预弯外形对风力机叶片气弹稳定性的影响

INFLUENCE OF PRE-BEND SHAPE ON AEROELASTIC PERFORMANCE OF WIND TURBINE BLADES

为了研究预弯外形对风力机气弹稳定性的影响,以某2 MW低风速风电叶片为研究对象,采用外形参数化表达方法构造叶尖预弯量分别为3、4和5 m的叶片。基于SIMPACK软件建立并验证气-弹-控耦合的风力机整机模型,对配装不同预弯叶片的风力机进行仿真分析。结果显示,在湍流风况下,随着叶尖预弯量的增大,叶根载荷、叶尖附近截面的气弹变形量和动态失速程度都有明显增加;对预弯5 m叶片的动态气弹变形进行频域分析,发现在一阶摆振和扭转方向发生共振现象,表明过大的叶尖预弯设计量会使叶片产生气弹失稳问题。

In order to study the effect of the pre-bend shape on the aeroelastic stability of wind turbines,by using the parametric modeling method,three blades with different pre-curved shape were constructed.Based on SIMPACK software,the multi-disciplinary model of wind turbines coupling of aerodynamics-elasticity-control was built.As a research object,the performances of a 2 MW wind turbine with different pre-bend blades were studied,the result shows that under turbulent wind conditions with the increase of pre-bend value of the blade-tip,the ultimate loads of the blade root and the dynamic deformations of the blade section near the blade-tip increased significantly.By through the frequency-domain analysis of the pre-bend 5 m blade,resonance occurs near the first natural frequency in edgewise and torsional deflection,which means that the oversize amount of the pre-bend value in blade-tip will cause instability problems.