Poiseuille flow and thermal creep in a capillary tube on the basis of the kinetic R-model

Abstract

Flow of a diatomic rarefied gas in a capillary tube of infinite length and an arbitrary cross-section under a given small pressure gradient (Poiseuille flow) or a small temperature gradient (thermal creep) is studied on the basis of a kinetic model that takes account for the rotational degrees of freedom of molecules (R-model). Numerical investigation is carried out for flows between parallel flat plates and in a circular capillary tube at the gas parameters corresponding to nitrogen. The main calculated quantity is the gas flow rate through a tube cross-section. The results are compared with the corresponding data obtained on the basis of the S-model.