固体火箭发动机药柱低温损伤研究进展

Research progress on low temperature damage of SRM grain

从细观损伤、宏观损伤、损伤模型三方面,对固体火箭发动机药柱低温损伤的研究进展进行了综述,并对下一步的研究方向和重点提出建议。目前,用于宏细观损伤分析的固体推进剂本构模型考虑了温度和应变率的影响,但在引入围压条件后,推进剂的力学性能发生显著变化,其抗拉强度、断裂强度和初始模量有显著提升,而最大伸长率则显著降低,考虑围压因素的本构模型研究未来将成为重点;固体火箭发动机低温点火升压的多载荷条件下损伤产生和演化过程已有很多的研究,但对“脱湿”损伤、基体损伤和颗粒断裂损伤发生的时机和机理尚为形成统一理论;损伤模型大多是基于试验结果的唯象模型,未来可借助新的试验设备设计新的试验方法,对细观尺度的损伤进行研究,从而建立基于细观结构的损伤模型。

The current situation about the damage of solid propellents at low temperature is summarized and the important point and direction from the in the field of this study are expected from the aspect of meso damage,macro damage and damage model.The constitutive model of solid propellant currently used in macro and meso damage analysis considers the effects of temperature and strain rate.However,the mechanical properties of the propellant change significantly after the ambient pressure is introduced,and its tensile strength,fracture strength and intial modulus has been significantly increased,while the maximum elongation has been significantly reduced.Research on constative models that consider the ambient pressure factors will become the focus in the future.There have been many studies in the damage generation and evolution process of solid rocket motors under the multi-load condition of low-temperature,ignition and boost pressure.However,the timing and mechanism of“dewetting”damage,matrix damage and particle fracture damage have not yet formed a unified theory.Most of the damage models are based on the phenomenological model of the test results,in the future,new test equipment can be used to design new test methods to study the damage of the meso-scale,so as to establish a damage model based on the meso-structure.