双脉冲发动机中金属膜片动态与静态打开对比分析

Research on Dynamic and Static Opening of Metal Diaphragm

关键词:  双脉冲发动机  金属膜片  动态打开  静态打开

Key words:  Double pulse motor  Metal diaphragm  Static opening  Dynamic opening

摘要:

为了研究双脉冲发动机中金属膜片的打开特性，分别选取Ductile damage模型和Brittle cracking模型来模拟膜片静态和动态打开过程。数值计算发现膜片分别在3.46MPa静态内压载荷和1.95MPa动态内压载荷作用下打开。为了验证计算结果的有效性，进行了膜片的冷流静态打开和热流动态打开试验，膜片分别在平均3.75MPa静态载荷和平均2.2MPa动态载荷作用下打开，数值计算结果与试验结果一致，说明了数值计算方法的有效性。计算结果和试验结果表明，膜片的静态打开压强明显高于动态打开压强，分析认为是由于膜片的塑性变形、材料本身特性及预制缺陷处的应力松弛引起的。根据隔舱的冷流及热流单项试验可以发现，膜片的打开形式与预期一致，满足双脉冲发动机的使用要求。

Abstract:

In order to study the opening property of metal diaphragm in double pulse solid rocket motor，ductile damage model and brittle cracking model were used to simulate the dynamic and static opening process. The simulation static opening pressure was 3.46 MPa and the simulation dynamic opening pressure was 1.95 MPa. To further verify the accuracy of simulation，the verification tests were carried out. The real average static opening pressure was 3.75 MPa and the real average dynamic opening pressure was 2.2 MPa. The computational results agree with the tests results well. The numerical method in this article is effective. The static opening pressure is obviously higher than the dynamic opening pressure，which is considered to be due to the plastic deformation of the diaphragm，the material itself characteristics and stress relaxation of prefabricated defect. It can be found that opening mode of metal diaphragm is in line with expectations in the cold and heat tests，which can satisfy with the design requirements.