In Bentley PULS, the rated valve loss is calculated based on the flow rate and valve diameter. Does the valve diameter correspond to the inner diameter of the suction valve or discharge valve? what's the formula used by the software to predict the rated valve loss?
Thanks
The formula comes from CRANE report. I believe it is rather difficult to estimate the pressure loss for every geometry so I would suggest calculate it outside PULS and input calculated value. The value of pressure loss I would suggest to calculate from compressor and valve manufacturer data. They assume that there must be some pressure loss to avoid valve flutter - see for example Hoerbiger paper here. It is assumed to be around 3% of suction pressure and 1.7% of discharge pressure, to keep the proper operation of valves, according to my knowledge.PDF
Best regards,
Maciej Rydlewicz, PhD Eng.
maciej.rydlewicz@softdesk.pl
+48 512206994
Answer Verified By: Mike Dattilio