Abstract
Flow characteristics of gas through micro/nano-filters are studied in present paper using the Burnett equations with slip boundary conditions. A simplified two dimensional filter model is proposed. The results calculated from the Burnett equations are first compared against the corresponding results of the direct simulation Monte Carlo method and these two results agree very well with each other. The difference between the results of the Navier-Stokes and the Burnett equations increases with the increase of Knudsen number. The variations of non-dimensional pressure drop with Reynolds number, the opening factor and the ratio of the filter thickness to hole diameter are presented. The non-dimensional pressure drop is independent of Knudsen number. A modified scaling raw was proposed at last according to the numerical results.
Keywords: Micro/nano-filter, Burnett equations, velocity slip, transition regime, rarefied effect, nanoflow, Reynolds number