THE TREATMENT OF NONLINEARITIES IN FLUX-LIMITED DIFFUSION CALCULATIONS

The flux-limited diffusion equation describing radiative transfer cont ains inherent temperature nonlinearities, as well as nonlinearities as sociated with its flux-limiting character. The common practice in time -dependent calculations is to treat these nonlinearities explicitly. I n this paper, the increase in accuracy obtained by iterating these non linearities is investigated. The issue of what the best choice for the fundamental material energy field variable, namely the temperature or its fourth power, is has been addressed.