Correction for Upstream Density

Isenthalpic and Isentropic methods for correcting the downstream/recovery point density to upstream density

This standard calculates the upstream density from the downstream or recovery point density



For option: Upstream Density Calculation Method - Isentropic Exponent
The isentropic method as shown below is used to calculate the upstream density.

ISO_5167_Density_Isentropic

When 'Downstream' is selected differential pressure(Δp) is used. When 'Recovery Point' is selected permanent pressure loss(Δω) is used.



Symbol Description Units
ρ1 Upstream density kg/m3
ρ Downstream/recovery point density kg/m3
P1 Upstream pressure bar a
Δω Permanent pressure loss bar a
Δp Differential pressure bar a
k Isentropic exponent -


For option: Upstream Density Calculation Method - Isenthalpic
The isenthalpic method as shown below is used to calculate the upstream density.

ISO_5167_Density_Isenthalpic

When 'Downstream' is selected differential pressure(Δp) is used. When 'Recovery Point' is selected permanent pressure loss(Δω) is used.



Symbol Description Units
ρ1 Upstream density kg/m3
ρ Downstream/recovery point density kg/m3
P1 Upstream pressure bar a
T Temperature at the point of measured density Kelvin
T1 Upstream Temperature Kelvin
Z Compressibility at the point of measured density -
Z1 Upstream compressibility -
Δω Permanent pressure loss bar a
Δp Differential pressure bar a