HAN基无毒单组元发动机热控研究

Study on thermal control of HAN-based greenmonopropellant thruster

为使某HAN基无毒单组元发动机正常工作,需采用一种高效的热控方式,保证点火前其催化床温度在200℃之上(远高于传统单组元发动机的点火温度)。以该HAN基发动机为研究对象,在制定的热控方案基础上,建立有限元模型,采用I-DEAS/TMG软件对该发动机各部件温度进行计算,之后按照产品状态进行发动机真空热试验,获取发动机重点部位的温度数据。结果表明:除前床后部外,其余位置温度测点的热分析和试验温度误差均小于4℃,认为两者吻合较好,有限元模型可用于之后的在轨温度预示等工作;该HAN基发动机身部采用安装一种新型铠装加热丝组件,而后覆盖不锈钢箔的热控方式,结合支架的镂空结构设计,满足发动机工作的温度要求。

In order to ensure HAN-based green monopropellant thruster working properly,high efficiency thermal design should be implemented that can maintain the temperature of catalyst bed above 200℃,which is higher in comparison with traditional monopropellant thruster.Taking the thruster as the research object,based on the thermal design,the finite element model of the thruster was built,and then the simulation using IDEAS/TMG was performed.In addition,vacuum thermal test was carried out,meanwhile the temperature of some important positions were obtained.It shows that except the temperature of the back part of front catalyst bed,temperature error of other monitoring points between thermal simulation and test are within 4℃,so the simulation results can agree well with test temperature data,the finite element model can be used in temperature prediction on orbit.The front catalyst bed of HAN-based green monopropellant thruster was equipped with a new type of wire heater and then covered with stainless steel foils,joined by hollowed bracket,which can meet the upper and lower limit temperature requirements.