Numerical and theoretical study of gaseous flows in a micro tube

Abstract

The 3-D axisymmetric, steady flow in a micro-tube with Kn number in the 'slip flow' regime is investigated by analytical method and DSMC (direct simulation Monte Carlo) approach. The analytical formulations are derived by dimensional analysis. Under different pressure ratios of the inlet to outlet, the streamwise velocity, nonlinear pressure distributions and volumetric flow rates along the streamwise direction are obtained analytically, which are compared with those given from DSMC computation. Good agreement was achieved. The causes of deviation in pressure distributions between analytical and DSMC results are discussed in terms of compressibility and rarefaction effects.