MULTIFLUID DESCRIPTI ON OF RAREFIED GAS M IXTURE FLOWS

Abstract

In the present contribution attention is focused to extendthe application of multifluid descriptions torarefied conditions for the first time . To this aim, a multifluid Maxwell model and a multifluid Smoluchowski modelare proposed for near wall behavior of the constituents of a rarefied gas mixture. Afterwards, multifluid balanceequations in conjunction with these boundary conditions are solved for some slip flows of binary gas mixturesbetween parallel plates T he co rresponding results are compared with those of a previously developed Navier Stokessolver. Inspection of the results indicates that while the Navier Stokes equations may lose their accuracy under highrarefaction, non equilibrium features are properly cap tured by developed multifluid description. This successfulmethod is thereafter utilized to discuss the consequences of velocity slip, the tangential momentum accommodationcoefficient, and mass disparity of the mixture constituents on the degree of non eq uilibrium between the constituentsof the gas mixture s between parallel plates.