风力机叶片三角襟翼构型及气动特性数值研究

Numerical Study on Configuration and Aerodynamic Characteristics of Triangular Flaps for Wind Turbine Blades

为研究三角襟翼对风力机叶片翼型气动特性的影响,将三角襟翼加至NACA4412翼型尾缘,建立其二维襟翼计算模型,基于CFD数值模拟方法分析不同宽度和长度的三角襟翼在0°~18°攻角范围内的气动特性,得到了各攻角下升阻力系数、升阻比及翼型壁面压强分布曲线。结果表明:增加襟翼长度,使得翼型升阻比减小,失速攻角提前,增加襟翼宽度,使得翼型升阻比增大,失速攻角延后,因此适当减小三角襟翼的长度和增加其宽度有助于提高翼型的气动特性,将翼型尾缘5%部分作为空间生成襟翼,与传统襟翼相比,节省了制造材料和空间。

To study the effect of triangular flaps on the aerodynamic characteristics of wind turbine blade airfoils,the triangular flaps were added to the trailing edge of the NACA4412 airfoil,for which,a two-dimensional flap calculation model was established.Based on CFD numerical simulation,the aerodynamic parameters of the triangular flaps with different widths and lengths were analyzed with the angles of attack in the range of 0°-18°,so as to obtain the lift coefficient,drag coefficient,lift to drag ratio and airfoil wall pressure distribution curve at different angles of attack.Results show that the lift to drag ratio of aerofoil decreases and the stall angle advances with growing length of flap,while the lift to drag ratio of aerofoil increases and the stall angle delays when the width of flap increases,therefore,the aerodynamic characteristics of aerofoil can be improved by reducing the length or increasing the width of flap.Compared with conventional flaps,the manufacturing materials and space are reduced by taking 5% region of aerofoil tail as the space for flap installation.