Multi-Objective Optimization of Multi-Channel Cooling Flow Distribution for Turbine Vanes Under Constant Total Cooling Air Flow

The cooling performance of turbine vanes with thermal barrier coatings (TBCs) is significantly affected by the flow distribution of internal cooling channels. To investigate the influence of channel flow distribution on the vane cooling characteristics, this study adopts the Latin hypercube sampling method to realize differentiated flow distribution of each cooling channel under a nearly constant total cooling flow rate. Numerical simulations are performed to obtain vane cooling characteristic data under various flow distribution schemes, followed by multi-condition quantitative comparison and mechanism analysis. The results show that the trailing edge channel serves as the dominant factor controlling the overall vane temperature, while the middle channels exhibit obvious cooling redundancy. Specifically, the flow rates of the leading edge arc and trailing edge dominate the peak temperature and average temperature of the suction surface, respectively. Unlike geometric optimization that alters vane internal structures, this study focuses on flow redistribution under the strict constraint of fixed total cooling air consumption. This strategy offers a zero-cost approach to cooling enhancement for in-service turbines with no structural modifications required. The cooling benefit is enhanced without additional cooling air consumption. The overall surface peak temperature is reduced by 0.4%. By region, the peak temperatures of the pressure surface and the suction surface reduced by 0.40% and 0.435% respectively, and the leading edge arc reduced by 0.20%. The overall average surface temperature has reduced by 0.117%. The research conclusions can provide a theoretical reference for the flow optimization of turbine vane cooling channels and the improvement of overall cooling uniformity, which is qualitatively beneficial to reducing the thermal failure risk of coatings.