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综述了低温推进剂3种过冷方式(换热过冷、抽空减压过冷和冷氦气鼓泡过冷)的过冷机理,并对比分析了其利弊,在地面全过程过冷加注时推荐采用抽空减压过冷对低温推进剂进行冷却.基于热力学理论推导了低温推进剂抽空减压过冷时耗液量、制冷量、抽空时间和泵最低抽速的表达式.研究得出低温推进剂耗液量主要用于自身温降,抵消外部漏热和贮罐材料比热容所占比例很小,如液氢自身过冷、材料比热容和外部漏热所占的相对耗液量分别为10.94%,0.38%,0.098%.推荐采用变物性算法来精确计算低温推进剂耗液量,可降低运载火箭发射成本,提高低温推进剂利用率,与现有公式对比,其相对误差为18%.
The overcooling mechanism of three kinds of supercooling methods (subcooling, subcooling, depressurizing and supercooling of cold helium) of cryogenic propellants was reviewed. The advantages and disadvantages were analyzed and compared. It is recommended to use the evacuation overcooling to cool the cryogenic propellant.The expression of liquid consumption, cooling capacity, evacuation time and minimum pumping speed of the cryogenic propellant during evacuation under pressure and supercooling is deduced based on the thermodynamic theory. The consumption of cryogenic propellant is mainly used for its own temperature drop to offset the external heat leak and the proportion of specific heat capacity of the tank material is very small, such as liquid hydrogen itself is too cold, the specific heat capacity and external heat leakage accounted for relative fluid consumption 10.94%, 0.38%, 0.098% .It is recommended to use the variable property algorithm to calculate the liquid consumption of cryogenic propellant accurately, which can reduce the launching cost of launch vehicles and improve the utilization rate of low temperature propellant. Compared with the existing formula, the relative error is 18% .