轴流压气机跨音叶型前缘优化设计

Research on the optimization of the leading edgefor transonic airfoil of axial flow compressors

叶型前缘的几何外形直接影响轴流压气机的综合气动性能,为了研究前缘椭圆度的最佳区间变化规律,对跨音叶型Stator35叶中截面进行了优化设计。基于参数化方法和元启发式算法建立了叶型前缘椭圆度的寻优模型,探讨了圆形和椭圆形前缘叶型的气动性能,对比分析了多种椭圆度前缘叶型的流场结构,并对椭圆前缘三维叶片的几何外形进行了气动寻优。结果表明:椭圆度前缘叶型在全工况范围内降低了总压损失系数,拓宽了3°攻角,提升了落后角和折转角性能;跨音叶型椭圆前缘设计存在最佳椭圆度区间[0.8,0.9],并且转捩点位置距前缘距离与分离泡长度负相关;优化后设计点处椭圆前缘叶片的绝热效率提高了0.4%,且在全流量范围内绝热效率均高于原始叶片,喘振裕度从9.8%提升到12.4%。

The geometry of the leading edge of the blade shape directly affects the overall aerodynamic performance of an axial flow compressor.In order to investigate the optimal interval variation of the leading edge ellipticity,this paper optimizes the design of the mid-section of transonic airfoil Stator35.Based on a parametric method and a meta-heuristic algorithm,an optimization-seeking model of the leading edge ellipticity of the blade is established,and the aerodynamic performance of the circular and elliptical leading edge blades is discussed.The flow field structures of a variety of elliptical leading edge blades are compared and analyzed,and the aerodynamic optimization of the three-dimensional elliptical leading edge blades is carried out.The results show that,under a full range of operating conditions,the elliptical leading edge blades reduce the total pressure loss coefficient,widen the 3°angle of attack and improve the performance of trailing and turning angles.It is clarified that there is an optimal ellipticity interval[0.8,0.9]for the elliptical leading edge design of transonic airfoil,and the distance between the turning point and the leading edge is negatively correlated to the separation bubble length.After optimization,the adiabatic efficiency of the elliptical leading edge blades at the design point increases by 0.4%,which is higher than the original blades in the full flow range,and the surge margin increases from 9.8%to 12.4%.