Numerical computation on self-starting position of a three-blade vertical axis hydro-turbine

Abstract:

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.