大型风力机周围流场及气动特性仿真分析

Simulation Analysis of Flow Field and Aerodynamic Characteristics of Large Wind Turbine

风力机上的气动载荷与风力机周围流场有关,气动载荷和弹性力等交变载荷引起柔性风轮、塔架等部件振动变形,风力机部件振动变形影响风机周围流场,对风力机测风技术提出更高要求,而高分辨率风速测量对风力发电机组的控制和载荷计算具有重要意义。采用基于滑移网格的计算流体动力学仿真(CFD)和基于动网格的流固耦合仿真(FSI)研究大型风力机,探究风力机周围流场演化和柔性叶片变形特性,可以降低现场试验和风洞试验成本,为风速预测模型提供验证数据。结果表明,CFD和FSI仿真模拟风力机的来流效应和尾流效应和理论值接近,FSI仿真可模拟风力机风轮最大应力和最大应变的幅度和位置。

The aerodynamic load on the wind turbine is related to the flow field around the wind turbine.The alternating loads such as aerodynamic load and elastic force of the wind turbine cause the vibration deformation of flexible wind wheel,tower and other components.The vibration deformation of wind turbine components affects the flow field around the wind turbine,which puts forward higher requirements for wind measurement technology of wind turbine,and high-resolution wind speed prediction is of great significance to the control and load calculation of wind turbine.In this paper,Computational Fluid Dynamics simulation(CFD)based on sliding mesh and Fluid Structure Interaction simulation(FSI)based on dynamic mesh are used to study large-scale wind turbine,and explore the relationship between the deformation behavior of flexible blades and the evolution of flow field,which can reduce the cost of field test and wind tunnel test and provide verification data for wind speed prediction model.The simulation results show that the inflow effect and wake effect of wind turbine simulated by CFD and FSI are close to the theoretical value.FSI simulation can simulate the amplitude and position of the maximum stress and maximum strain of the wind turbine.