前缘缺口型损伤风扇转子叶栅流动特性分析

Analysis of Flow Characteristics of Fan Rotor Cascade with Leading Edge Notch Damage

为了研究风扇转子叶片在遭遇外物损伤后所造成的叶片型面形变对压气机性能的影响,针对前缘遭遇缺口损伤型的压气机叶型开展数值仿真,分析了其整体气动特性及内部流场细节的变化规律。以某小型大涵道比涡扇发动机风扇转子叶片50%截面叶型为研究对象建立了叶栅模型,假定叶栅中间截面遭遇了球体正向撞击,并在其前缘形成了深度为1.2%相对弦长、宽度为2.5%相对叶高的表面缺陷。借助NUMECA Fine/Open软件包对前缘缺口型损伤风扇转子叶片50%截面叶型平面叶栅进行全通道数值模拟,研究区域共计包含6个叶栅通道,定量分析了损伤前后叶栅的气动特性变化及内部流场结构。结果表明:在来流马赫数为0.6下,前缘缺口型损伤在全攻角范围内增大了叶型总压损失系数,最大相对增大3.11%;扩散因子在前缘损伤后变大,最多增大13.5%。

In order to study the influence of the blade profile deformation on the compressor performance after encountering the foreign object damage on the fan rotor blade,numerical simulation was carried out for the compressor blade with notch damage at the leading edge,the overall aerodynamic characteristics and the variation details of the internal flow field were analyzed.A cascade model was established based on the 50%span airfoil of the fan blade from a small high bypass ratio turbofan engine.It was assumed that the middle section of the cascade was impacted on the leading edge by a spherical particle and a notch damage with a depth of 1.2%chord length and a width of 2.5%blade height was formed at the leading edge.With the help of NUMECA Fine/Open software package,a full-channel linear cascade numerical simulation of the 50%span fan blade airfoil with leading edge notch damage was carried out.The region investigated includes six cascade passages.The changes of aerodynamic characteristics and internal flow field structure of the cascade before and after damage were analyzed quantitatively.The results show that at Mach number 0.6,the leading edge notch damage increases the total pressure loss coefficient of the airfoil across the whole range of angle of attack,with the maximum of 3.11%.The diffusion factor increases up to 13.5%after leading edge damage.