Air123

2.12 Air
Equations for the thermodynamic properties have been cited from Baehr et al.[1], and those for transport properties from Kadoya et al.[2].

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

2.12.2 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:

Air
libjair.a
JAIR.LIB
air-ss
AIR–SS.EXE

2.12.3 Important Constants and Others
Molecular Formula:

Molecular Weight:
Gas Constant:

Air mixture
N2 = 0.7841 (kmol N2 /kmol Air)O2 = 0.2066 (kmol O2 /kmol Air)
Ar= 0.0093 (kmol Ar/kmol Air)
28.96
287.22 J/(kg·K)

Critical Constants (Maximum Temperature):

Critical Constants (Minimum Pressure):

Critical Pressure:
Critical Temperature:
Critical Speciﬁc Volume:

Critical Pressure:
Critical Temperature:
Critical Speciﬁc Volume:3.76625×10 6Pa (37.6625 bar)132.52K(−140.63 ◦C)
3.19489×10 −3m3 /kg

3.77431×10 6Pa (37.7431 bar)132.42K(−140.73 ◦C)
2.96020×10 −3m3 /kg

Reference State:
At 1.01325 bar (1 atm) and −233.15 ◦C(40 K)(ideal gas), 4845.72J/(kg·K) is assigned to the speciﬁc entropy.
At −233.15 ◦C(40 K)(ideal gas), 28325.0 J/kg is assigned to the speciﬁc internal energy.

2.12.4 Formula
Equation of State:
Equations (28) and (43b) in a function form of P = P (ρ, T ) in reference [1]. Here P =pressure, ρ=density and
T =temperature.
Pressure and Temperature on Dew-Point Curve (Saturated Vapor):Equation (36) in reference [1].
Pressure and Temperature on Bubble-Point Curve (Saturated Liquid):
Equation (37) in reference [1].
Properties at Vapor-Liquid Equilibrium:saturated liquid; Equations (38a), (54) and (56) for speciﬁc volume, speciﬁc entropy, and speciﬁc enthalpy,
respectively.
saturated vapor; Equations (36) and (43b) for speciﬁc volume, (36) and (46) for speciﬁc entropy, (36) and (45)for speciﬁc enthalpy, (36) and (48) for isochoric speciﬁc heat, and (36) and (49) for isobaric speciﬁc heat.

124

P-PROPATH: Pure Substances and Mixtures with Fixed Composition

All of these equations have been cited from reference [1].
Transport Properties:
Viscosity and thermal conductivity from reference[2].

References[1] H.D.Baehr and K.Schwier, Die thermodynamischen Eigenschaften der Luft, Springer-Verlag, (1961).
[2] K.Kadoya, N.Matsunaga and A.Nagashima, Viscosity and Thermal Conductivity of Dry Air in the Gaseous
Phase, Journal of Physical and Chemical Reference Data, vol.14, No.4, (1985), p.947.

Air

125
Table II–2.12–1 Air Function

No.
1
94
8A
8B
82

Name of
Function
AIPPT(P,T)
AJTPT(P,T)
AKPD(P)AKPDD(P)AKPT(P,T)

Function and Argument(s)AKPT: Isentropic Exponent [–]P∗: Pressure [Pa], [bar]T∗: Temperature [K], [◦ C]

Range of Argument(s)0≤P≤450×106 [Pa]60≤T≤1523.15 [K]0≤P≤4500 [bar]−213.15≤T≤1250 [◦C]
see Fig.II-2-3

8C
8D
2
3
4

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

56
78

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

ALHP: Latent Heat of Vaporization [J/kg]
P∗: Pressure [Pa], [bar]40×103 ≤P≤3.6×106 [Pa]0.4≤P≤36 [bar]

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

0≤P≤100×106 [Pa]85≤T≤2000 [K]0≤P≤1000 [bar]−188.15≤T≤1726.85 [◦C]
see Fig.II-2-1

9
10
11
12
13

ALMTD(T)ALMTDD(T)
AMUPD(P)AMUPDD(P)AMUPT(P,T)

