叶片几何参数对倾斜锯齿尾缘叶片气动及噪声特性的影响研究

Research on the Effect of Blade Geometrical Parameters on the Aerodynamic and Noise Characteristics of Inclined Trailing Edge Serrated Blade

摘要: 本文通过改变叶片相对宽度、相对厚度两个参数，采用数值方法，探究几何参数对倾斜尾缘锯齿叶片的气动及噪声特性的影响。研究结果表明：叶片弯度增大会扩大上下翼面间的压差，并带来显著的增升效果，改善叶片气动性能，而叶片厚度主要是通过影响压力面上的高压区分布来改变叶片气动性的；当来流攻角小于12˚时，增加叶片弯度、减小叶片厚度有利于增升减阻，提高升阻比；大厚度、大弯度叶片表面分离点前移，边界层加厚，层内速度扰动加剧，不稳定流动与叶片壁面相互作用增强，故叶片绕流过程中的辐射噪声相应增大。

Abstract: In this paper, by changing the relative width and relative thickness of the blade, numerical methods are used to explore the influence of geometric parameters on the aerodynamic and noise characteristics of the inclined trailing edge serrated blade. The research results show that the in-crease of the blade camber will enlarge the pressure difference between the upper and lower airfoil surfaces, bring about a significant increase in lift effect, and improve the aerodynamic performance of the blade, and the blade thickness mainly changes the aerodynamic performance of the blade by affecting the distribution of the high pressure area on the pressure surface. When the angle of attack of the incoming flow is less than 12˚, increasing the blade camber and reducing the blade thickness are beneficial to increase lift, reduce drag, and improve the lift-drag ratio; the surface separation point of the blade with large thickness and large curvature moves forward, the boundary layer is thickened, the internal velocity disturbance intensifies, and the interaction between the unstable flow and the blade wall is enhanced, so the radiation noise during the flow around the blade increases accordingly.