高亚声速压气机叶片优化设计

Optimization of high subsonic axial compressor blades

为实现压气机叶片的优化设计,采用Hicks Henne函数进行叶型参数化,N S方程流场计算与混合遗传算法结合构成设计软件。以给定叶片表面压力分布为目标,以损失小而扩压度大和给定压比损失最小作为目标,所得优化叶片吸力面等熵马赫数分布合理、符合控制扩散规律,具有较好的压比和损失指标。采用几何方法与椭圆型方程方法结合生成壁面正交H型网格,可提高计算精度和便于采用代数紊流模型的流场计算。

For aerodynamic optimal design of compressor blade, initial blade profile was modified using Hicks-Henne function. The two-dimensional compressor flow field was calculated using Navier-Stokes equation method. A hybrid genetic algorithm was used to search for the optimal blade. When the pressure distribution on blade surfaces was taken as an objective, the corresponding blade profiles can be found effectively. When flow loss is less and pressure rise is large or loss is minimum as pressure rise is given was taken as objective, distributions of isentropic Mach number on the optimal blade suction surfaces are reasonable and consistent with that of controlled diffusion airfoils (CDA). To improve precision of numerical simulation and to apply conveniently algebraic turbulence model, a new kind of H-type grid generation method was proposed, by which the generated grid lines orthogonally intersect at blade surfaces. The grid was generated using geometrical method and then grid lines were smoothed by numerically solving ellipse equations.