下游塔架对水平轴风力机叶片气动负荷的作用

Effect of downstream tower on aerodynamic load of horizontal axis wind turbine blades

为了研究水平轴风力机叶轮与下游塔架之间的动静干涉作用,并将二者的相互作用简化为二维翼型与后置圆柱之间的气动干涉,通过数值模拟的方法分析了在翼型尾缘下游不同位置处放置的圆柱对叶片载荷的影响.研究结果表明,下游塔架对叶片载荷的影响主要与塔架直径和二者的相对位置有关.当叶片掠过圆柱塔架时,翼型上下表面的流速分布产生了明显的改变,进而造成气动载荷发生显著的变化,其变化幅度可以达到定常计算情况下的50%.该工作对风力机叶片的周期气动力疲劳寿命的评估提供了参考.

To study the stator-rotor effect between the horizontal axis wind turbine rotor and its downstream tower, this paper proposed a simple flow model of two-dimensional airfoil and downstream cylinder to simulate their aerodynamic interaction. Numerical study reveals the influences from downstream cylinder at different locations on the blade aero-loads. Results show that the effect comes mainly from the relative position between tower and rotor in comparison to tower diameter. When rotor sweeps over cylinder tower, the flow＇s velocity distribution is apparently changed along airfoil＇s upper and lower surfaces. Blade loading and airfoil lifting factor are then altered with evident values, which may be accounted for 50 % of those in steady running conditions. The method presented herein may be refered to evaluate HAWT blade fatigue life under aerodynamic load in running conditions.