上游小圆柱对翼型气动性能的影响研究

Study on the Effect of Upstream Small Cylinder on the Aerodynamic Performance of Airfoil

采用数值模拟研究了一种适用于垂直轴风力机流动控制的被动控制方法--上游小圆柱。小圆柱安装在NACA0018翼型前缘的正前端,通过改变圆柱直径和圆柱与翼型前缘距离分析了不同参数下圆柱对Re=2×10^6时翼型的气动性能的影响。结果表明,当小圆柱置于合适位置,可以有效延迟失速(最大延迟达8°),提升大攻角下的翼型升力系数和切向力系数以及减小大攻角下的翼型阻力系数。此外,相对大直径的小圆柱可以起到更好的控制效果,并在更宽的间距范围起作用。

A passive flow control method,namely upstream small cylinder,was numerically investigated for vertical axis wind turbine.The small cylinder was installed in the front of the leading edge of the NACA 0018 airfoil.The effect of the cylinder on aerodynamic performance of the airfoil was studied by changing the diameter of the cylinder and the distance between the cylinder and the leading edge of the airfoil at Re=2×10^6.The results showed that when the cylinder was placed in proper positions,the stall angle was effectively delayed(with maximum delay angle of 8°),the lift and tangential force coefficients were increased and the drag coefficients were reduced at large angles of attack.In addition,the cylinder with a relatively large diameter showed better control effect over a wider range of the distance.