文献类型：期刊文献

中文题名：HAN基单组元推进剂热分解过程的分子动力学模拟

英文题名：Molecular dynamics simulation of thermal decomposition mechanism for HAN based monopropellant

作者：黄永民[1];李旭博[1];胡旭[1];周秀爽[1]

机构：[1]华东理工大学化学与分子工程学院,上海200237

年份：2024

卷号：50

期号：5

起止页码：106

中文期刊名：火箭推进

外文期刊名：Journal of Rocket Propulsion

收录：CSTPCD;;北大核心:【北大核心2023】；

基金：上海市青年科技英才扬帆计划(21YF140800)。

语种：中文

中文关键词：单组元液体火箭发动机;HAN基推进剂;分子动力学模拟;ReaxFF/lg;热分解

外文关键词：monopropellant liquid rocket engine;HAN-based propellant;molecular dynamics simulation;ReaxFF/lg;thermal decomposition

摘要：为揭示非催化点火方式的硝酸羟胺(HAN)基单组元液体火箭发动机内推进剂的反应机理,采用分子动力学模拟方法,在ReaxFF/lg力场下对HAN基推进剂热分解机理及配方影响作用机制开展研究。计算结果表明:推进剂热分解过程存在两个阶段。第一个阶段为吸热阶段,推进剂内硝酸羟胺和硝酸肼氢键断裂,分解生成羟胺、肼和硝酸,吸热阶段主要受推进剂内氢键个数影响;第二个阶段为推进剂分解反应阶段,由硝酸和羟胺的分解所引发,生成NH_(2)、NO_(2)和OH。OH为主要的氧化性物质,与肼、甲醇反应,生成大量的水。肼在推进剂中的分解主要依靠与OH反应脱氢,生成N_(2)H_(3),并最终分解形成N_(2)和H_(2)。推进剂配方仅对与OH的反应有显著影响。降低甲醇的含量,能够显著提升燃料的反应速率,同时促进肼分子的反应脱氢,提高推进剂初始分解速率;提高硝酸羟胺的含量能够促进甲醇的分解,但受肼分解反应速率较低的影响,推进剂整体分解速率降低。
In order to reveal the decomposition mechanism of hydroxylamine nitrate(HAN)based monopropellant in non catalytic monopropellant liquid rocket engine,molecular dynamic simulation method based on ReaxFF/lg force field was used to study both thethermal decomposition mechanism and the influence of propellant formulation.The calculation results show that there are two stages in the thermal decomposition process of the propellant.The first stage is the endothermic stage,where the hydrogen bonds of hydroxylamine nitrate and hydrazine nitrate in the propellant break and decompose to form hydroxylamine,hydrazine,and nitric acid.The endothermic stage is mainly affected by the number of hydrogen bonds in the monopropellant.The second stage is the propellant decomposition stage,which is triggered by the decomposition of nitric acid and hydroxylamine,generating NH_(2),NO_(2),and OH.OH is the main oxidizing substance that reacts with hydrazine and methanol to produce a large amount of water.The decomposition of hydrazine mainly depends on dehydrogenation with OH,and generates N_(2)H_(3).N_(2)and H_(2)are the final products.The propellant formulation only has a significant impact on the reaction with OH.Reducing the proportion of methanol can significantly increase the reaction rate of fuel,while promoting the dehydrogenation of hydrazine molecules and increasing the initial decomposition rate of propellant.Increasing the content of hydroxylamine nitrate can promote the decomposition of methanol.However,due to the low rate constant of the reaction of hydrazine,the reaction rate of the propellant decomposition is reduced.