山体地形中粗糙度对风速的影响研究

STUDY ON INFLUENCE OF ROUGHNESS ON WIND SPEED IN MOUNTAIN TERRAIN

采用CFD方法对影响情况进行研究,首先利用三维软件生成某实际案例复杂地形的模型,进行不同湍流模型在西南风下各测点位置模拟速度与实际风速的比较,表明Realizable κ-ε模型误差较小;再模拟不同粗糙度、坡度及地貌类型对简单二维、三维地形、实际案例复杂地形的风速影响。结果表明:在简单二维和三维中,在相同坡度下,A、B类地貌中迎风面和背风面上的风速随粗糙度的增大而变小;而在C、D类地貌却变大;顶点在4类地貌中的风速随粗糙度的增大而变小。复杂地形在B类地貌中的风速随粗糙度的增大而变小,但变化幅度不是很大。

The CFD method is used to study the influence on wind speed.At first,three-dimensional software is used to generate the model of a complex terrain of a real case,the comparison of simulation wind speed and actual wind speed is carried out at different measuring points of different turbulence models under southwest wind,and showing the error of Realizable κ-ε model is smaller.Then the effect of different roughness,slope and landform types on the wind speeds of simple two-dimensional,three-dimensional landforms and complex landform of actual case is simulated.The results show that in simple two-dimensional and three-dimensional landforms,the wind speeds on the windward and leeward faces in the A and B landforms becomes smaller as the roughness increases under the same slope,and the wind speeds for C and D landforms become larger;The wind speeds in the vertices of the four types of landforms become smaller as the roughness increases.In the complex landform,the wind speed decreases with the increase of roughness in the B landform,but the variation is not very large.