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

0≤P≤100×106 [Pa]85≤T≤2000 [K]0≤P≤1000 [bar]−188.15≤T≤1726.85 [◦C]
see Fig.II-2-2

14
15
92
90
91
93
16
17

AMUTD(T)AMUTDD(T)BPPT(P,T)
BSPT(P,T)
BTPT(P,T)
BVPT(P,T)
CPPD(P)CPPDD(P)18

CPPT(P,T)

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]

1000≤P≤3.76625×106 [Pa]0.01≤P≤37.6625 [bar]0≤P≤450×106 [Pa]60≤T≤1523.15 [K]0≤P≤4500 [bar]−213.15≤T≤1250 [◦C]
see Fig.II-2-3

19
20

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

60≤T≤132.52 [K]−213.15≤T≤−140.63 [◦ C]

126

P-PROPATH: Pure Substances and Mixtures with Fixed Composition
Table II–2.12–1 Air Function (cont’d)

No.
21

Name of
Function
CRP(‘A’)

7A
76

CVPD(P)
CVPDD(P)77

CVPT(P,T)

Function and Argument(s)Range of Argument(s)CRP: Critical Constants
H: ‘A’=‘H’: 34.248×103 [J/kg] Speciﬁc EnthalpyP∗: ‘A’=‘P’: 3.76625×106 [Pa],37.6625 [bar]Pressure
S: ‘A’=‘S’: 4.3843×103 [J/(kg·K)] Speciﬁc EntropyT∗: ‘A’=‘T’: 132.52 [K],−140.63 [◦ C]
Temperature
V: ‘A’=‘V’: 3.19489×10−3 [m3 /kg] Speciﬁc Volume

one of ‘H’, ‘P’, ‘S’, ‘T’ and ‘V’

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]

1000≤P≤3.76625×106 [Pa]0.01≤P≤37.6625 [bar]0≤P≤450×106 [Pa]60≤T≤1523.15 [K]0≤P≤4500 [bar]−213.15≤T≤1250 [◦ C]
see Fig.II-2-3

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
95
9B
97
23

GAMPD(P)GAMPDD(P)GAMPT(P,T)
GAMTD(T)GAMTDD(T)HPD(P)

24

HPDD(P)71

HPS(P,S)

25

HPT(P,T)

26

HPX(P,X)

27

HTD(T)28

HTDD(T)

29

HTX(T,X)

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

60≤T≤132.52 [K]−213.15≤T≤−140.63 [◦C]

FC: Fundamental Constants
M: ‘A’=‘M’: 28.96 Relative Molecular Mass
R: ‘A’=‘R’: 287.22 [J/(kg·K)] Gas Constant

one of ‘M’ and ‘R’

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

40×103 ≤P≤3.6×106 [Pa]0.4≤P≤36 [bar]1000≤P≤3.76625×106 [Pa]0.01≤P≤37.6625 [bar]1000≤P≤450×106 [Pa]0.01≤P≤4500 [bar]see Fig.II-2-5 for S
1000≤P≤450×106 [Pa]60≤T≤1523.15 [K]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]

0.01≤P≤4500 [bar]−213.15≤T≤1250 [◦ C]
see Fig.II-2-3
40×103 ≤P≤3.6×106 [Pa]0.4≤P≤36 [bar]0≤X≤1.0 [–]68≤T≤132 [K]−205.15≤T≤−141.15 [◦C]
60≤T≤132.52 [K]−213.15≤T≤−140.63 [◦C]

Air

127
Table II–2.12–1 Air Function (cont’d)No.
84

Name of
Function
IDENTF(‘A’)

66
68
85
86
81

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

Function and Argument(s)Range of Argument(s)IDENTF : CHARACTER TYPE FUNCTION
for Package Identiﬁcation (Length 20)
C: ‘A’=‘C’: ‘AIR’ Molecular Formula
S: ‘A’=‘S’: ‘AIR’ Name of Substance
V: ‘A’=‘V’: ‘10.1’ Version Number

one of ‘C’, ‘S’ and ‘V’

