潮流发电帆翼式柔性叶片水轮机实验研究

Experimental investigation on sail-winged flexible blade turbine

潮流发电水轮机是海洋潮流能发电系统的核心组成部分。帆翼式柔性叶片水轮机是一种全新水流发电装置,叶片由柔性材料制成,在流体力作用下自动调节攻角,能充分利用流体的升力和阻力效应做功。以帆翼式柔性叶片水轮机获能系数为研究目标,采用因次分析法初步分析可能影响获能系数的因素,通过模型实验对叶片弧弦比、叶片边弦比、叶片密度与获能系数的关系进行研究。不同结构形式转子存在不同叶片弧弦比最佳值,叶片边弦比愈大,获能能力愈强;在一定范围内,叶片密度较小时,获能与起转能力强,转速波动性较大,适用于低流速工况;反之获能与起转能力弱,稳定性较好,电能质量较高,适用于高流速工况。最后提出优化方案,实验证实优化后水轮机在获能能力和发电能力上均有所提高。

Turbine is the core component of power generation system extracting energy from tidal current. Sail-winged flexible blade turbine is a newly developed device generating power from water. Its blades are made of soft materials, which keep transforming continuously to adapt to the flowing liquid. In this way, the flexible blades can adjust attack angle automatically and make full use of lift and drag to extract energy. Focusing on the power efficiency coefllcient （ Cp ） of the sail-winged flexible blade turbine, the factors that may affect Cp were analyzed with dimensional analysis method. Then the relationship between Cp and arc chord ratio （ACR）, side chord ratio （SCR）, and blade density （λ） was studied via model tests. The results show thai the rotor possesses different optimal values of ACR depending on structures. Cp increases with the increase of SCR. In certain ranges, the slarting ability, Cp and the fluctuating of rotor speed become higher with the decrease of λ. So the rotor with lower 2 is applicable to low-flow conditions. Otherwise, the rotor with higher ）, has lower starting ability, Cp and fluctuating of rotor speed, which is applicable to high-flow conditions to generate higher quality power. Finally, the optimum schemes are proposed, and the optimized turbine is proved to have higher Cp anti power generation capacity through model tests.