Dear All,
I have Natural gas compression simulation project. There is a blowdown valve on inlet separator vapor line which directs depressurization to HP flare header when emergency ... I am using API 520 method for getting the flow through the orifice.. Equation i am using is
If the
pressure ratio is greater than the critical, the flow is NOT choked:But my case is choked flow case, as pressure downstream is lower as flare header around 7 barg and upstream is at 13 barg...
here, I have a doubt, like flowrate through the BDV i m getting is around 50,000 kg/hr wherein process line which goes to next equipment flow is 10,000,00 kg./hr , upstream pressure is 13 barg, MW is 22.057, sp gravity is 0.013, K= 1.270( ratio of specific heat, PSV inlet line siz is 6 inch, outlet is 10"
Is this flowatte ok?
Request help here..
I am using API 520 equation for choked flow for modelling restriction orifiece and PSV also .. only thing is that BDV RO Op is 100% always and PSV opening changes from 0 to 100% based on inelt presure,,
Regards,
Chetan Chavan