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

0≤P≤0.1473×106 [Pa]85≤T≤1523.15 [K]
0.1473×106 <P≤3.3×106 [Pa]TSPDD(P)≤T≤1523.15 [K]
3.3×106 <P≤42.791×106 [Pa]159≤T≤1523.15 [K]42.791×106 <P≤92.72×106 [Pa]TPV(P,1.42×10−3 m3 /kg)
≤T≤1523.15 [K]92.72×106 <P≤100×106 [Pa]223.15≤T≤1523.15 [K]0≤P≤1.473 [bar]−188.15≤T≤1250 [◦ C]
1.473<P<33 [bar]TSPDD(P)≤T≤1250 [◦ C]
33<P≤427.91 [bar]−78.15≤T≤1250 [◦ C]
427.91<P≤927.2 [bar]
TPV(P,1.42×10−3 m3 /kg)
≤T≤1250 [◦ C]
927.2<P≤1000 [bar]−40≤T≤1250 [◦C]

87
88
99
30
72

PRTD(T)
PRTDD(T)PSBT(T)
PST(T)PSTD(T)73

PSTDD(T)31
32
33

SIGP(P)
SIGT(T)
SPD(P)34

SPDD(P)35

SPT(P,T)

PSTD∗: Pressure [Pa], [bar] on Bubble-Point
Curve (Saturated Liquid)T∗: Temperature [K], [◦ C]
PSTDD∗: Pressure [Pa], [bar] on Dew-Point
Curve (Saturated Vapor)
T∗: Temperature [K], [◦ C]

68≤T≤132.42 [K]−205.15≤T≤−140.73 [◦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]

40×103 ≤P≤3.6×106 [Pa]0.4≤P≤36 [bar]60≤T≤132.52 [K]−213.15≤T≤−140.63 [◦C]

1000≤P≤3.76625×106 [Pa]0.01≤P≤37.6625 [bar]1000≤P≤450×106 [Pa]60≤T≤1523.15 [K]0.01≤P≤4500 [bar]−213.15≤T≤1250 [◦ C]
see Fig.II-2-3

128

P-PROPATH: Pure Substances and Mixtures with Fixed Composition
Table II–2.12–1 Air Function (cont’d)No.
36

Name of
Function
SPX(P,X)

37

STD(T)38

STDD(T)

39
67
69
64

STX(T,X)
TLDP(P)
TMLP(P)
TPH(P,H)

6H
65

TPH2(P,H)
TPS(P,S)

6S
98
70

TPS2(P,S)TPSEUP(P)TPV(P,V)

41
100
40
74

TRPL(‘A’)
TSBP(P)
TSP(P)
TSPD(P)75

TSPDD(P)42

UPD(P)43

UPDD(P)79

UPS(P,S)

44

UPT(P,T)45

UPX(P,X)

46

UTD(T)

47

UTDD(T)

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]

40×103 ≤P≤3.6×106 [Pa]0.4≤P≤36 [bar]0≤X≤1.0 [–]68≤T≤132 [K]−205.15≤T≤−141.15 [◦ C]

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

1000≤P≤450×106 [Pa]0.01≤P≤4500 [bar]see Fig.II-2-4 for H

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

1000≤P≤450×106 [Pa]0.01≤P≤4500 [bar]see Fig.II-2-5 for S

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

1000≤P≤450×106 [Pa]0.01≤P≤4500 [bar]see Fig.II-2-6 for V

TSPD∗: Temperature [K], [◦ C] on Bubble-Point
Curve (Saturated Liquid)P∗: Pressure [Pa], [bar]TSPDD∗: Temperature [K], [◦ C] on Dew-Point
Curve (Saturated Vapor)P∗: Pressure [Pa], [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)]
UPT: Speciﬁc Internal Energy [J/kg]
P∗: Pressure [Pa], [bar]T∗: Temperature [K], [◦ C]

40×103 ≤P≤3.77434×106 [Pa]0.4≤P≤37.7434 [bar]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]

60≤T≤132.52 [K]−213.15≤T≤−140.63 [◦ C]

