SVV
Ansys Employee

Hi,

Are you getting this high temperature at the initial iteration? If yes, you can neglect it because as solution gets stable the correct temperature profile will be established.

Please make sure the mesh quality is good and also the material properties are correctly defined.

Can you elaborate on how you are setting the transmissivity to 1 at inlet for opaque surface? what is the temperature of fluid entering the inlet? Is the fluid flowing out?