侧向喷流与飞行器三维绕流干扰流场特性的DSMC/EPSM数值模拟

采用DSMC/EPSM混合算法,研究了带有侧向喷流的复杂外形高超声速飞行器稀薄区和连续区三维混合流场的干扰特性。采用一种飞行器物面网格与DSMC计算域网格分别标识的方法,通过判断模拟分子与表面碰撞来完成飞行器物面网格与DSMC计算域网格间的信息传递和信息存贮,对于复杂外形飞行器的精确描述的物面网格不需做进一步处理,直接应用于不依赖于飞行器外形的DSMC计算的通用子程序中。引入碰撞数做为混合参数,对流动区域进行划分,并通过网格中碰撞数的统计和处理,有效地将DSMC和EPSM方法结合在一起。仿真计算了三维复杂外形飞行器带喷流流场压力、热流分布量,飞行器表面气动力、气动力矩和气动热参数,对喷流与高超声速空气绕流相互作用以及它们与物面之间的相互扰动进行了分析,证明了采用的方案和技术的有效性。

The hybrid code of the Direct Simulation Monte Carlo and the Equilibrium Particle Simulation Method on three dimensional flow field interacting with the side jet

The hybrid code of the Direct Simulation Monte Carlo Method and the Equilibrium Particle Simulation Method was used to sudy the hypersonic three dimensional flow of the vehicle wih the side jet.By marking respectively the surface position elements and the space cells,the transferring and storing of information between the surface position elements and the space cells had been implemented by judging the molecules collision with the surface.In particular,the problems encountered in describing exactly the surface position element to calculate aerodynamic heating and pressure distribution in the DSMC method had been solved.The pressure,temperature and velocity distribution of the flow field are studied.The impacts of the side jet on the structure of flow field are analyzed in details.The analysis of simulation results confirms the validity of the suggested scheme and techniques.