火星大气来流模拟装置CFD仿真与试验

根据我国火星着陆巡视器工作过程,其着陆发动机需要在相对火星大气高速迎风运动中可靠点火。由于巡视器着陆时发动机喷管出口气流与火星稀薄气流方向相反,目前无法通过理论计算准确获得着陆过程的动态流场对发动机起动过程的影响量值。为验证火星着陆环境下发动机点火的适应性,需要建立发动机的火星大气来流试验环境模拟条件。为模拟发动机在火星大气条件下的相对运动,在真空舱内发动机保持固定,前端设置环形来流形成装置,该装置在发动机喷管周围形成一定速度的逆向来流包络。采用数值模拟技术结合试验验证方法,在火星着陆器巡视器主发动机性能考核试验中,针对来流的形成装置开展了设计研究工作。来流模拟试验测试数据表明:在确保贮箱供应压力稳定的条件下,来流模拟系统能够形成100~200 m/s速度的稳定来流,发动机在来流下能稳定启动工作,真空舱压力满足试验要求。

CFD and experimental studied on the Mars atmosphere incoming flow equipment

According to the orbit and land detector working process,the landing rocket engine needs to be ignited steadily when the detector is landing toward the surface of the Mars.Due to the shortage of theoretical method which can be used to evaluate the accuracy effect of dynamic reverse flow flied to the rocket engine when it started,the experimental test and evaluation platform were needed to be built to test the starting adaptation of the rocket engine of the detector for the atmosphere of Mars.In order to simulate the relative velocity between the rocket engine and Mars atmosphere,one atmosphere incoming flow equipment were set towards to the outlet of the nozzle of the engine which fixed in the vacuum chamber.The equipment can generate a certain speed of atmosphere incoming flow to the nozzle.Based on the CFD and experimental test method,the CFD and experimental analysis for atmosphere incoming flow equipment were studied in the testing process for the rocket engine of Mars detector.The testing data show that the stable atmosphere incoming flow of 100~200 m/s can be generated through the equipment,the rocket engine can start stably under the incoming flow condition and the pressure of the vacuum chamber was retained under the requirement of the test.