Thermo Scientific Sarasota SG901, User Manual

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Equations
E-4
Sarasota SG901 User Guide Thermo Fisher Scientific
Compressibility (Gas)
If B
z
x
ρ
m
> 1, then Z = 1.
Z = gas compressibility
A
z
= R-K fluid constant for Z in K
1.5
.m
3
/kg (°R
1.5
.ft
3
/lb)
B
z
= R-K fluid constant for Z in m
3
/kg (ft
3
/lb)
ρ
m
= measured density of gas
T = absolute temperature in K (°R)
Reference Compressibility (Gas)
On first pass through calculations, Zref = 1.
Subsequently,
If Zref < 0.8, then set Zref = 0.8.
If Zref > 1.145, then set Zref = 1.145.
Zref = reference compressibility
G = relative density (SG)
A
z
= R-K fluid constant for Z in K
1.5
.m
3
/kg (°R
1.5
.ft
3
/lb)
B
z
= R-K fluid constant for Z in m
3
/kg (ft
3
/lb)
Tref = reference temperature K (°R)
Gravity / Relative Density (Gas)
G = relative density (SG)
ρ
c
= density of gas at reference pressure and temperature
p
air
= density or air at reference pressure and temperature
( )
m z
5 . 1
m z
m z
B 1 T
A
B 1
1
Z
ρ × + ×
ρ ×
−
ρ × −
=






− × ρ × − =
z
1.5
z
air
B
Tref
A
G 1 Zref
ρ
ρ
=
air
c
G