A STUDY OF DEFFUSION IN A CHEMICALLY FROZEN IONIZED GAS

摘要

Heat transfer in an ionized gas is studied by comparing the results given by different diffusion models. The analysis is valid for ionized gases in which the Debye length exceeds a mean free path.nMulticomponent diffusion coefficients are employed in the equations to describe exactly the heat transfer in a highly ionized gas at rest between two walls maintained at different temperatures. A simplified model is developed which is valid for weakly ionized gases, and the ambipolar diffusion model is derived when the assumption of no charge separation is made.nSolutions for these models are obtained on a digital computer for various wall separations and compared with each other and with an analytic solution of the ambipolar diffusion model. It is concluded that, for problems in which the wall separation is large compared with the Debye length, the ambipolar model is adequate in predicting the heat transfer and the flux of charged particles.