Hi everybody I have modelized three fluids cavity separated by solids wall the fluids is in natural convection I fixed different temperature at the extremity of my geometrie All boundarie conditions expect hot and cold side are adiabatic I simulated it in2D and 3D model

When I measured the flux at cold and hot side I don't have the same . How can it possible that I lost one parts of this flux. I have try different mesh and different conductivity for fluid and solid .It seems that the flux difference depends of the conductive ratio between solid and fluid.

Someone can help me? Thanks everybody.

If you are solving unsteady problem then it is possible that the thermal energy is being stored in the fluid and therefore their temperature rises. In this case you will not get the same heat flux at the boundaries.

Saad

Thanks for your answerd but I am in sationary problem. And there are the same problem whith other CFD code like Fenlab