[fireman]

Hello, everybody,

I am doing simulation of deflagration in a tunnel (flame propagation of premixed mixture). The mixture is ignited at one closed end of the tunnel. First, the Mach number <0.1, however,the flow velocity increase fast with time, and the Mach number also increase to a number larger then 0.1.

The reaction flow is treated as compressible flow.

The problem is how should I set the operating pressure in FLUENT6.3.26?
It's suggested in Fluent that when Mach number <0.1, operating pressure=mean flow pressure, while when Mach number >0.1, operating pressure=0 or mean flow pressure.

So what can I do.？
By the way, I use the density-based solver, so I can not use the floating operating pressure.

Thanks very much!