Calculate typical gas and liquid pipe check valve minimum velocity and minor loss factors (K, Cd, Cv*, Av, Cv-uk, Cv-us, Cv-met and Kv).
The minimum flowrate is the flowrate required to keep the check valve fully open. For full port valves the valve port cross section area equals the nominal internal cross section area. For reduced port valves the valve port cross section area is less than the nominal internal cross section area. For circular valve ports the diameter ratio is equal to the valve port diameter over the nominal inside diameter. For non circular valve ports, use the square root of the internal area ratio (the square root of the valve port area over the nominal internal area).
Minor loss factors are calculated for:
- Av (SI) flow coefficient - the flow in cubic meters per second fluid density 1 kilogram per cubic meter which gives a pressure drop of 1 Pa
- Cv-uk (UK) flow coefficient - the flow in UK gallons per minute of water at 60 degrees F which gives a pressure drop of 1 psi
- Cv-us (US) flow coefficient - the flow in US gallons per minute of water at 60 degrees F which gives a pressure drop of 1 psi
- Cv-met (Metric) flow coefficient - the flow in liters per minute of water at 16 degrees C which gives a pressure drop of 1 bar
- Kv (EU) flow coefficient - the flow in cubic meters per hour of water at 16 degrees C which gives a pressure drop of 1 bar
- Cv* the dimensionless US flow factor = Cv-us / din^2 (din is the inside diameter in inches)
- K factor - the ratio of pressure loss over the dynamic pressure
- Cd or discharge coefficient - the ratio of the actual flow rate of the fluid through the fitting over the frictionless flow rate.
The calculated values are typical. Manufacturers data should be used if it is available.
Reference : Crane Technical Paper 410M Metric Version : Flow Of Fluids Through Valves, Fittings And Pipe
Change Module :
Related Modules :