水平轴潮汐透平场的数值研究

Numerical Investigation of Horizontal Axis Tidal Turbine Farm

为了研究水平轴潮汐透平的动力性能及透平周围流场的结构,在叶素理论(BE)、激盘模型和计算流体动力学(CFD)的基础上建立了一种可以计算潮汐透平动力性能和流场特征的BE+CFD方法,并在3种工况不同尖速比(TSR)下对透平的功率系数CP和轴向推力系数CT进行了计算,计算结果与实验结果吻合良好,表明所提方法是有效的.在此基础上,对单机透平周围流场进行了模拟,进而分析了透平下游流场的速度分布及透平阵列中横向距离对CP和CT的影响,结果显示:透平下游8倍直径中心处的流场速度值为入口速度时的86%;横向距离对CT影响较小;横向距离减小时CP呈增加趋势.该结果可为水平轴潮汐透平场设计提供理论参考.

In order to study the dynamic performance of a horizontal axis tidal turbine and the structure of the flow field around it, a BEq-CFD method was developed on the basis of the blade element theory, the actuator disc model and CFD techniques. The power coefficient Cp and the axial thrust coefficient CT for the turbine were computed at three tip speed ratios （TSR）. The predicted results agree well with the experimental data. Then, the simulation on the flow field around the turbine was performed, and the downstream velocity distribution of the turbine and the influence of lateral distance on Cp and CT were analyzed. The results show that the center flow velocity located at the place with a distance of eight times the rotor diameter behind the tur- bine downstream is about 860//oo of the inlet velocity. The discussion on the relationship between the lateral distance and CT, Cp shows that the lateral distance has slight impact on CT, and Cp in- creases with the decrease in the lateral distance.