[Roman1]

Hello all. I would like to have your help in writing BC for the correct calculating WallHeatFlux.I use
the latest OpenFoam on Debian, solver - fireFoam. In order to save the space and the memory I give the short description of my case.
The basis for the case was taken from the OpeFoam tutorial.
There is the fire compartment 5x3x3 with a gap under the door.Fire source is a patch (1m x 1m) with the BC "flowRateInletVelocity",
total heat release rate of the fire is 100 kW (according to the time dependent BC). I tried mesh with the cell size from 10 sm to 30 sm.
BC for the wall: U-fixedValue (0 0 0), p and p_rgh-zeroGradient. For T I tried fixedValue and inletOutlet with inletValue 300. I tried many
different BC for other parametres and also tried different models - Les (Smagorinsky), RAS (kEpsilon,LRR, laminar). Finally it turned out that
the most combinations of BC and models gave very similar result. But it was uncorrect. Flow direction was inside the compartment. Utility WallHeatFlux
gave the negative value. The only way to fix the situation that I managed to do was the decreasing of the Courant number to 0,05-0,15. After that
WallHeatFlux gave almost zero values and flow direction became correct. Now I have some questions that I am in no condition to answer (because of a
headache after a month's work withot any result).
1. What does OpenFoam need to correct calculate WallheatFlux that takes place in real fires (50-500 W per m2 for ex.)?
2. How can I arrange the calculation of wallHeatFlux with the help of BC "convectiveHeatTransfer"? Should I use some BC for T or other way?
3. Is externalWallHeatFluxTemperature the boundary condition for T or for wallHeatFlux?
4. I noticed that the dQ-monitor gives different values for different cell sizes and other parametres but the pictures (results) of fire are the same.
Is that normal?
I need the help much. Thanks.

[Roman1]

Hello. Does anybody, who familiar with the solver FireFome (OF), have a little time to run the attached case and give an advise about it? I would be very be grateful. Thanks