1000≤P≤3.76625×106 [Pa]0.01≤P≤37.6625 [bar]40×103 ≤P≤3.6×106 [Pa]0.4≤P≤36 [bar]1000≤P≤3.76625×106 [Pa]0.01≤P≤37.6625 [bar]1000≤P≤450×106 [Pa]0.01≤P≤4500 [bar]see Fig.II-2-5 for S
1000≤P≤450×106 [Pa]60≤T≤1523.15 [K]0.01≤P≤4500 [bar]−213.15≤T≤1250 [◦ C]
see Fig.II-2-3
40×103 ≤P≤3.6×106 [Pa]0.4≤P≤36 [bar]0≤X≤1.0 [–]68≤T≤132 [K]−205.15≤T≤−141.15 [◦ C]
60≤T≤132.52 [K]−213.15≤T≤−140.63 [◦ C]

Air

129
Table II–2.12–1 Air Function (cont’d)

No.
48
49

Name of
Function
UTX(T,X)
VPD(P)50

VPDD(P)80

VPS(P,S)

51

VPT(P,T)52

VPX(P,X)

53

VTD(T)54

VTDD(T)

55
8E
8F
83

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

Function and Argument(s)VPD: Speciﬁc Volume of Saturated Liquid [m3 /kg]P∗: Pressure [Pa], [bar]VPDD: Speciﬁc Volume of Saturated Vapor [m3 /kg]P∗: Pressure [Pa], [bar]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]

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]

WPT: Velocity of Sound [m/s]P∗: Pressure [Pa], [bar]T∗: Temperature [K], [◦ C]

Range of Argument(s)40×103 ≤P≤3.6×106 [Pa]0.4≤P≤36 [bar]1000≤P≤3.76625×106 [Pa]0.01≤P≤37.6625 [bar]1000≤P≤450×106 [Pa]0.01≤P≤4500 [bar]see Fig.II-2-5 for S
1000≤P≤450×106 [Pa]60≤T≤1523.15 [K]0.01≤P≤4500 [bar]−213.15≤T≤1250 [◦ C]
see Fig.II-2-3
40×103 ≤P≤3.6×106 [Pa]0.4≤P≤36 [bar]0≤X≤1.0 [–]68≤T≤132.52 [K]−205.15≤T≤−140.63 [◦C]
60≤T≤132.52 [K]−213.15≤T≤−140.63 [◦C]

0≤P≤450×106 [Pa]60≤T≤1523.15 [K]0≤P≤4500 [bar]−213.15≤T≤1250 [◦ C]
see Fig.II-2-3

8G
8H
56

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

XPS(P,S)58

XPU(P,U)59

XPV(P,V)

60
61
62
63

XTH(T,H)
XTS(T,S)XTU(T,U)XTV(T,V)

XPH: Dryness Fraction [–]P∗: Pressure [Pa], [bar]H: Speciﬁc Enthalpy of Mixture [J/(kg·K)]
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]

40×103 ≤P≤3.6×106 [Pa]0.4≤P≤36 [bar]HPD(P)≤H≤HPDD(P) [J/kg]
40×103 ≤P≤3.6×106 [Pa]0.4≤P≤36 [bar]SPD(P)≤S≤SPDD(P) [J/(kg·K)]
40×103 ≤P≤3.6×106 [Pa]0.4≤P≤36 [bar]UPD(P)≤U≤UPDD(P) [J/kg]
40×103 ≤P≤3.6×106 [Pa]0.4≤P≤36 [bar]VPD(P)≤V≤VPDD(P) [m3/kg]

130

P-PROPATH: Pure Substances and Mixtures with Fixed Composition[bar]*10 6 [Pa]
1000

100

Air
6

10
9.838

33.0

3.3

1.473
0

0.14730

D ew( S at - po i nt c u
u ra ter
d va vep or )

T = 159 K

Pressure, P

100
93.38

P = (0.00430T 2-1.03T + 64.9)*10
P:[Pa], T:[K]85-188.15200-73.15273.1501000
726.85Temperature, T
Fig.II–2.12–1 Range of Arguments(P,T) for ALMPT(P,T).

2000 [K]1726.85 [C]

Air

131

[bar]*10 6 [Pa]
1000

100

Air
100

10

6

Pressure, PP = (0.00430T 2-1.03T + 64.9)*10
P:[Pa], T:[K]

3.917
3.77

1.473
0

0.14730

T = 132.5 K
D ew( S at - po i nt c u
u ra ter
d va vep or )

39.17
37.7

85
-188.15200-73.15273.1501000
726.85Temperature, T
Fig.II–2.12–2

Range of Arguments(P,T) for AMUPT(P,T).

