高超声速气流非结构化网格DSMC算法研究

高超声速气动热力学环境的研究是直接涉及飞行器轨道控制、热防护设计的关键问题之一。文章通过研究稀薄气体热化学非平衡态中的热力学环境,采用非结构化DSMC程序对"火星探路者号("Mars Pathfinder)探测器的Ballute减速装置在地球大气层和火星大气层中的高超声速飞行进行了数值模拟,计算得到了流场的温度分布、探测器壁面的热流密度分布,分析表明稀薄气体热化学非平衡态对飞行器流场有影响。将仿真结果与NASA兰利研究中心的计算结果作了比较,二者吻合很好。研究结果可用于飞行器热防护设计。

DSMC method of unstructurized grids for hypersonic gas now

The hypersonic aero-thermodynamics is important for the flight control and the vehicle thermal protection system （TPS） design. This paper firstly studies the thermodynamic environment in the thermochemical nonequilibrium flow. Unstructurized girds are used to simulate the towed Ballute flight in the Earth atmosphere and the Martian atmosphere by DSMC. Important parameters of the hypersonic vehicle, including the thermochemical nonequilibrium characteristics and the wall heat flux, are obtained by the numerical simulation. The obtained results are compared with the computation results published by NASA Langley research center, and a good agreement is found. These results are useful for designing related vehicles＇ TPS.