潮流能水平轴水轮机叶片扭角与弦长分布研究

Study on Twist Angle and Chord Length Distribution of Horizontal Axis Tidal Current Turbine

叶片是潮流能水轮机的关键部件,为获取综合性能良好的潮流能水平轴水轮机,采用解析计算与CFD仿真结合的方法研究叶片扭角与弦长分布。以叶素效率最大原则,推导叶片扭角与弦长的理想分布计算模型,并研究尖速比对叶片扭角与弦长分布的影响;综合考虑水轮机获能效率、可靠性、安全性及叶片加工制造等因素,提出对叶片扭角与弦长修正分布模型;运用Fluent软件对20kW水轮机设计实例性能分析,结果显示修正模型水轮机转矩满足获能要求,轴向力明显减小,有利于工程应用中水轮机的稳定运行。

General performance of the blades is important to horizontal axis tidal turbine(HAT).The twist angle and chord length distribution of turbine blade were studied by using analytical methods combined with CFD simulation in this paper.The ideal distribution model of twist angle and chord length was derived,according to the principle of the blade-element maximum efficiency.The influence of tip-speed radio on twist angle and chord length distribution was investigated.Then a revised distribution model of twist angle and chord length was proposed,considering the energy capture efficiency,reliability,security of turbine and the processing and manufacturing of blade.By using software FLUENT,performance of a 20 kW revised model turbine was analyzed as an instance.The result shows that the turbine’s torque meets the requirements of power capturing and the turbine’s axial force is reduced significantly which are beneficial to stable operation of the turbine.