C/C扩张段典型连接结构热应力对比分析及试验研究

C/C扩张段与喷管基础段的连接结构是影响C/C扩张段热应力的关键因素,为了获得最优连接形式,采用相同的边界条件、材料参数和结构尺寸,对螺纹、倒锥、销钉和套锥共4种典型连接结构的C/C扩张段进行了热应力数值模拟。通过温度场和应力场对比分析,并考虑工程应用性,认为销钉连接结构最优。采用φ340 mm试验发动机,对销钉连接结构C/C扩张段开展了热试车考核。试车后,C/C扩张段结构完整,验证了该连接结构的设计合理性。热试车过程中,成功测试了C/C扩张段外壁面的实时温升曲线,各测点的温升规律以及沿轴向的温度趋势与理论分析基本一致,发动机工作结束时最高温度达1 127℃。

Comparative analysis of thermal stress and test research for C/C divergent section with typical connecting structure

Connecting structure is a key factor influencing the thermal stress of C/C divergent section,so the thermal stress of C/C divergent section with thread,barb,pin and taper sleeve four typical connecting structures was calculated in the same boundary conditions,material properties and dimension to get the best connecting structure. The pin connecting structure is recognized as the best one by comparing the temperature field,stress field and engineering application.Then the pin connecting structure was checked under firing by using ?340 mm testing engine.The C/C divergent section structure was integrated after firing test,which validated the design rationality of this structure. The outer wall temperature curves of C/C divergent section were provided by firing test. The results show that temperature regulation and axial temperature variation tendency are almost consistent with theory analysis, and the maximum temperature of 1127 ℃ occurs at the end of firing test.