双向直驱式潮流能发电轮机性能实验研究

Experimental study on the performances of bidirectional direct-drive power turbine

针对潮流能双向来流的特点及当前潮流能发电轮机的研究现状和存在的问题,提出了一种新型的双向直驱式发电轮机。叶片基本翼型为S型,并对其进行受力分析,得到相应的计算公式,结合叶片翼型厚度和形状约束,求解出各个截面的形状,并三维建模形成一种新型"S"翼型轮机。轮机两端安装具有防水性能的永磁发电机,外侧增设双向导流罩,构成双向直驱式发电轮机装置模型。在水槽实验中,首先找出不同的模拟流速下获取功率的最佳负载阻值,在此基础上收集了转速及功率数据,绘制尖速比-获能系数关系曲线图和流速—获能系数关系曲线图,可以论证尖速比的取值对获取最佳功率的重要性,同时该翼型轮机具有良好的空载启动性能及双向吸收来流的能力,2 m/s流速下获能效率最大值接近40%。

Aiming at the characteristics of two-way flow of tidal current, the research status and the existing problems of current tidal turbine, a new bidirectional direct-drive power turbine is proposed. The basic airfoil of the blade is S-shaped. By analyzing its force, the corresponding formula is obtained, and based on the thickness and shape constraint of the blade airfoil, the shape of each section is calculated, then a new ＇ S＇ airfoil turbine is formed by 3D modeling. A permanent magnet generator with waterproof performance is installed at the two sides of the turbine, and a bidirectional shroud is added to the outside of the turbine to form a bidirectional direct-drive power turbine model. In the flume experiment, the optimal load resistance of the power is obtained under different simulated flow velocities. On this basis, the rotational speed and power data are collected, thus drawing the curves of tip speed ratio - power coefficient and flow velocity - power coefficient. The figure shows the importance of the numerical value of the tip speed ratio to get the best power, and the airfoil has good ability of no-load start-up and bidirectional absorption flow. The maximum efficiency of the power turbine is close to 40% at 2 m/s.