考虑初始界面缺陷的复合固体推进剂力学性能研究

Research on Mechanics Properties of Composite Solid Propellants Considering Initial Interface Defects

为研究复合固体推进剂初始缺陷对其宏观力学性能的影响,通过单轴等速拉伸实验得到了不同界面缺陷含量推进剂的工程应力-应变曲线。比较发现,推进剂的初始模量和拉伸强度随缺陷含量的增高呈指数下降的趋势。构建了含界面缺陷推进剂的细观模型,定义了缺陷界面的力学响应,数值模拟了推进剂在单轴拉伸载荷下的力学响应。将仿真结果与实验结果进行对比,二者变化趋势一致,误差范围在7.5%之内,说明文中所用方法能为含缺陷的复合固体推进剂的研究提供指导。

In order to study the effects of the initial defects of composite solid propellant on the macroscopical mechanical properties, the engineering stress-strain curves of the propellants with different interface defect content were obtained through the uniaxial constant speed tensile test. It was found that the initial modulus and the tensile strength of propellants tended to decrease exponentially with the increase of the defect content. Then a mesoscopic model of propellant with interface defects was built and the mechanical response of defect interface was defined, and the mechanical response of propellants under the condition of uniaxial tensile load was simulated. Finally, comparing the simulation results with the experimental results, it is showed that the variation trend of the two is the same, and the error range is within 7.5%, which means that the method in this paper has some guidance values for the research of composite solid propellants with defects.