Abstract: The randomness of parameters must be accounted for in structural analysis of solid rocket motor grain. Basing on perturbation method and incremental FEM suitable for incompressible materials, a new type of viscoelastic stochastic finite element method is investigated. The local averaging method is used to discretize the random field. The influence of random relaxation modulus is discussed. Numerical results reveal that the proposed approaches have the advantages of the simple and convenient program implementation, and are accurate and effective for the structural analysis of solid rocket motor grain with random relaxation modulus.

Key words: Solid propellant;Propellant grain;Viscoelasticity;Finite element method;Random variable;Elastic modulus;Structural analysis

摘要： 为了研究性能参数的分布对药柱结构完整性的影响 ,以不可压缩粘弹增量有限元和摄动法为基础 ,采用局部平均方法对随机场进行离散 ,发展了一种松弛模量随机粘弹有限元方法 ,讨论了模量的随机性对结构分析的影响。对药柱进行随机模拟 ,程序实施简单 ,计算效率和精度较高。

关键词: 固体推进剂;推进剂药柱;粘弹性;有限元法;随机变量;弹性模量;结构分析