Transport phenomena in a completely ionized gas with large temperature gradients

A solution to the Boltzmann equation is found that extends to large gradients and fields the classical Chapman-Enskog approximation developed by Spitzer and collaborators for electron transport in a fully ionized gas. The extended solution is used to calculate correction factors to the classical transport coefficients of a nonuniform plasma that depend on the temperature-gradient scale length as a parameter. These factors lead to inherently flux-limited heat flow with values in close agreement with Monte Carlo and numerical Fokker-Planck calculations.