I ran a simulation with a part having air cavities for which I created air bodies to properly model the heat flux and temp distribution we were concerned about.  The second step is to run a stress analysis on using the temperature distribution, and it requires the same mesh (meaning all bodies included).

My question is since I need to apply mechanical properties to the air, and wanted to get opinion on if using extremely low E and nu values is appropriate (say .1 and .01).  There is a good temp difference (~100-degF) so expansion would be an issue with the solid part and I don't want false stresses imparted due to the 'solid gas'.  I don't have access to SW Flow, so a CFD temp plot isn't an option.  The chamber is very small anyway, and I would believe conduction is taking place but not in a highly influencing manner.

Thanks!