[chriss85]

I'm trying to simulate a problem which involves heat transfer from a very hot gas (plasma) in a wall. Concerning this problem, my solver is basically a merged version of sonicFoam and chtMultiRegionFoam (only the heat transfer part). The plasma has a large radiative flux and the wall isn't a very good heat conductor, so melting and evaporation occurs in reality.

I'm using the compressible::turbulentTemperatureRadCoupledMixed boundary condition that considers heat conduction and radiative heat fluxes through the boundary. This boundary condition always results in a temperature at the patch of 0 K...
I've tried various things, increasing iterations and using relaxation factors but without success.

The temperature will start with a negative (!) value at the patch in the iteration procedure and converge against 0 K in a few steps. The alpha value in the code of the BC will start oscillating with an increasing amplitude.

Using the compressible::turbulentTemperatureCoupledBaffleMix ed BC, the solution will converge, but since the radiation isn't considered this BC is not applicable to my problem.

I would expect the total heat fluxes to be the same on both sides of the patch when converged to satisfy energy conservation.

Any ideas for this?

You can also take a look at my related topic here: http://www.cfd-online.com/Forums/ope...pling-bcs.html