[jose_rodrig]

Hi

I am simulating a combustion chamber for flameless combustion with the outlet boundaries pretty close to the inlet boundaries.

When I ignite the mixture, the simulation diverges (the temperatures get higher and higher) as the hot air gets closer to the outlet. I checked on the solution right before the crash and I saw that the outlet temperature did not changed as the hot gases approached with temperatures 2000k higher.

1) I am setting zeroGradient in this boundary, which should allow the outlet temperature to raise with the outgoing gases. Am I right??

2) Also, a colleague suggested me use extrapolation to set the boundary values. How does OpenFoam do extrapolation for BCs?

3) What does $internalField do? For example in the dictionary

Outlet
{
    type    fixedValue;
    value   $internalField;
}

I am stuck in this for a while and I need to move forwards as this work is for my thesis and I dont have a lot of time now.
Thx