基于LBM-LES方法的典型复杂地形作用下风力机尾流数值模拟

Numerical Simulation of Wind Turbine Wakes in Typical Complex Terrains Based on LBM-LES Method

为研究典型复杂地形作用下风力机尾流结构特性,采用了基于格子玻尔兹曼方法和大涡模拟方法的数值模拟方法。为验证计算模型的可靠性,选用3种亚格子湍流模型对MEXICO风力机进行数值计算,发现WALE模型的计算结果更为准确。然后采用WALE模型计算分析了不同坡度典型山丘地形作用下2 MW风力机流场结构,同时与平坦地形中的尾流结构对比发现:位于山丘顶部的风力机尾流与山丘背风面的回流区相互作用,尾流旋涡和背风面脱落涡相互掺杂,尾流会在高度方向上沿坡面下移,坡度越小时,尾流的下移与贴面效应越明显。

In order to study the characteristics of wind turbine wake in typical complex terrains,a numerical model based on lattice Boltzmann method(LBM)and large eddy simulation(LES)was adopted.To verify the reliability of the calculation model,three sub-grid scale turbulence models were selected to simulate the flow field induced by the MEXICO wind turbine.It is found that the wall adaptive local eddy(WALE)model performs better than the others investigated.Then,the flow field of a 2 MW wind turbine on typical hills with different slopes was calculated and analyzed by using the WALE model.The results were compared with that in the flat terrain.It is found that the wind turbine wake at the top of the hill interacts with the backflow on the leeward side of the hill.The wakes of both wind turbine and hill on the leeward side are mixed with each other,and the wake of wind turbine will move downward along the slope of the hill when the slope is small.