLP(P)≤T≤600 [K]
40×106 <P≤109 [Pa]TMLP(P)≤T≤470 [K]
0.11696≤P≤400 [bar]TMLP(P)≤T≤326.85 [◦C]
400<P≤10000 [bar]TMLP(P)≤T≤196.85 [◦C]

238

P-PROPATH: Pure Substances and Mixtures with Fixed Composition
Table II–2.24–1

No.
19

Name of
Function
CPTD(T)

20

CPTDD(T)21

CRP(‘A’)

7A
76

CVPD(P)
CVPDD(P)77

CVPT(P,T)

Methane Function (cont’d)

Function and Argument(s)Range of Argument(s)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’: 1.36097×105 [J/kg] Speciﬁc EnthalpyP∗: ‘A’=‘P’: 4.5992×106 [Pa], 45.992 [bar] Pressure
S: ‘A’=‘S’: 5.19385×103 [J/(kg·K)] Speciﬁc EntropyT∗: ‘A’=‘T’: 190.551 [K], −82.599 [◦C] Temperature
V: ‘A’=‘V’: 6.1478×10−3 [m3 /kg] Speciﬁc Volume

90.6854≤T≤190.551 [K]−182.4646≤T≤−82.599 [◦C]

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]

11.696×103 ≤P≤4.5992×106 [Pa]0.11696≤P≤45.992 [bar]90.6854≤T≤190.551 [K]−182.4646≤T≤−82.599 [◦C]
one of ‘H’, ‘P’, ‘S’, ‘T’ and ‘V’

11.696×103 ≤P≤40×106 [Pa]TMLP(P)≤T≤600 [K]
40×106 <P≤109 [Pa]TMLP(P)≤T≤470 [K]
0.11696≤P≤400 [bar]TMLP(P)≤T≤326.85 [◦ C]
400<P≤10000 [bar]TMLP(P)≤T≤196.85 [◦ 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]

90.6854≤T≤190.551 [K]−182.4646≤T≤−82.599 [◦C]

FC: Fundamental Constants
M: ‘A’=‘M’: 16.043 Relative Molecular Mass
R: ‘A’=‘R’: 518.25 [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]

11.696×103 ≤P≤4.5992×106 [Pa]0.11696≤P≤45.992 [bar]11.696×103 ≤P≤40×106 [Pa]TMLP(P)≤T≤600 [K]
40×106 <P≤109 [Pa]TMLP(P)≤T≤470 [K]
0.11696≤P≤400 [bar]TMLP(P)≤T≤326.85 [◦ C]
400<P≤10000 [bar]TMLP(P)≤T≤196.85 [◦ C]

9B
97

GAMTD(T)GAMTDD(T)23

HPD(P)

24

HPDD(P)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]90.6854≤T≤190.551 [K]−182.4646≤T≤−82.599 [◦C]
11.696×103 ≤P≤4.5992×106 [Pa]0.11696≤P≤45.992 [bar]11.696×103 ≤P≤4.5992×106 [Pa]0.11696≤P≤45.992 [bar]Methane(Friend, Ely and Ingham)

239

Table II–2.24–1

No.
71

25

Name of
Function
HPS(P,S)

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

PRPD(P)PRPDD(P)
PRPT(P,T)

Methane Function (cont’d)

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

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’: ‘CH4’ Molecular Formula
S: ‘A’=‘S’: ‘METHANE’ Name of Substance
V: ‘A’=‘V’: ‘11.1’ Version Number

Range of Argument(s)11.696×103 ≤P≤40×106 [Pa]SPT(P,TMLP(P))≤S≤
SPT(P,600K) [J/(kg·K)]
40×106 <P≤109 [Pa]SPT(P,TMLP(P))≤S≤
SPT(P,470K) [J/(kg·K)]
0.11696≤P≤400 [bar]SPT(P,TMLP(P))≤S≤
SPT(P,326.85◦ C) [J/(kg·K)]
400<P≤10000 [bar]SPT(P,TMLP(P))≤S≤
SPT(P,196.85◦ C) [J/(kg·K)]
11.696×103 ≤P≤40×106 [Pa]TMLP(P)≤T≤600 [K]
40×106 <P≤109 [Pa]TMLP(P)≤T≤470 [K]
0.11696≤P≤400 [bar]TMLP(P)≤T≤326.85 [◦C]
400<P≤10000 [bar]TMLP(P)≤T≤196.85 [◦C]
11.696×103 ≤P≤4.5992×106 [Pa]0.11696≤P≤45.992 [bar]0≤X≤1.0 [–]90.6854≤T≤190.551 [K]−182.4646≤T≤−82.599 [◦ C]
90.6854≤T≤190.551 [K]−182.4646≤T≤−82.599 [◦ C]
90.6854≤T≤190.551 [K]−182.4646≤T≤−82.599 [◦ C]
0≤X≤1.0 [–]one of ‘C’, ‘S’ and ‘V’

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

90.6854≤T≤260 [K]−182.4646≤T≤−13.15 [◦ C]

PRPT: Prandtl Number [–]P∗: Pressure [Pa], [bar]T∗: Temperature [K], [◦ C]

