Karthik R
In order to have internal emissivity modeled at the walls, you will need to turn on Radiation. Turning on radiation will of course have its consequence as it will add another mode of heat transfer. So, you will need to worry about that. nBut, when you turn on the radiation, the radiation conditions at the wall will automatically ensure an equilibrium condition at the wall boundary. nI'd carefully check how your radiation is interacting with other models.nThanks.nKarthikn