Grey and multigroup radiation transport models for two-dimensional stochastic media with material temperature coupling

Current theories for approximating the effects of stochastic media on radiation transport assume very limited physics such as one dimension, constant grey opacities, and no material energy balance equation. When applied to more complex physical problems, the standard theory fails to match the results from direct numerical simulations. This work presents the first direct numerical simulations of multigroup radiation transport coupled to a material temperature equation in a 2D stochastic medium that are compared to closures proposed by various authors. After extending it from grey to multigroup physics, one closure that is not commonly used successfully models the results in dilute systems where one material comprises less than 5% of the total. This closure is more accurate for related grey transport problems than it is for the multigroup problem. When the specific heats are material- and temperature-dependent, it is much more difficult to fit the direct numerical solutions with an approximate closure.

► The standard closure for stochastic media transport does not work well in 2D. ► An alternate closure works well for multigroup transport in dilute media, <5%. ► This closure works better for grey transport than multigroup transport. ► Adding a material temperature equation makes stochastic media much harder to fit.