100×103 ≤P≤50×106 [Pa]300≤T≤423.15 [K]
1.0≤P≤500 [bar]26.85≤T≤150 [◦ C]

87
88
99
30

PRTD(T)
PRTDD(T)PSBT(T)
PST(T)72
73
31

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

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

90.6854≤T≤190.551 [K]−182.4646≤T≤−82.599 [◦ C]

SIGP: Surface Tension [N/m]P∗: Pressure [Pa], [bar]11.696×103 ≤P≤4.5992×106 [Pa]0.11696≤P≤45.992 [bar]240P-PROPATH: Pure Substances and Mixtures with Fixed Composition
Table II–2.24–1

No.
32

Name of
Function
SIGT(T)

33

SPD(P)34

SPDD(P)35

SPT(P,T)36

SPX(P,X)

37

STD(T)38

STDD(T)

39

STX(T,X)

67
69

TLDP(P)
TMLP(P)64

TPH(P,H)

Methane Function (cont’d)

Function and Argument(s)Range of Argument(s)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]

90.6854≤T≤190.551 [K]−182.4646≤T≤−82.599 [◦C]
11.696×103 ≤P≤4.5992×106 [Pa]0.11696≤P≤45.992 [bar]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 [–]TMLP∗: Temperature on Melting Curve[K], [◦ C]
P∗: Pressure [Pa], [ bar]
TPH∗: Temperature [K], [◦C]P∗: Pressure [Pa], [bar]H: Speciﬁc Enthalpy [J/kg]

11.696×103 ≤P≤4.5992×106 [Pa]0.11696≤P≤45.992 [bar]11.696×103 ≤P≤40×106 [Pa]TMLP(P)≤T≤600 [K]
40×106 <P≤109 [Pa]TMLP(P)≤T≤470 [K]
0.11696≤P≤400 [bar]TMLP(P)≤T≤326.85 [◦ C]
400<P≤10000 [bar]TMLP(P)≤T≤196.85 [◦ C]
11.696×103 ≤P≤4.5992×106 [Pa]0.11696≤P≤45.992 [bar]0≤X≤1.0 [–]90.6854≤T≤190.551 [K]−182.4646≤T≤−82.599 [◦C]
90.6854≤T≤190.551 [K]−182.4646≤T≤−82.599 [◦C]
90.6854≤T≤190.551 [K]−182.4646≤T≤−82.599 [◦C]
0≤X≤1.0 [–]11.696×103 ≤P≤109 [Pa]0.11696≤P≤10000 [bar]11.696×103 ≤P≤40×106 [Pa]
HPT(P,TMLP(P))≤H≤
HPT(P,600K) [J/kg]
40×106 <P≤109 [Pa]
HPT(P,TMLP(P))≤H≤
HPT(P,470K) [J/kg]
0.11696≤P≤400 [bar]HPT(P,TMLP(P))≤H≤
HPT(P,326.85◦ C) [J/kg]
400<P≤10000 [bar]HPT(P,TMLP(P))≤H≤
HPT(P,196.85◦ C) [J/kg]

6H

TPH2(P,H)

Methane(Friend, Ely and Ingham)

241

Table II–2.24–1

No.
65

Name of
Function
TPS(P,S)

Methane Function (cont’d)

Function and Argument(s)TPS∗: Temperature [K], [◦ C]
P∗: Pressure [Pa], [bar]S: Speciﬁc Entropy [J/(kg·K)]

Range of Argument(s)11.696×103 ≤P≤40×106 [Pa]SPT(P,TMLP(P))≤S≤
SPT(P,600K) [J/(kg·K)]
40×106 <P≤109 [Pa]SPT(P,TMLP(P))≤S≤
SPT(P,470K) [J/(kg·K)]
0.11696≤P≤400 [bar]SPT(P,TMLP(P))≤S≤
SPT(P,326.85◦ C) [J/(kg·K)]
400<P≤10000 [bar]SPT(P,TMLP(P))≤S≤
SPT(P,196.85◦ C) [J/(kg·K)]

6S
98

TPS2(P,S)TPSEUP(P)70

TPV(P,V)41

TRPL(‘A’)

100
40

TSBP(P)
TSP(P)

74
75
42

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

UPDD(P)

7944

UPS(P,S)
UPT(P,T)45

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

TRPL∗: Properties at Triple PointP∗: ‘A’=‘P’: 11.696×103 [Pa],0.11696 [bar] PressureT∗: ‘A’=‘T’: 90.6854 [K],−182.4646 [◦ C] Temperature

4.5992×106 <P≤50×106 [Pa]45.992<P≤500 [bar]11.696×103 ≤P≤40×106 [Pa]VPT(P,TMLP(P))≤V≤
VPT(P,600K) [m3 /kg]
40×106 <P≤109 [Pa]VPT(P,TMLP(P))≤V≤
VPT(P,470K) [m3 /kg]
0.11696≤P≤400 [bar]VPT(P,TMLP(P))≤V≤
VPT(P,326.85◦C) [m3 /kg]
400<P≤10000 [bar]VPT(P,TMLP(P))≤V≤
VPT(P,196.85◦C) [m3 /kg]
one of ‘P’ and ‘T’

