Direct Simulation Monte Carlo for Atmospheric Entry. 1. Theoretical Basis and Physical Models.

摘要

The direct simulation Monte Carlo method (DSMC) has evolved over 40 years into a powerful numerical technique for the computation of complex, nonequilibrium gas flows. In this context, nonequilibrium means that the velocity distribution function is not in an equilibrium form due to a low number of intermolecular collisions within a fluid element. In atmospheric entry, nonequilibrium conditions occur at high altitude and in regions of flow fields with small length scales. In this first article of two parts, the theoretical basis of the DSMC technique is discussed. In addition, the methods used in DSMC are described for simulation of high temperature, real gas effects and gas-surface interactions. The current status of the various models is reviewed and areas where further work is required are identified.