Simulation of hypersonic flows in near-continuum regime using DSMC method and new extended continuum model

A new extended continuum model for simulation of rarefied hypersonic flows is developed in this paper. A parameter Zh which can characterize the non-equilibrium effect of shear flows is proposed through analyses of particle velocity probability density function via Direct Simulation Monte Carlo (DSMC) method. The representative shear stress and representative heat flux are modeled through an effective viscosity and an effective thermal conductivity. The relation between the effective transport properties and non-equilibrium parameter Zh is obtained from DSMC data in a typical shear flow, then it is embedded into the continuum model of Navier-Stokes equations. In order to valid the new extended continuum model, a hypersonic flow of Argon over a blunt flat-plat at a global Knudsen number of 0.0036, Ma number of 15 is simulated by the DSMC method and the proposed Data improved Navier Stokes model (DiNS).