温度循环条件下固体装药应力及累积损伤研究

为考察外界环境对固体火箭发动机的影响,基于热粘弹性模型,利用有限元方法对其装药进行了温度循环条件下的顺序热应力耦合模拟,给出了温度场和应力场,建立了基于应力的累积损伤模型,研究了其累积损伤及主要影响因素。结果表明,温度循环条件下,装药内部产生交变应力,导致损伤累积。温度转换期间累积损伤增长较快,特别是在高温向低温转换期间,影响最大,并且随着升降温速率的增加,累积损伤显著增加。这为准确评估外界环境对固体火箭发动机的影响提供了参考。

Stress and Cumulative Damage of Solid Charge Under Temperature Cycling Condition

In order to evaluate the effect of environment on solid rocket motor,the stress and temperature field of propellant charge under temperature cycling conditions were computed by finite element method considering thermo-viscoelasticity of propellant charge.The cumulative damage model was built based on stress of solid rocket motor and its effects were also studied.The results indicate that,cycling stress and damage were cumulated inside charge with temperature cycling.In one cycle,the cumulative damage increases quickly over courage of temperature transferring,especially from high temperature to low temperature.And the cumulative damage increased distinctly with increasing of the temperature’s warming or cooling rate.This can offer reference in evaluating the effect of environment on solid rocket motor.