不同强度湍流风对风力机气动载荷的影响

Influence of Turbulent Wind of Different Intensity on Aerodynamic Load of Wind Turbine

湍流强度是影响风力机载荷的重要因素之一。基于OpenFAST软件对NREL-5MW风力机进行了不同强度湍流风为入流条件下的数值计算,利用Turbsim软件生成的5%、10%、15%和20%这4种湍流强度的湍流风作为入流条件,探究了不同湍流强度对风力机叶根处的剪切力和弯矩的影响,并分析了不同湍流强度下风力机叶片整体的载荷分布情况。结果表明:随着湍流强度的增加,风力机的气动载荷和气动功率波动幅值相应出现规律性的增加,但大体变化趋势不变。10%、15%和20%湍流强度下的气动功率标准差比5%湍流强度下的分别高出87%、163%和243%,摆振弯矩标准差比5%湍流强度下的分别高出30%、64%和95%;叶片上的弯矩载荷从叶根向叶尖方向逐渐减小,且随着湍流强度的增加,叶片上的弯矩标准差值也随之增加,在叶根处差别最大,从叶根向叶尖方向逐渐减小,到叶尖处完全重合。且10%、15%和20%湍流强度下的叶根处第一个节点位置的挥舞弯矩比5%湍流强度下的摆振弯矩分别高出44.94%、93.1%和137%。湍流强度的增加对叶片的摆振弯矩影响最大。

Turbulence intensity is one of the important factors affecting the load of wind turbine.The numerical calculation of NREL-5MW wind turbine with different turbulence intensity turbulent wind as the inlet condition is carried out based on the OpenFAST software,and the turbulent wind with four turbulence intensities of 5%,10%,15%and 20%generated by the Turbsim software is utilized as the inlet condition to investigate the effect of different turbulence intensities on shear force and bending moment at the root of wind turbine blades,and analyze the overall load distribution of the wind turbine blades under different turbulence intensities.The overall load distribution of the wind turbine blade under different turbulence intensities is also analyzed.The results show that,with the increase of turbulence intensity,the aerodynamic load and aerodynamic power fluctuation amplitude of the wind turbine are increased regularly,but the general trend is the same.the standard deviation of the aerodynamic power at 10%,15%and 20%turbulence intensity is 87%,163%and 243%higher than that at 5%turbulence intensity,and the standard deviation of the oscillating bending moment at 10%,15%and 20%turbulence intensity is 30%,64%and 95%higher than that at 5%turbulence intensity,and the standard deviation of the bending moment on the blades is 30%,64%and 95%higher than that at 5%turbulence intensity;the bending moment load on the blade gradually decreases from the leaf root to the tip direction,and the standard deviation of the bending moment on the blade increases with the increase of the turbulence intensity,and the difference is the largest at the leaf root,which gradually decreases from the leaf root to the tip direction,and then completely overlaps at the tip.And the swing bending moment at the first node position at the blade root at 10%,15%and 20%turbulence intensity is 44.94%,93.1%and 137%higher than that at 5%turbulence intensity,respectively.The increase in turbulence intensity has the greatest effect on the swing bending moment of the blade.