翼型高低速性能优化及其对缝翼设计影响研究

Concurrent optimization of airfoil high/low performance and its impact on slat design

采用Hicks-Henne方法参数化翼型,以巡航升阻比、低速最大升力系数为目标进行优化设计。利用试验设计方法对总体设计空间内目标函数的分布进行初步评估,得到目标函数的初始Pareto前沿面,以前沿面上的点为基准,把总体设计空间分割成独立的局部设计空间进行并行寻优,逐步更新直至得到收敛的Pareto前沿面。对前沿面上的典型翼型进行了缝翼设计优化,结果表明:在给定缝翼偏角下,两段翼型在主翼上表面分离点位于65%弦长处时获得最大升力系数;巡航阻力小的翼型更容易获得较好的增升效果;在某一缝道参数下,Pareto前沿面上各翼型的两段翼型都处于最佳状态。

Hicks-Henne method was used to parameterize a supercritical airfoil,and cruise lift drag ratio（L/D） and low speed maximum lift coefficient were used as objectives to be optimized.A primary Pareto front was obtained by using Design of Experiment（DOE） method to give an estimation of objective distribution in the design space.Based on samples on the Pareto front,the global design space was divided into relatively small local design spaces to search the optimum points in parallel to achieve a converged Pareto front.Slats were designed and optimized for sample points on the Pareto front to study links between low speed maximum lift coefficient and cruise L/D.The result shows that： the airfoil will reach its maximum lift coefficient when the separation point on upper surface is located at 65% chord length;it is relatively easier to design a more efficient high-lift device for airfoil with a higher cruise L/D;there exists a combination of gap and overlap to make all airfoils perform relatively more efficient.