固体火箭发动机装药粘接界面Ⅰ-Ⅱ混合型内聚力模型反演研究

Inversion of I-II Mixed Cohesive Zone Model for Solid Rocket Motor Charge Bonding Interface

针对以人工试算的方式获取粘接界面所采用的张开型-剪切型(Ⅰ-Ⅱ)混合型内聚力模型存在精度低且工作量大等问题,采用分步反演与Hooke-Jeeves优化算法相结合的识别方法,基于矩形粘接试件多角度拉伸载荷-位移实测数据,对装药粘接界面所采用的Ⅰ-Ⅱ混合型内聚力模型开展反演研究。反演结果表明:拉伸速率为5mm/min时,界面刚度、最大名义应变、临界断裂能的法向值分别为0.17MPa,3.85,6.14kJ/m^(2),切向值分别为0.09MPa,1.66,2.66kJ/m^(2);0°,22.5°,45°拉伸的仿真与实测载荷-位移曲线的相对误差分别为7.2%,5.1%,5.2%;基于反演获取的Ⅰ-Ⅱ混合型内聚力模型的界面损伤系数分布图定量分析粘接界面的破坏情况,与实验结果吻合良好。以上均表明所采用的反演方法可有效修正粘接界面Ⅰ-Ⅱ混合型内聚力模型的相关参数。

Aiming at the problem that the Ⅰ-Ⅱ mixed cohesive zone model used to obtain the bonding inter-face by manual trial calculation has some drawbacks,such as low accuracy and heavy workload,the identifica-tion method is a combination of stepwise inversion and Hooke-Jeeves optimization algorithm.Based on the mea-sured data of multi-angle tensile load-displacement of rectangular bonded specimens,inversion of Ⅰ-Ⅱ mixed co-hesive zone model used in charge bonding interface was studied.The inversion results show that the normal values of interface stiffness,maximum nominal strain and critical fracture energy are 0.17MPa,3.85 and 6.14kJ/m^(2),the tangential values are 0.09MPa,1.66 and 2.66kJ/m^(2),respectively,when the tensile rate is 5mm/min.For the ten-sile angles are 0°,22.5°and 45°,the relative errors of simulation and measured load-displacement curves are 7.2%,5.1%and 5.2%,respectively.The interfacial damage coefficient distribution based on the Ⅰ-Ⅱ mixed cohe­sive zone model obtained by inversion method can quantitatively describe the failure of the bonding interface,which is consistent with the experimental results.The adopted inversion method can modify the Ⅰ-Ⅱ mixed cohe-sive zone model parameters effectively.