为提高某型燃气轮机的工作可靠性，对单晶涡轮叶片进行了强度分析与结构优化设计。采用第四强度理论，考虑了晶体取向、温度载荷、气动载荷和转速的影响，得到叶片的应力分布、典型截面的强度储备系数；根据诺顿蠕变方程计算关键节点的持久寿命；基于分析结果对叶片局部结构进行优化改进，将叶片质心向叶背侧偏移，调整进气前缘气膜孔的排列方式，并对新结构进行强度复算。结果表明：优化后的叶片静强度符合设计要求，消除了局部结构处的应力集中现象，叶身结构强度储备系数高于1.3，叶身两侧应力分布更加均匀，叶片在设计转速10%裕度范围内无共振现象发生。

In order to improve the working reliability of a certain type of gas turbine, the strength analysis and structural optimization design of single crystal turbine blades were carried out. By using the fourth strength theory, the influences of crystal orientation, temperature load, aerodynamic load and rotational speed were considered, and the stress distribution and strength reserve coefficient of typical section of blade were obtained; the lifetime of key nodes was calculated according to NORTON creep equation; based on the analysis results, the local structure of the blade was optimized and improved. The centroid of the blade was shifted to the back side of the blade, the arrangement of the air film holes at the inlet front was adjusted, and the strength of the new structure was calculated doubly. The results show that the optimized static strength of the blade meets the design requirements, the stress concentration in the local structure is eliminated, the strength reserve coefficient of the blade structure is higher than 1.3, the stress distribution on both sides of the blade is more uniform, and the blade has no resonance phenomenon within the design speed margin of 10%.

TK221

国家科技重大专项（J2019Ⅲ00120055）