热-机械载荷下厚壁圆筒自增强压力优化分析

摘要

The optimum autofrettage pressure of thick - walled cylinders under thermo - mechanical loadings was analyzed. The theoretical solutions were compared with those numerical results obtained by the optimization analysis based on ANSYS. The results indicated that the analytic solutions of the optimum autofrettage pressure are in good agreement with the numerical solutions and the maximum error is less than 1 % . Moreover, without considering the effect of thermal load, autofrettage may increase the difference of the equivalent stress between the inner and outer wall, which decreases the fatigue strength of thick cylinders. The analytic solution of the optimum autofrettage pressure can be used for engineering designs to improve the load - carrying capacity of thick cylinders.%理论上推导了厚壁圆筒在内压及热载荷共同作用下的最佳自增强压力,并基于ANSYS的优化分析结果对理论解进行了验证.结果表明最佳自增强压力的理论解与数值解一致,最大误差不 超过1％；另外,不考虑热载荷进行自增强后,会增大工作状态下厚壁圆筒内外壁应力差,降低结构的疲劳强度；工程上可根据本文解析解进行自增强处理,以提高厚壁圆筒的承载能力.