火星低气压环境下的尘暴模拟研究

Numerical and Experimental Simulations of Martian Dust-Storm in Low Pressure Environment

通过地面模拟试验来验证尘暴环境对探测器性能的影响,对我国开展火星探测任务具有重要的意义。本文提出了一种火星尘暴环境模拟系统方案,为便于进行尘暴流场的数值模拟,建立了尘暴热物性参数计算公式,完成了尘暴发生装置气动结构设计及建模。火星尘暴模拟分析结果显示:在压力为600 Pa,温度为233 K,沙尘体积分数为2.6×10^(-8)时,尘暴速度可达74 m/s;温度对流场品质影响较小;压力增大时,流场均匀性变差、速度梯度增大。本文研究成果可为进一步开展火星尘暴环境模拟系统研制提供技术支持。

The flow-field of the dust-storm,occurring in Martian low pressure environment,was mathematically modeled,theoretically analyzed,and numerically simulated for design optimization of the lab-designed experimental simulation system. The impact of the simulated dust-storm environment,including the pressure,temperature and dust volume fraction,on the flow-field uniformity,velocity profile,thermal and aerodynamic properties of the dust-storm,was investigated. The simulated results show that the flow-field significantly depends on the pressure and dust volume fraction,but weakly on the temperature. As the pressure increases,the velocity gradient increases and the uniformity of flow field deteriorates. At 233 K and a pressure of 600 Pa with a dust volume fraction of 2. 6 × 10^（-8）,the dust-storm velocity in the simulation system was estimated to be 74m/s. We suggest that the simulation be of some technological interest in the development of ground experimental system for China＇s Mars exploration project.