I have a part in vacuum that I intend to heat to and maintain a certain temperature. I want to see what the temperature gradient across the part will be so that I can determine the correct wattage. I am applying a wattage using a cartridge heater. The only mechanism for heat dissipation is radiation. The part is mounted on an insulator so conduction is negligible. The part will be in a small aluminum vacuum chamber, but the chamber is not part of the FEA model. I have a basic understanding of radiation, but I am not sure what the correct radiation settings are for this type of model. Any help will be greatly appreciated.