内置式深冷泵抽速计算及数值模拟研究

基于全舱布泵概念设计的内置式深冷泵是真空羽流效应实验中维持真空舱内动态真空度的关键设备.对基于麦克斯韦速度分布假设的内置式深冷泵抽速计算公式分析发现,该式不适用于带喷流的空间发动机羽流实验舱内的动态真空度和冷板面积计算.采用直接模拟蒙特卡罗(DSMC)方法对所设计的内置式深冷泵的抽速和真空舱内的动态真空度进行了数值模拟研究,结果表明DSMC方法在给定条件下能更准确地计算带喷流的空间发动机羽流实验舱内的动态真空度和冷板面积,计算结果与国外同类实验中空间发动机喷流流量与所需冷板面积的计算结果一致.

Direct Simulation Monte Carlo Study of Pumping Speed of Internal Cryogenic Fins

The impacts of the built-in cryogenic pumps,designed on the basis of the total chamber cryogenic concept,on maintaining of the dynamic pressure of the home-made,vacuum plume effect experimental system(PES) were analytically studied.The pumping speed of the built-in cryogenic pump,calculated by assuming Maxwell velocity distribution,fails to precisely evaluate the dynamic pressure and areas of the cooling-plate in the spacecraft with jet thruster.The pumping characteristics of the built-in liquid helium cryogenic pump were modeled and simulated in Direct Simulation Monte Carlo(DSMC) method.The simulated results show that DSMC simulation works fairly more accurate in calculating both the dynamic pressure and the cooling-plate area of the spacecraft with jet thruster.The calculated results were found to agree very well with those reported by international research groups.