HOw to match the Mach number in FLUENT??
 

How can i match a particular Mach number for simulating a case in FLUENT??
My BCs are:- mass flow inlet, pressure outlet..
I cant give velocity inlet as the inlet condition since my flow is rarefied compressible flow with nitrogen as the fluid..
THe cases which i hv simulated, im getting a difference between the experimentally calculated Mach no and Mach no from FLUENT..SO i want to match that..HOw can i do it??