双脉冲固体发动机隔板预紧载荷数值分析

Numerical analysis on port cover of dual-pulse solid rocket motor under preload

针对装配预紧力载荷容易导致双脉冲固体火箭发动机陶瓷隔板破坏的问题,利用ANSYS软件建立了陶瓷隔板组件的平面轴对称有限元模型,分析了陶瓷隔板与其支撑紧固件之间的相互作用。认为陶瓷隔板与紧固件之间接触压力引起的翘曲变形是引起破坏的直接因素,发现等厚度设计形式的陶瓷隔板对预紧载荷的承受能力不足,难以保证其安全装配。计算分析了各结构设计参数对提高陶瓷隔板预紧载荷承受能力的影响,发现修改紧固件结构成效不理想,较合理的方法是优化陶瓷隔板的设计形式,提高其预紧力载荷承载能力的同时兼顾较好的易碎性。

The ceramic port cover（CPC）on a dual-pulse solid rocket motor under preload is easy to structurally fail during experiment assembly operation.Aiming to solve this problem,a planar axisymmetric finite element model in ANSYS software was conducted to analyze the mechanical interaction between the CPC and its fixture parts.The warping deformation is the direct origin of the structure fail,which is caused by the contact pressure between the CPC and its fixture parts.The tolerance ability under preload of CPC with an iso-thickness design is not enough to guarantee a safe assembly operation during experiments.The effects of several structure factors on the preload capacity of CPC were analyzed.According to the calculation result,the effect of modifying the fixture parts structure design of CPC to enhance the preload capacity is not perfect.Optimizing the structure design of the CPC itself and enhancing the weakness spot on the CPC should be a better way,in the meanwhile the fracture performance of CPC should also kept.