TSP∗: Saturation Temperature [K], [◦C]P∗: Pressure [Pa], [bar]11.696×103 ≤P≤4.5992×106 [Pa]0.11696≤P≤45.992 [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]11.696×103 ≤P≤4.5992×106 [Pa]0.11696≤P≤45.992 [bar]

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

11.696×103 ≤P≤40×106 [Pa]TMLP(P)≤T≤600 [K]
40×106 <P≤109 [Pa]TMLP(P)≤T≤470 [K]

UPX: Speciﬁc Internal Energy of Mixture [J/kg]
P∗: Pressure [Pa], [bar]
X: Dryness Fraction [–]11.696×103 ≤P≤4.5992×106 [Pa]0.11696≤P≤45.992 [bar]0.11696≤P≤400 [bar]TMLP(P)≤T≤326.85 [◦ C]
400<P≤10000 [bar]TMLP(P)≤T≤196.85 [◦ C]
11.696×103 ≤P≤4.5992×106 [Pa]0.11696≤P≤45.992 [bar]0≤X≤1.0 [–]242

P-PROPATH: Pure Substances and Mixtures with Fixed Composition
Table II–2.24–1

No.
46

Name of
Function
UTD(T)

47

UTDD(T)

48

UTX(T,X)

49

VPD(P)50

VPDD(P)

80
51

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)

Methane Function (cont’d)

Function and Argument(s)Range of Argument(s)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]90.6854≤T≤190.551 [K]−182.4646≤T≤−82.599 [◦ C]

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

11.696×103 ≤P≤40×106 [Pa]TMLP(P)≤T≤600 [K]
40×106 <P≤109 [Pa]TMLP(P)≤T≤470 [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]
VTX: Speciﬁc Volume of Mixture [m3 /kg]
T∗: Temperature [K], [◦ C]
X: Dryness Fraction [–]WPT: Velocity of Sound [m/s]P∗: Pressure [Pa], [bar]T∗: Temperature [K], [◦ C]

90.6854≤T≤190.551 [K]−182.4646≤T≤−82.599 [◦ C]
90.6854≤T≤190.551 [K]−182.4646≤T≤−82.599 [◦ C]
0≤X≤1.0 [–]11.696×103 ≤P≤4.5992×106 [Pa]0.11696≤P≤45.992 [bar]11.696×103 ≤P≤4.5992×106 [Pa]0.11696≤P≤45.992 [bar]0.11696≤P≤400 [bar]TMLP(P)≤T≤326.85 [◦C]
400<P≤10000 [bar]TMLP(P)≤T≤196.85 [◦C]
11.696×103 ≤P≤4.5992×106 [Pa]0.11696≤P≤45.992 [bar]0≤X≤1.0 [–]90.6854≤T≤190.551 [K]−182.4646≤T≤−82.599 [◦ C]
90.6854≤T≤190.551 [K]−182.4646≤T≤−82.599 [◦ C]
90.6854≤T≤190.551 [K]−182.4646≤T≤−82.599 [◦ C]
0≤X≤1.0 [–]11.696×103 ≤P≤40×106 [Pa]TMLP(P)≤T≤600 [K]
40×106 <P≤109 [Pa]TMLP(P)≤T≤470 [K]
0.11696≤P≤400 [bar]TMLP(P)≤T≤326.85 [◦C]
400<P≤10000 [bar]TMLP(P)≤T≤196.85 [◦C]

8G
8H
56

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

XPS(P,S)

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)]

11.696×103 ≤P≤4.5992×106 [Pa]0.11696≤P≤45.992 [bar]HPD(P)≤H≤HPDD(P) [J/kg]
11.696×103 ≤P≤4.5992×106 [Pa]0.11696≤P≤45.992 [bar]SPD(P)≤S≤SPDD(P) [J/(kg·K)]

Methane(Friend, Ely and Ingham)

243

Table II–2.24–1

No.
58

Name of
Function
XPU(P,U)59

XPV(P,V)60

XTH(T,H)

61

XTS(T,S)62

XTU(T,U)63

XTV(T,V)

Methane Function (cont’d)

Function and Argument(s)Range of Argument(s)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]
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]

11.696×103 ≤P≤4.5992×106 [Pa]0.11696≤P≤45.992 [bar]UPD(P)≤U≤UPDD(P) [J/kg]
11.696×103 ≤P≤4.5992×106 [Pa]0.11696≤P≤45.992 [bar]VPD(P)≤V≤VPDD(P) [m3 /kg]
90.6854≤T≤190.551 [K]−182.4646≤T≤−82.599 [◦ C]
HTD(T)≤H≤HTDD(T) [J/kg]
90.6854≤T≤190.551 [K]−182.4646≤T≤−82.599 [◦ C]
STD(T)≤S≤STDD(T) [J/(kg·K)]
90.6854≤T≤190.551 [K]−182.4646≤T≤−82.599 [◦ C]
UTD(T)≤U≤UTDD(T) [J/kg]
90.6854≤T≤190.551 [K]−182.4646≤T≤−82.599 [◦ C]
VTD(T)≤V≤VTDD(T) [m3 /kg]