Study on effect ofyawangle on hydrodynamics of tidal current turbine

When horizontal axis tidal current turbine works, yaw angle exists between water turbine axis and current flow direction. Analysis of experiment model was conducted, and comparison with experiment data verified the validity of this method. The angle between water turbine axis and current flow direction is yaw angle, which happens during turbine work. Based on three dimensional CFD numerical simulations, the effect of yaw angle on the hydrodynamics of turbine was studied, and the simulation results were compared with experiment results to verify the validity of simulation method. The influence of yaw angle on hydrodynamics of turbine was studied at in-flow and back-flow conditions, and numerical results showed that the average value of power efficiency and axial load decrease with increasing yaw flow. When yaw angle is 20°, power efficiency of inflow and back flow decrease 5% and 6%, respectively, while axial load decrease 5.5% and 7%, respectively, and higher yaw angle will cause the growth of instantaneous fluctuation value.