2000 [K]1726.85 [C]132

P-PROPATH: Pure Substances and Mixtures with Fixed Composition

204.0
477.15[bar]*10 6 [Pa]
4500

436.0
709.15576.0
849.156

450

4000

400

3500

350

[C]
[K]
-13 2

T = -0.2*10 P-6+19.8*10 P-4011
P:[Pa], T:[K]

Air
-13

2

-6

T = -0.665*10 P +54.5*10 P-10451
P:[MPa], T:[K]

1691

169.1

T = 223.15 K
927.2

92.72

206.1
50.0

20.61
5.0

V = 1.420*10+3 m3/kg
T = 132.52 K
Critical point

0.4
0

0.04
0

D ew -p o in t c
u rv e(S a tu ra te d v
ap o r)Pressure, P

V = 1.204*10 -3m3/kg

60-213.15500
226.851000
726.851523.15 [K]1250 [C]Temperature, T
Fig.II–2.12–3

Range of Arguments(P,T) for AKPT(P,T),CPPT(P,T),CVPT(P,T),HPT(P,T),
SPT(P,T),UPT(P,T),VPT(P,T) and WPT(P,T).

Air

133

[bar]*10 6 [Pa]
4500

450

4000

400

3500

350

-13 2

T = -0.2*10 P+19.8*10-6P-4011
P:[Pa], T:[K]

Air
-13

2

-6

T = -0.665*10 P +54.5*10 P-10451
P:[MPa], T:[K]

927.2

92.72

206.1
50.0

20.61
5.0

15 K
523.

169.1

T=1

1691

T = 223.15 K
V = 1.420*10+3 m3/kg
T = 132.52 K

0.4
0

0.04
0

Critical point-0.3 0

Sa tur ate d va po r

3.6
d liquid

36.0

Satur ate

Pressure, P

V = 1.204*10 -3m3/kg

0.5

1

1.5

Enthalpy, H [J/kg]
Fig.II–2.12–4 Range of Arguments(P,H) for TPH(P,H).

2.07 *10 6

134

P-PROPATH: Pure Substances and Mixtures with Fixed Composition[bar]*10 6 [Pa]
4500

450

4000

400

3500

350

-13 2

T = -0.2*10 P+19.8*10-6P-4011
P:[Pa], T:[K]

Air

-13

T = 223.15 K
927.2

92.72

206.1
50.0

20.61
5.0

5K

523.1

169.1

T=1

1691

V = 1.420*10+3 m3/kg
T = 132.52 K
Critical point

3.6

0.4
0

0.04
0

tu

ra

ted
2.9

v ap ot ed
a t u ra

liq

ui

d

r

36.0

S

Sa

Pressure, P

V = 1.204*10 -3m3/kg

2

T = -0.665*10 P+54.5*10-6P-10451
P:[MPa], T:[K]

4

5

6

7

8

Entropy, S [J/(kg.K)]
Fig.II–2.12–5

Range of Arguments(P,S) for HPS(P,S),TPS(P,S),UPS(P,S)
and VPS(P,S).

8.8

*10 3

Air

135

[bar]*10 6 [Pa]
4500

450

4000

400

3500

350

-13 2

-6

T = -0.2*10 P +19.8*10 P-4011
P:[Pa], T:[K]

Air

-13

2

-6

T = -0.665*10 P +54.5*10 P-10451
P:[MPa], T:[K]

1691

169.1

927.2

92.72

206.1
50.0

20.61
5.0

T = 223.15 K

V = 1.420*10+3 m3/kg

T = 1 5 2 3 .1

5K

T = 132.52 K
Critical point

3.6

Sa tur ated liq

uid

36.0

0.4
0

0.04
0

ted vap or

SaturaPressure, P

V = 1.204*10 -3m3/kg

2.90.00117

0.005

0.01

Specific Volume, V [m3/kg]
Fig.II–2–6

Range of Arguments(P,V) for TPV(P,V).

0.015