[jalay]

Hi all,
I am final year student and i am working on simulation of gas diffusion in case of leakage in the lab.

In that case i am using pressure based solver with k-epsilon model and species transport.
And if I give boundary all conditions (i.e. Air inlet , gas inlet , ventilation) as pressure the solution converges and results can be seen in cfd-post as velocity contour, but when i give gas inlet as a mass flow inlet the result is not converging and even I can't see the mass fraction of gas in cfd-post.

And I tried with density based solver with explicit, But the results are same.
Please guide me what should i do??
Which mistake i have done?