Help:Pressure calculation in Fluent 6.3
 

Hi, everybody

I am doing simulation of flame propagation in closed vessel using progress variable. The solver is density-based solver. When I use the explicit unsteady formulation, the pressure rise is reasonable. However, when I use the implicit unsteady formulation, the pressure increase rather slightly (almost no increasing), and the temperature became higher. Why this happens? Could anyone help me work out the problem? Thank you very much

Can any one help me? By the way, I find that the mass conservation is not good, some mass has been lost.

What can I do?

Thanks.