On Local Geometry-Based Source-Term Method and Optimization for Effusion Cooling in a Swirling Flow

Effusion cooling provides high cooling effectiveness with low coolant consumption, making it highly suitable for the thermal protection of gas turbine combustor liners. However, combustor liners typically feature a large number of cooling holes, leading to complex geometries, intricate mesh generation, and substantial computational loads. To address this issue, the local geometry-based source term method has been developed, which eliminates the necessity to explicitly generate meshes for cooling holes, thereby simplifying the computational process. The local geometry-based source term method is first applied to simulate the effusion cooling of a flat plate to verify its accuracy, with simulation results exhibiting good agreement with experimental measurements. It is subsequently extended to simulate the full-coverage multiperforated plate in a swirling flow, examining its applicability under varying blowing ratios and swirl numbers. Furthermore, a multi-objective optimization framework is developed to optimize the hole diameters in different regions, achieving a 20.3% reduction in the maximum temperature rise of the combustor liner at equal coolant consumption or a 15.3% reduction in coolant consumption while maintaining the same maximum wall temperature. The local geometry-based source term method offers the potential to both eliminate the need for mesh generation of a great number of cooling holes and achieve the desired prediction accuracy, making it well suited for the design optimization of effusion cooling systems.