带偏航角串列式两风机复杂尾流场数值模拟

在多风机风电场中,通过主动调节上游风机的偏航角度,抑制上游风机尾流对下游风机的影响,减少风力机机组之间的尾流相互干扰,以达到提高整个风电场效率的目的。采用基于开源平台Open FOAM自主开发的FOWT-UALM-SJTU求解器中风电场求解模块ALMWindFarmFoam,将致动线模型与CFD方法相结合,利用大涡模拟(LES)计算研究当上游风机处于不同偏航角度时,两风机之间的复杂尾流干扰效应。对比分析偏航角度改变时,上下游风机气动功率的输出特性,尾流速度变化以及风机的尾涡结构。数值模拟结果表明:在上下游风机沿流向方向距离保持不变的情况下,随着上游风机偏航角度的变化,上下游风机的尾流干扰现象以及下游风机的入流条件会发生明显改变,并会对下游风机的气动功率输出以及两风机风电场的整体流场产生显著影响。

Numerical study of wake interaction between two wind turbines operating in different yaw angles

In wind farms, the downstream wind turbines are distributed by the upstream wake, and the wake interaction among wind turbines has a great influence on the performance of the wind turbines. To reduce this effect, a control strategy based on the yaw angle can be a method for actively controlling the direction of the wake, and thereby improving the power output of whole wind farm. In this paper, large eddy simulations combined with the actuator line model are conducted in the in-house CFD code FOWT-UALM-SJTU Solver based on open source CFD platform OpenFOAM to simulate the wind farm which contains two tandem wind turbines when the upstream wind turbine is operated in different yaw conditions. According to the analysis of power outputs, wake characteristics, and vortex structures, when the upstream wind turbine is operating in the different yaw conditions, the behavior of the wake and the inlet condition of the downstream wind turbine will be affected to a great extent. And the yawed wake will also have a significant influence on the aerodynamic power output of the downstream wind turbine and the whole flow field around the wind farm.