This paper generalises an earlier result of Saffman (1960) to account for cross effects between turbulent and molecular diffusion for charged particle swarms in a gas in the presence of an electrostatic field. It is shown that turbulence enhances the anisotropic character of diffusion. The desirability of using a full kinetic theory analysis as against a limited hydrodynamic description of the swarm is discussed, and one possible tractable approach pointed out.
Kinetic theory analysis of rarefied gas flow through finite length slots