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

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.