Design Optimization of the Convergent Passage Profile of a High-Load Turbine Vane Endwall

Due to the application of low-NOx combustion technology, the protection of blade endwall from the hot gas has been essential for the advanced gas turbines. The reasonable design of endwall profile can not only improve the thermal efficiency of the cascade, but also reduce the heat load on the endwall. In this paper, a high-load vane endwall is taken as the research object, and the convergent passage profile of the endwall is optimized. The optimization design variables are locations of control points of the endwall shape. And the optimization objective functions are the total pressure loss coefficient of the cascade passage and the heat load on the endwall. The multi-objective genetic algorithm coupled with surrogate model is adopted. After the optimization, heat load of the endwall and total pressure loss of the cascade are reduced relative to the original design.