How is the rated CV value of a valve calculated?
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I would like to ask how to calculate the rated CV value of a valve. Apart from using experimental methods, is it possible to calculate it through software simulation? I’m a beginner, so I hope experts can help me out. Thank you
It’s definitely impossible to calculate it mathematically; either experimentation or simulation is required. In the case of simulation, pressure boundary conditions are applied at the inlet and outlet ends to determine the mass flow rate, and then formulas are used to make further calculations based on the results of the simulation
Something I found before, from a valve manufacturer.
Here’s something for your reference; it’s not very accurate, but the deviation for small diameters isn’t significant
Required: pressure difference, diameter, medium quality; calculation is possible
You can take a look at my homepage; there’s a selection and calculation software for adjustments
How is it possible that there’s no way to calculate it? It’s probably because you don’t know; basically, every manufacturer of control valves has its own calculation software
Valve manufacturers should be able to calculate based on operating conditions
Bro, the calculation software used in valve factories is designed to determine the Cv required under specific operating conditions, based on the known Cv values of valves; it is used for selection purposes. Please make sure you understand this concept clearly.
The calculation for operating conditions determines the CV required for those conditions, but what is being asked for is the valve’s rated Cv. The rated Cv is determined during the design process and then verified through testing. Then, based on the rated CV, each manufacturer has its own valve selection software; this software is used to calculate the CV required under the given operating conditions, and from that, the appropriate opening degree is determined