CMC S弯喷管材料-结构多尺度优化设计研究

Serpentine nozzle，which is a large-sized thin-walled structure，displays complex overall and local stiffness characteristics due to the influence of multiple-field coupling effects. This study proposes a continuous rib-reinforced structure for serpentine nozzle using ceramic matrix composites（CMC）to effectively mitigate overall and local deformations. In comparison to GH4169，CMC demonstrates a 45.31% reduction in nozzle deformation while simultaneously reducing mass by 62.77%. Additionally，the rib-reinforced structure presented in this paper can further decrease CMC serpentine nozzle deformation for 43.15%. To minimize the mass of CMC rib-reinforced serpentine nozzle，a material-structure multiscale optimization is conducted using surrogate models and the differential evolution algorithm. The optimization variables encompass the warp/weft yarn ratio in the microstructure of CMC，as well as the partition wall thickness and rib size in the macrostructure of the nozzle. Through this optimization process，a mass reduction of 26.21% is achieved while maintaining the same stiffness requirements.