基于离散伴随方法的透平叶栅气动优化设计

本文研究并给出了基于离散伴随理论和自动微分技术构建离散伴随系统的方法、伴随系统的求解策略以及基于离散伴随方法的透平叶栅气动优化设计流程,建立了相应的优化设计系统。利用该优化系统在无黏环境下,以叶栅通道进出口的熵增率为目标函数、以叶栅通道内的质量流量为约束,对某二维跨音速透平叶栅进行了气动优化设计。与优化前相比,优化后透平叶栅进出口熵增率减少8.82%,质量流量变化幅度小于0.003%。优化结果表明,本文提出的优化系统能够有效改善透平叶栅的气动优化性能,验证了本文提出的基于离散伴随方法的透平叶栅气动优化设计方法的正确性与有效性。

Aerodynamic Optimization Design of Turbomachinery Cascade Based on Discrete Adjoint Method

The method of the discrete adjoint system,based on the discrete adjoint theory and automatic differentiation technology,was studied and proposed in this paper.Moreover,the solution strategy and the optimization flow chart based on the discrete adjoint method were also set up. Based on the theory,an aerodynamic optimization design system for the turbine cascade was established.Based on the optimization system,a typical 2D transonic turbomachinery cascade was optimized under the inviscid flow environment at a fixed operation condition.The minimization of the entropy generation rate was taken as the objective function in the design optimization process and a mass flow rate constrain was added.According to the optimization result,the cascade entropic generation ratio was reduced by 8.82%,while the mass flow ratio through the final cascade passage was only increased by 0.003%as compared with that of the initial cascade.The optimization results indicate the present optimization system could effectively improve the aerodynamic performance of turbomachinery cascades.The validity and efficiency of the optimization design system were proved.