Heat Transport with Cold and Hot Electrons Allowing for Flux Limitation by Shvarts' Method

摘要

The analysis of Shkarofsky is extended to include a variable degree of collisionality and gradient scale length using the method of Shvarts et al. The perturbed electron velocity distribution is limited in magnitude to the unperturbed part when the former becomes larger than the latter. A Maxwellian distribution is adopted for the hot electrons. For the cold electrons, either a Maxwellian (exp(-v exp 2 /v/sub c/ exp 2 )) or an exp(-v exp 5 /v/sub c/ exp 5 ) variation is used. The heat flow has coefficients proportional to gradients in cold and hot electron density, to gradients in cold and hot electron temperature and the free streaming contribution. These contributions are summed for two sample sets of scale lengths. One set of results shows that in an intermediate range of collisionality, the heat conduction and flux limiter are substantially decreased and the heat flow may even change direction. (ERA citation 08:013467)