大气边界湍流场对风力机尾流特性影响的试验研究

In modern wind farm, wind turbines are arrayed in matrix. The effects of wake interact resulting in reduced power generation and increased fatigue loads of downstream wind turbine. In order to reduce power loss and improve blade rotor life, it is important to understand turbulent characteristics in the wakes, especially the influence of wake interaction on blade loads and aero-elastic response .Although, many experimental studies have been conducted on wake , It should be noted that most of them were conducted with the wind turbine models installed in air flow with homogenous, uniform incoming flow velocity and relatively low turbulence intensity. However, in reality, most of the wind turbine operate in atmospheric boundary layer winds with significant variations in both incoming wind speed and turbulence intensity. However, in reality, most of the wind turbine operate in atmospheric boundary layer winds with significant variations in both incoming wind speed and turbulence intensity. The effects of the significant variation in mean and turbulence characteristics of the atmospheric boundary layer winds on the power productivity ,dynamics wind loads and evolution of the unsteady tip vortices in wake of wind turbine have not been fully exploered.Especially,the effects of the Wake interaction on the power productivity, dynamics wind loads of downstream wind turbine at atmospheric boundary layer have not been fully exploered. Based on the technique that using spires and roughness elements to simulate the atmospheric boundary layer in large-scale wind tunnel, this proposal is going to study the effects of the significant variation in mean and turbulence characteristics of the atmospheric boundary layer winds on the power productivity, dynamics wind loads and evolution of the unsteady tip vortices in wake of single modeled wind turbine, and the effects of wake interactions on the power productivity, dynamic loads and aero-elastic response of two tandem modeled wind turbines in atmospheric boundary layer. The experimental data are valuable for the development of wake model and wind farm layout.

风场中风力机集中布置，下游风力机的出力和安全受上游风力机尾流的影响。为了减少功率损失，改善叶片寿命，务必对风力机尾迹进行深入了解。虽然人们已经进行了大量的研究探索，但是大部分研究来流条件为均匀来流且湍流度较低，而实际风力机运行在大气边界层内，大气边界层是复杂的低速剪切湍流层。大气边界层中平均风速和湍流度的显著变化对风力机出力、动态载荷及尾流场特性及叶尖涡发展的影响研究还比较缺乏，尤其是大气边界层湍流场及风力机尾流干扰叠加作用下，下游风力机功率损失和叶片动态载荷之间的影响规律等方面需要进一步的研究。本项目通过在风洞中合理布设尖劈和粗糙元等边界层发生装置模拟大气边界层流动特性，并以单台和两台模型风力机为研究对象，研究大气边界层湍流场对风力机尾流的流场特性和湍流结构的影响及对风力机尾流干扰的影响规律，揭示大气湍流及尾流叠加作用下风力机出力及动态载荷变化的科学规律，对于风场的排布优化有着重要意义。

风电场中风力机集中布置，下游风力机的出力受上游风力机尾流的影响。为了减少功率损失，改善叶片寿命，需要对风力机尾迹进行研究。此外，风力机叶片运行过程中在叶展易发生流动分离，降低叶片捕获风能的效率，通常在叶片上添加增升减阻装置进行流动控制以减小或延缓流动分离，达到提高叶片气动性能的目的。增升减阻装置对风力机专用翼型气动特性影响的实验研究相对比较缺乏，需要对其流动控制机理及设计参数对流动控制效果的影响进行深入的实验研究。. 本项目采用风洞实验的方法，首先针对风力机专用翼型DU93-W-210加装涡流发生器、格尼襟翼、锯齿尾缘进行了详细的实验研究，揭示了涡流发生器、格尼襟翼等增升减阻装置对风力机翼型流动控制的机理；给出了涡流发生器、格尼襟翼的几何尺寸、安装位置、排列方式等因素对流动控制效果影响的规律。研究结果对于增升减阻附件在提高风力机叶片气动性能的设计、使用提供了参考依据，具有一定的应用价值。 其次，针对风力机尾流特性的研究，本项目以单台模型风力机为研究对象，进行风洞实验。研究了不同工况下风力机的出力特性以及尾流的流场特性。研究结果对于风电场的排布优化有着一定的参考意义。