Here you can calculate the valve flow coefficient for compressible fluids as defined in ISA-S75.01-1985 (R 1995). A gas mixture can be specified using the input-selectors together with the volumes ratio. For details of the calculations, approximations and valve test procedures see left (links).
The Kv is calculated using the following units: P[bar] Flow[sm3/h] Temp[K].
The Cv is calculated using the following units: P[psi]
Flow[scfh] Temp[R].
nL/h = norm Litres/hour. (Litres pr hour at Normal conditions)
Normal conditions: P=1013.25mb and T=273.15K
Standard conditions: P=1013.25mb and T=288.75K.
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