An investigation into the possible effects of cavitation on a horizontal axis tidal turbine

This paper investigates the conditions under which cavitation may affect the operation of horizontal axis tidal turbines. The approach utilises computational fluid dynamics (CFD) to measure the individual and combined influence that operational parameters, including flow velocity, rotor angular velocity, and depth of submersion exert on the operation of a 3 bladed turbine. The approach is based upon the behaviour developed within a CFD model allowing the comparison of the minimum local pressure to fluid vapour pressures. It must be stated that the inception of cavitation may be a complex process. This approach thus assumes that when local fluid pressure drops below the vapour pressure cavitation will ensue. The result of this analysis suggests that, given specific conditions, it is highly likely that tidal turbines will be subject to the effects of cavitation.