Two temperature solutions cannot be post processed if NaNs exist in the solution file.

[uqngibbo]

Nils Temme has noted that if a two temperature simulation crashes with a NaN in either T or T_modes, Eilmer will correctly write out the solution file with the NaN in it. However, attempting to post process this file results in an uncaught FlowSolverException, which means the file cannot be viewed to figure out where the NaN is.

[uqngibbo]

Could not reproduce.