基于多精度代理模型的高效异型气膜孔设计优化和实验验证

为了提升燃气轮机热端部件表面的气膜冷却效果,本文发展了一套基于多精度代理模型的高效气膜孔优化方法,通过对气膜孔孔型进行优化得到最优的气膜冷却效率。与传统的代理模型优化方法相比,本文构建的多精度代理模型优化方法能有效结合实验数据与高精度数值计算,在保证准确度的同时使优化效率提升64.5%。本文针对业界广泛使用的一种气膜孔进行优化设计,选取后倾角、侧扩角和孔长径比作为三个设计变量,采用遗传算法和序列二次规划混合方法进行优化。并采用3D打印和PSP测量技术对优化孔型进行验证,发现和初始孔型相比优化孔型的面平均气膜冷却效率提升39%。本文的工作证明了多精度代理模型在气膜冷却优化方面的有效性。

Multi-fidelity Based Optimization of Shaped Film Cooling Hole With Experimental Validation

An optimization framework is developed for the film cooling hole shape design to achieve highest film cooling effectiveness with affordable cost.Compared with single-fidelity surrogate model,multi-fidelity model developed in this work combines vast existing knowledge about shaped film cooling hole and three-dimensional numerical simulation.As a result,the computation cost has been substantially decreased by 64.5% while accuracy is maintained with similar level,which provides a firm basis for the optimization.Considering three geometric parameters as design variables,i.e.laidback angel,lateral angle,and hole length-diameter ratio,the shaped hole is optimized with genetic algorithm(GA)combined with sequential quadratic programming(SQP) algorithm.After the optimization,an experiment campaign is further carried out to validate the optimization result using pressure sensitive paint(PSP) technology.With current multi-fidelity model,the spatially averaged film cooling effectiveness has been improved by 39% compared with the baseline.This work verifies the effectiveness of current multi-fidelity model for the design and optimization of shaped film cooling hole for better performance.