后掠式叶片气动外形优化设计

Aerodynamic Shape Optimization Design of Backward Swept Blade

后掠式叶片具有载荷自适应性,提出了一种以自然样条曲线为后掠曲线,以扭角为优化参数的后掠式叶片优化设计方法。以直叶片模型为设计起点,通过Profili软件获得叶片的截面数据并计算叶片翼型在不同攻角下的升力系数与阻力系数,以叶片功率系数最大以及叶片根部载荷最小为优化目标,采用遗传算法对叶片进行优化设计。根据优化结果获得的参数,建立后掠式叶片三维模型,在ANSYS Workbench中建立流场模型进行仿真分析得到叶片模型的压力分布情况。结果表明,通过对扭角、后掠值进行优化,后掠叶片模型对比直叶片模型其受到的载荷有所减小,优化设计方法可以用于指导后掠叶片的设计。

A backward swept blade has load adaptability.To study design method of backward swept blade,we present a design method of backward sweep blade and it takes a natural spline curve as the backward swept curve and sets torsion angle as the optimal parameter.The optimization design is on the basis of a straight blade.The section data of blade are obtained by the software Profili,and then we calculate lift coefficients and drag coefficients of airfoil at different angles.We take the maximum power coefficient of the blade and the minimum load at the root of the blade as the optimization objectives.The parameters of blade are optimized by genetic algorithm.According to the parameters obtained from the optimization result,a 3d model of swept blade is established.We establish a flow field model in ANSYS Workbench to simulate pressure distribution of two blade models.The simulation results show that by optimization of torsion angle and swept value,the load of the blade model is reduced compared with that of the straight blade model.The design method can be used to guide the design of backward swept blade.