垂直轴风力机动态流场及其气动性能分析

摘要

Aerodynamic performance analysis is very important during vertical axis wind turbine(VAWT)design and experiments.The analysis of dynamic flow field is also important to test the performance of one VAWT.A two-dimensional interaction model is constructed to simulate the NACA0012 symmetric airfoil.By using k-ω SST turbulence model and sliding meshes,the distribution of fluid field around Darrieus straight-blades VAWT during runtime is obtained with the CFD software.By analyzing the velocity and vorticity of the airfoil at different azimuth,it is found that the flow separation generates at the azimuth of 105°,which leads to stall.Due to the influence of the wake at the up wind on the airfoil flow field at the down wind,the flow separation is not observed.%垂直轴风力机气动性能研究是风力机设计、实验的重要部分，对其运动状态下的流场进行分析是观测垂直轴风力机性能重要环节。基于 NACA0012对称翼型，建立二维几何模型并进行模拟计算。采用 k－ω SST 湍流模型及滑移网格技术，通过 CFD 软件数值计算得到达里厄型直叶片垂直轴风力机运行时周边流场分布情况。通过比较不同方位角下流场涡量以及升、阻力系数得出：在方位角为105°附近时，翼型下表面产生流动分离，并导致失速；下风区翼型运行的流场由于受到上风区尾流的影响，翼型周围没有产生明显的流动分离。