Dear all, I have a question regarding radiation from surfaces. I am working on a model where two parts, axisymmetric, slide one against other with a fixed pressure. This produce heat at the interface used to produce a weld. Now I am quite happy with my model, but I understood that two forms of heat loss are important. Convection and radiation, both to the environment at around 20/23 Celsius degree. Now my problem is that the step that I am using is a coupled displacement-thermal analysis and the only option for radiation that I can choose is "surface radiation". Theoretically this would be fine for my case, since my external surfaces will exchange heat with the surrounding space. However, the emissivity that I can use is a FIXED value, instead in my case it should change with the temperature. The only way to have emissivity as function of temperature is to create an interaction property. Sadly this can be used only with "cavity radiation" which I cannot use in a coupled analysis, and I even do not know if it is correct, since I do not have a cavity.

Does anyone know how to allow the emissivity to being temperature dependent when surface radiation is used?

Many thanks!