内含实体对H型垂直轴风力机气动性能的影响

以H型垂直轴风力机及其内含圆柱形实体为研究对象,对NACA0018翼型的五叶片H型垂直轴风力机的气动性能进行数值模拟和实验验证。分析8种不同直径的内含圆柱体,在内含实体截面积占风轮迎风面积之比分别为21.2%、50.0%和76.9%时,风力机风能利用率的峰值分别下降8.04%、20.7%及74.3%。结果表明：随着内含实体直径的增大,风能利用率的峰值逐渐减小,开始较为缓慢,达到一定值时快速下降。小直径内含实体主要影响叶片在下风区的转矩,对风能利用率的影响较小,而大直径内含实体还会影响叶片在上风区的转矩,其风能利用率迅速减小。对于内含固定直径的实体,比如在现有建筑物外侧安装风力机时,其风轮半径的选择需综合考虑风能利用率和风力机的建造成本两方面的因素。研究结果可为建筑物与垂直轴风力机进行有效结合以提高风能的利用提供参考。

INFLUENCE OF INTERNAL ENTITY ON AERODYNAMIC PERFORMANCE OF H-TYPE VERTICAL AXIS WIND TURBINE

Taking H-type Vertical Axis Wind Turbine (VAWT) and its internal cylindrical entity as the research object, the aerodynamic performance of five blade H-type VAWT with NACA 0018 airfoil is studied by numerical simulation and experiment. Eight different diameters of internal cylindrical entity are investigated. It is shown that the peak power coefficient of VAWT decreases by 8.04%, 20.7% and 74.3% when the ratio of the internal cylindrical entity cross-sectional area to the sweep area of the VAWT is 21.2%, 50.0% and 76.9% respectively. The peak value of power coefficient of wind turbine gradually decreases with the increase of the internal entity diameter. It starts slowly, but drops rapidly when the diameter reaches a certain value. It is found that the internal entity with small diameter mainly affects the torque of the blade in the downwind area, and it has little impact on the total power coefficient, while the internal entity with large diameter will also affects the torque of the blade in the upwind area, and the total power coefficient decreases rapidly. For the internal entity with fixed diameter, such as the wind turbine installed outside the existing buildings, the selection of the wind turbine radius should take into account both the factors of power coefficient and construction cost. The research results can provide reference for the effective combination of buildings and VAWT to improve the utilization of wind energy.