Numerical Investigation of Shock Tube Flow under Rarefied Conditions

Two‐dimensional Direct Simulation Monte Carlo (DSMC) simulations are carried out for investigating the shock wave propagation and boundary layer effects in a shock tube flow, for a wide range of rarefied conditions. Nitrogen is used for all simulations. The Cercignani‐Lampis‐Lord (CLL) model of gas surface interactions is implemented to study the effects of boundary layer which develops behind the moving shock front. The effect of surfaces is analyzed with different tangential momentum accommodation coefficient (TMAC) values in the CLL model. The Larsen‐Borgnakke (LB) model of inelastic collisions is implemented for diatomic gases. The shock front deceleration and the contact surface acceleration phenomena due to viscous effects are studied. The simulation at higher Knudsen number flows shows disappearance of the shock front and the contact surface.