This is what solidworks has t osay on the issues The SOLIDWORKS® Flow Simulation software assumes that the heat radiation from the solid surfaces, both the emitted and reflected, is diffuse (except for the symmetry radiative surface type). This obeys the Lambert law, according to which the radiation intensity per unit area and per unit solid angle is the same in all directions. The solar radiation is absorbed and reflected by surfaces independently from thermal radiation from all other heat radiation sources. The propagating heat radiation passes through a solid specified as radiation transparent without any refraction or absorption. You can specify a solid as transparent to the solar radiation only, or transparent to the thermal radiation from all sources except the solar radiation, or transparent to both types of radiation, thermal and solar. The project fluids neither emit nor absorb heat radiation (they are transparent to the heat radiation), so the heat radiation concerns solid surfaces only. The radiative solid surfaces that are not specified as a blackbody or whitebody are assumed an ideal graybody, that is, having a continuous emissive power spectrum similar to that of blackbody, so their monochromatic emissivity is independent of the emission wavelength. For certain materials with certain surface conditions, the graybody emissivity can depend on the surface temperature.

@@goengineer Thank you! I think ANSYS also follows the same Lambertian heat distribution as SolidWorks right?

There isn’t a way to look up the view factor from the analysis as Flow Simulation uses a ray model for radiation but there is a forum article that talks about how you can extract this value : forum.solidworks.com/thread/245723 . Thank you.

@@goengineer Hi thankyou for the hint! Thats me asking in that forum :)