[fascinatedbyCFD]

Sir/madam,
I am trying to find the volume flow rate of Direction Control valve and it is a pneumatic valve with air as working fluid.

Now from CFX i get mass flow rate (Kg/s) and what density should i use to convert to volume flow rate the velocity is about 0.5 mach and density at outlet plane for the air is about 8 kg/m3.

When i use density as 8 kg/m3 i get only 1700 LPM which is very very low when compared to test results but when i use 1.185 Kg/m3 i get near 10000 LPM which is close to real time results.

Please help i am struck with this problem and may be so poor in basics.