Create a THM component that can perform general radiation heat transfer between 2D heat structures

[joshuahansel]

Motivation

Sockeye has a validation problem where a heat pipe is welded to multiple heater pipes, and there need to be a way to couple these via radiation. Currently there is only a radiation coupler that assumes that the surfaces are concentric cylinders, but in this case we have adjacent cylinders that form 3-pipe enclosures.

Design

This would create a new component that can perform heat transfer between a temperature on one 2D cylindrical heat pipe surface with temperatures on adjacent heat structures at the same axial level.

Impact

New component.