The problem about convergence
 

Hi all,

I am simulating a isothermal jet flow inside a room,due to the reason of either unknown inlet velocity profile or uniform velocity,i use mass flow rate as inlet boundary condition and outflow condition at exhaust.

From the residual monitor recording, the residuals become steady, but form the outlet surface monitor, mass flow rate is fluctuating all the way with wide range and can't converge.

Does anybody know what's the problem?

Thanks!