三叶片垂直轴水轮机自启动性能数值计算

摘要

为寻求固定偏角垂直轴水轮机的启动性能规律，应用CFX流体－刚体耦合运动求解方法实现了垂直轴潮流能水轮机自启动过程的瞬态数值模拟，结合静态启动力矩系数的计算结果，分析在不同初始方位角下水轮机的启动时间以及角速度的稳定情况。研究结果表明：对于三叶片固定偏角垂直轴水轮机而言，方位角在60°～130°范围内启动性能较好，但在90°位置静态力矩会出现突降，不利于自启动；方位角在140°～170°范围内启动性能较差，但系统阻尼为0时，在所有位置均能够实现自启动，且启动过程稳定后水轮机转速均达到飞逸转速。%For studying on start⁃up performance rules of fixed pitch tidal current turbine, the transient self⁃starting process of vertical axis hydro⁃turbine is numerical simulated by using CFX fluid⁃rigid body coupled motion calculating method. Combining static start⁃up torque coefficient results, the self⁃starting time and the angular speed stability of the turbine are analyzed in different initial azimuth angles. It is shown that, as for the three⁃blade fixed⁃pitch vertical axis hydro⁃turbine, the turbine has a better self⁃starting performance at azimuth angles of 60°~130°, but the angle of 90° is not a good choice because the static start⁃up torque will drop suddenly at this point. The turbine has a worse self⁃starting performance at azimuth angles of 140°~170°. However, the three⁃blade vertical axis hydro⁃turbine has self⁃starting performance at any initial position when the system damping is zero and the angular speed of the main shaft can arrive at runaway speed finally.