低温推进剂重定位推力幅值及时序优化

Thrust Amplitude and Time-Series Optimization of Cryogenic Propellant Reorientation

为了减少重定位时间及推进剂消耗量,提升低温末级的机动性及运载能力,采用流体体积函数(VOF)方法开展重定位推力幅值及时序优化研究,分析重定位过程推进剂质心高度、平均动能、卷气率以及平均气泡直径的变化规律,以获得不同推力幅值及推力时序下的重定位时间和推进剂消耗量。结果表明:小推力重定位时间长,推进剂消耗量少;而大推力重定位时间短,推进剂消耗量多。通过合理优化推力时序可以有效减少重定位时间及推进剂消耗量。

In order to reduce the reorientation time and the propellant consumption,improve the mobility and carrying capacity of the cryogenic upper stage,a numerical simulation of reorientation employing volume of fluid(VOF)method is applied to investigate the thrust amplitude and time-series optimization of reorientation process,the reorientation time and propellant consumption are obtained by analyzing the variation of the propellant mass centre height,the average kinetic energy,the entrained gas ratio and the average bubble diameter.The results show that the reorientation time with the low thrust is longer than the reorientation time with high thrust,but the propellant consumption with low thrust is less than the propellant consumption of high thrust;The reorientation time and propellant consumption can be effectively reduced by reasonably optimizing thrust time-series.