Predicting Flashing Flow Through Relief Valve
Predicting Flashing Flow Through Relief Valve
(OP)
Is there a good procedure for predicting flashing flow through a pressure relief valve? Would you just predict pressure drop through the valve and see if the pressure drops enough to get the liquid to boil? Or do you need the critical temperatures and pressures?
Thanks.
Thanks.





RE: Predicting Flashing Flow Through Relief Valve
RE: Predicting Flashing Flow Through Relief Valve
The process is adiabatic and isenthalpic.
h1=x*hg2+(1-x)hl2
h1 is the inlet enthalpy
hg2 is the enthalpy of the gas phase at the discharge pressure.
hl2 is the enthalpy of the liquid phase at the discharge pressure.
Percent flash is usually pretty small. But if you convert to density, with the expansion as the fluid flashes to gas, the outlet mist is pretty light and goes very fast.