Why Fluent Solver Wrong?

Prakash

Dear CFD Users

I would like to ask one of the CFD, FLUENT solver problem which I faced in my project.

I am solving a problem with two gas mixing in 3-D, the 1st gas is mixing in 2nd gas by fraction of amount with time through small opening. The Boundry is fully closed.

Problem: suppose, I consider the 1st gas pressure higher that the 2nd gas preassure (P1>P2) and T1<T2 in these conditions the solver is showing unrealistic variation in pressure and T1>T2, the results are realistic and convergency. Why this situation is happening in FLUENT solver? can you advise me, how to overcome this problem.

your suggestions are appereciate in advance

regards

Prakash