低温推进剂过冷技术研究

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%. 

Study on subcooled technology for cryogenic propellants

Three subcooled methods,including the subcooled technology of heat transfer,pumping down decompression and injecting cooled helium for cryogenic propellants were summarized.By comparing advantages and disadvantages of three methods,the subcooled technology of pumping down decompression was recommended to be used on the entire loading process of ground.Based on thermodynamics theory,expressions of consumption,refrigeration capacity,pumping down time and lowest pumping speed were derived for the subcooled technology of pumping down decompression.The researches showed that consumption of cryogenic propellants was mainly used for its temperature drop,then the proportion for offsetting external leakage heat and special heat of tank material was very small,for instance,the relative consumption of its temperature drop,special heat of tank material,and external leakage heat for liquid hydrogen was 10.94％,0.38％,0.098％,respectively.The arithmetic accurately calculating consumption of cryogenic propellants was recommended to reduce launch costs of launch vehicle and enhance utilization of cryogenic propellants.Compared with the exiting formula,its relative error was 18 ％.