轻质烷烃混合流体固液平衡状态预测与致密化规律  

Prediction of solid-liquid equilibrium state for light alkane mixed fluids and associated densification effect

作　　者：刘柏文 王磊[1] 上官石 厉彦忠[1] 谢福寿[1] 马原[1] Liu Bowen;Wang Lei;Shangguan Shi;Li Yanzhong;Xie Fushou;Ma Yuan(Institute of Refrigerant and Cryogenics,Xi’an Jiaotong University,Xi’an 710049,China)

机构地区：[1]西安交通大学制冷与低温工程系,西安710029

出　　处：《低温工程》2024年第5期67-72,86,共7页Cryogenics

基　　金：国家自然科学基金(51876153,51976151)。

摘　　要：对比分析了多种轻质烷烃类混合流体凝固温度预测模型,发现正规溶液模型具有较高精度。采用该模型分别针对甲烷-乙烷、甲烷-丙烷二元混合流体的凝固温度及密度提升率开展了仿真分析。结果表明,对甲烷-乙烷体系,当甲烷摩尔含量为0.72时,体系达到最低凝固点,温度约72.90 K,相较于三相点纯甲烷,密度提升率为21.62%;对甲烷-丙烷体系,最低凝固温度存在于甲烷含量为0.66时,凝固温度为71.55 K,密度提升率34.48%。采用理想溶液模型预估了甲烷-乙烷-丙烷三元体系的混合特征。结果发现,当混合比为0.63∶0.17∶0.20时,凝固温度降至63.11 K,甲烷推进剂过冷潜能进一步提高。提供了3种混合流体相图,为液甲烷推进剂过冷制备、深度致密化提供了理论支撑。A comparison study indicates that the regular solution model has the highest accu-racy in simulating the freezing temperature of mixed propellant when compared to other models.Therefore,this model is used to predict the freezing temperatures and densification effect of meth-ane-ethane and methane-propane binary systems.It is found that methane-ethane system reaches the lowest freezing temperature of 72.90 K when the methane’s molar fraction is 0.72 in the mix-ture system.Compared to the pure methane at its triple point,the density increase rate of the mix-ture is 21.62%.For the methane-propane system,the lowest solidification temperature of 71.55 K occurs at the methane’s molar fraction of 0.66,and the density increase rate is 34.48%.Moreo-ver,an ideal solution model is used to predict the performance of methane-ethane-propane ternary system.It is found that when the mixing ratio is 0.63∶0.17∶0.20,the solidification temperature re-duces to 63.11 K,and the subcooling potential of methane propellant could be further improved.In addition,three-phase diagrams of the mixed fluids are given,which provide theoretical support for future the subcooling preparation and deep densification of liquid methane propellant.

关 键 词：固液相平衡 共晶点 致密化 正规溶液模型 

分 类 号：V511.6[航空宇航科学与技术—航空宇航推进理论与工程]