复杂工况下的大型风力机气动弹性响应和尾迹数值分析研究

Numerical analysis for aero-elastic responses and wake of a large scale wind turbine under complicated conditions

在复杂工况下,大型风力机受到载荷更加严重,导致风力机气动和结构耦合响应问题更加明显。主要针对稳态偏航、动态偏航、风剪切和随机风速场等复杂工况,采用非定常自由涡尾迹方法计算尾迹形状和气动载荷,加入了复杂工况的模型,进行了动态失速模型和三维旋转效应模型修正。在考虑气动载荷、惯性载荷和重力载荷影响下,采用有限元法结合模态法建立起风力机解耦动力学方程,并且通过Newmark方法进行数值求解该方程。实现了复杂工况数值模拟计算,比较不同复杂工况的气动弹性响应结果。最后,得出大型风力机在复杂工况下的气动性能、载荷、动态响应和尾迹叶尖涡线特性,并计算出风力机在复杂工况下的迟滞时间。这为推进自由涡尾迹方法应用于大批工况载荷计算,以及提高大型风力机载荷计算精度和设计水平等具有重要意义。

Large scale wind turbines suffer serious unsteady loads under complicated conditions, it leads to their obvious aero-elastic coupled responses. For steady yaw, dynamic yaw, wind shear and stochastic wind field, the free vortex method was used to calculate their aerodynamic loads and wake shapes. The dynamic stall model and the three- dimension stall delay model were taken into account. At the same time, considering the aerodynamic load, inertial load and gravity load, the finite element method was combined with the modal method to build the deeoupled dynamic equations of a wind turbine, these equations were solved numerically with Newmark method. The aero-elastic dynamic responses under different complicated conditions were compared. Finally, the aerodynamic performance, load, dynamic responses and tip vortex line characteristics of wind turbines were deduced under complicated conditions. The results were significant for applying the free vortex method in load calculations of wind turbines, and improving the load calculations accuracy and design levels of large scale wind turbines.