[rudyy]

Hello,

I am trying to solve a problem of heat transfer in a bundle of wires using Ansys Fluent. Since I don't have Joule heating available, I am modeling the current as a heat source (in W/m³). For now I am just modeling one cable to ensure proper setup. I have D.O. radiation enabled.

However, I am unable to get consistent results. I tried making two 2-D geomtries with different size enclosures to test the effect of my BCs. Using temperature to define the walls of the enclosure obviously has a direct effect on the heat conduction away from the wire by lowering the ambient temperature. (I say conduction because, although the wire is in "air", the air is stagnant in the model.)

Instead, I believe the correct BC is a heat flux of 0 W/m² on the outer walls of the enclosure, and a heat source on the disc representing a cross section of the wire. I am still getting inconsistent results between my different sized enclosures.

Can anyone find the error in my setup? Perhaps I just need better convergence?

Thank you for any help