Sub-model decomposition-based collaborative optimization method for multi-region film-cooling holes in turbine blades

This study proposes a collaborative optimization method based on sub-model decomposition to address the challenges of numerous design parameters, high computational cost, long calculation times, and scale insensitivity in the optimization of turbine blade film-cooling hole structures. The method first establishes sub-models for structures in critical regions based on the global finite element model of the turbine blade. Surrogate models for the structural responses of the film-cooling holes are then constructed and optimized within each sub-model. The process iterates until collaborative optimization across all sub-models is completed through one or multiple rounds. After obtaining the optimized solutions of all sub-models, the overall model of the turbine blade is updated to determine whether the stress value of the overall model meets the requirements. If not, the sub-model division, solution, and optimization are required again until the stress value of the overall blade meets certain requirements, thus completing the coordinated optimization of the sub-model and the overall blade. Compared with the overall blade structure optimization method, the optimization results of the proposed method improve the optimization efficiency by 57.38%. The stress value in the dangerous area of the film-cooling holes decreases by 22.5%. The proposed optimization method is effective and has great application value in the optimization of the film-cooling hole structure of turbine blades.