Model test of multi-layer vertical axis tidal current turbine

Abstract

This study examines the efficiency of a vertical axis marine tidal current turbine according to various geometrical conditions of the turbine such as the number of blades and layers through numerical simulations and experiments. The vertical axis tidal current turbine of drag force type with arch-shaped blades is tested. From experiments in a circulating water channel and numerical simulations using a commercial computational fluid dynamics program, torque, angular velocity, power coefficient and tip speed ratio of the vertical axis tidal current turbine are obtained. The property changes for various conditions give the relationships between efficiency-related parameters. The maximum power coefficients of both simulations and experiments occur at the tip speed ratio of approximately 0.4∼0.5. From the experiments, the doubled layer turbine is found to give a 35% larger power coefficient than the single layer one.