Viscous drag and heat transfer in non-stationary gas flow between rotating cylinders

Abstract

The viscous drag (wall shear stress) and heat flux on the both cylinder walls, as well as flow macroscopic characteristics (velocity, density and temperature) are numerically studied in non-stationary Couette gas flow between rotating cylinders. The results are obtained using Direct Simulation Monte Carlo (DSMC) method and numerical solution of a continual model based on the Navier-Stokes-Fourier (NSF) method. Three typical cases are considered: A) inner rotating - outer stationary cylinder; B) inner stationary - outer rotating cylinder; C) opposite rotating cylinders. These studies have been accomplished for fixed Knudsen numbers. The NSF results have been obtained by setting a local value of Knudsen number in the corresponding first order slip boundary conditions. Capabilities applications of continual model are estimated for several Knudsen numbers.