双叶片半转叶轮水轮机水动力性能实验研究

Experimental investigation of Hydrodynamic Performance of Tidal Turbine with Double-blade and Half-rotating Impeller

双叶片半转叶轮水轮机是一种升阻复合新型垂直轴水轮机,水动力性能优劣直接影响着其工程应用价值。本文首先介绍了双叶片半转叶轮水轮机工作原理,分析了主要性能参数与实验参数的关系;在水轮机样机制造和水下实验平台设计的基础上,开展了水轮机低速启动性能测试、不同流速下获能效率测试以及获能效率稳定性测试等水下实验项目,并将水下实验与数值模拟进行结果对比分析。实验结果表明:双叶片半转叶轮水轮机在低流速(0.5 m/s)下依然保持良好的启动特性,来流速度对水轮机获能效率影响较小,最佳负载下水轮机平均获能效率可达46%,明显高于传统垂直轴水轮机获能效率;提高能量输出稳定性是该水轮机设计研究下一步需要努力的方向。

Double-blade half-rotating impeller tidal turbine(DHITT) is a new kind of lift-drag composite vertical tidal turbine. Hydrodynamic performance had a direct impact on its engineering application for DHITT. The working principle of DHITT was firstly introduced, and the relationship between the main performance parameters and the experimental parameters of DHITT was analyzed. Based on DHITT prototype and experiment platform, the underwater experiment schemes, including low income flow velocity start-up performance test, coefficient of energy extraction test and coefficient of energy extraction stability test at different income flow velocity had been carried out, and the relationship between the simulation results and the experimental was contrastively analyzed. The experimental results showed that DHITT maintained a good start-up characteristic at low income flow velocity(0.5 m/s), and the income flow velocity had slight influence on the coefficient of energy extraction of DHITT. The average coefficient of energy extraction of DHITT under optimal load can be nearly 46%, which was significantly higher than that of those traditional vertical turbines. The next research direction of DHITT is to improve the stability of the energy output.