中文摘要：

垂直轴潮流能水轮机具有结构简单、适应任意流向等优点,但其能量转换效率低于水平轴水轮机,在运行时有较大的转矩脉动,不利于水轮机的平稳运行,易引起结构疲劳。本文针对垂直轴潮流能水轮机的运行特点,提出了一种导流涵道装置,利用数值模拟方法对比分析水轮机在有无导流涵道装置情况下的水动力性能。结果表明,导流涵道可以起到整流的作用,使流体在水轮机盘面内的流动更加平顺。另外,导流涵道装置不仅可以提高水轮机的能量利用率,还能有效改善作用在水轮机叶片上的水力驱动力矩脉动和转速脉动,改善了水轮机运行状态,提高了结构可靠性。

英文摘要：

Although vertical axis tidal turbine holds the advantages of simple structure and being able to work in any direction of flow, it has a lower power coefficient than horizontal axis tidal turbine. In addition, hydrodynamic torque on rotors also shows fluctuation in operation, which has negative effects on the smooth operation and structural safety of the turbine. Considering the drawbacks of vertical axis tidal turbine, this paper presents a feasible duct device, and compares and analyzes the hydrodynamic performances of non-ducted tidal turbine and ducted tidal turbine, respectively. The results show that the duct can smooth the flow in the whole circle of turbine. What is more, a ducted turbine can also capture more power from tides and reduce the fluctuation of hydrodynamic torque on rotors and rotational speed of the turbine, which will benefit the structural safety.