风力机叶片21%相对厚度翼型粗糙敏感性研究

基于变速变桨水平轴风力机,依据动量叶素理论和风力机实例,分析得出了叶片外侧翼型(包括21%相对厚度翼型)在低于额定风速变速运行阶段的粗糙敏感性评价指标为升力系数和升阻比的下降率;提出了根据升、阻力系数对输出功率的作用大小来确定两粗糙敏感性评价指标权重系数的方法,并用实例演示了21%相对厚度翼型粗糙敏感性评判基准的获得;另外,通过正交设计、XFOIL软件几何造型与气动计算和方差分析得出了翼型各几何参数在不同雷诺数下对粗糙敏感性不同评价指标的影响程度和最优组合是不一样的。本文结论可为不同风况下风力机翼型的设计和粗糙敏感性评价提供参考。

Investigation on Roughness Sensitivity for 21%Relative Thickness Airfoil of Wind Turbine Blade

The evaluation indicators for roughness sensitivity about the airfoils including 21%relative thickness airfoil at outboard section of the variable-speed and pitch-regulated horizontal axis wind turbine blade during the variable-speed operation below rated wind speed were obtained based on the blade element momentum theory and the data of a real wind turbine,which are the reduction rate of lift coefficient and lift-to-drag ratio.The method to determine the weight coefficient of two evaluation indicators for roughness sensitivity with the impact of lift and drag coefficient on power output was proposed.And the process to get evaluation benchmark of 21%> relative thickness airfoil for roughness sensitivity was shown with an example.In addition,the results obtained through using orthogonal design,geometric modeling and aerodynamic performances calculation with XFOIL,and analysis of variance indicate that the effects of airfoil geometry parameters on the evaluation indicators for roughness sensitivity and their optimal combinations are different at different Reynolds numbers.The conclusions will be helpful for the design and roughness sensitivity evaluation of wind turbine airfoils under different wind regimes.