Low cost optimization of gas turbine endwall film cooling based on geometric prior knowledge

Discrete-hole film cooling is a core technology for gas turbine endwall cooling. Hole arrangement optimization is one of the important directions to improve the endwall cooling performance. The main challenge in endwall film cooling design is the priori definition of hole arrangements. Existing methods, such as row-based, partitioned, and isoline arrangements, are limited by their simplistic geometric constraints, which do not match the local physical conditions of the endwall, leaving considerable room for improvement in cooling performance. The study presents a priori definition mode of hole arrangements that applicable to endwall film cooling design tasks, and develop a low-cost and high-performance optimization method for endwall film cooling hole arrangements. Finally, the proposed optimization method based on geometric prior knowledge was applied to optimize endwall film cooling hole arrangements for the GE E3 turbine firststage stator. Compared to isotherm-based arrangements, the geometric prior knowledge optimized arrangements improved cooling in the inlet wedge region and the pressure side corner region. The results demonstrated the low cost and high performance of the proposed geometric prior knowledge.