一种固体推进剂药柱结构完整性的快速评估方法

摘要

To realize the rapid assessment of the structural integrity of solid propellant grain,starting with the dynamic modulus of propellant grain,a fast real-time assessment method for the equivalent modulus of solid propellant grain un-der dynamic load condition is established.Then,the concepts of temperature strain coefficient and pressure strain coef-ficient are put forward,a calculation model of the equivalent strain and equivalent stress of grain under dynamic load condition is set up,and the change of equivalent strain and equivalent stress of the dangerous position of grain at all times can be obtained,and the results are compared with finite element simulation ones based on linear viscoelasticity theory.The results show that the maximum difference between the equivalent strain and the equivalent stress of the dangerous position of grain under three kinds of curing cooling curves obtained by two calculation methods are 4.60%and 4.74%,respectively and the maximum difference between the equivalent strain and the equivalent stress of the dangerous position of grain obtained by two calculation methods under ignition pressurization curves are 1.93% and 1. 23%,respectively and the time required for the assessment method is greatly reduced,so the assessment method can be used for rapid assessment of structural integrity analysis of solid propellant grain.%为了实现固体推进剂药柱结构完整性的快速评估,首先从推进药柱的动态模量入手,建立了一种动态载荷作用下药柱等效模量快速实时评估方法;然后提出了温度应变系数和压力应变系数的概念,建立了动态载荷工况下药柱等效应变和等效应力的计算模型,可得到药柱内部危险位置在各个时刻的等效应变、等效应力的变化情况;并与基于线黏弹性理论的有限元模拟计算结果进行了对比.结果表明,两种计算方法得到的3种固化降温曲线下,药柱危险位置的等效应变和等效应力的最大差值分别为4.60%、4.74%;3种点火增压曲线下药柱危险位置的等效应变和等效应力的最大差值分别为1.93% 和1.23%;且该评估方法计算所需时间大大减少,可用于固体推进剂药柱结构完整性的快速评估.