Hi everyone!

I'm trying to simulate a heat transfer by conduction, convection and radiation on Flowsimulation. When I only simulate conduction and convection, everything is fine. When I include radiation in the basic setup but with only nonradiative surfaces, everything is fine. But When I start to include radiative surfaces with an emissivity, I have a negative temperature where I'm supposed to find around 300K. Does anyone has an idea? Thank you!