Effect of Cavity Tip on the Performance of a Wells Turbine

A Wells turbine is used to harness power from the ocean waves. The turbine’s blade tip allows leakage, which reduces performance. This paper introduces a cavity on the tip to reduce the leakage and presents numerically simulated results. Reynolds-Averaged Navier–Stokes (RANS) equations were solved using a two-equation turbulence closure model in Ansys CFX. The cavity altered the leakage flow and affected the performance. The cavity increased pressure at the tip resulting in the early occurrence of the stall. Detailed performance and flow physics of both base and cavity tip blades are presented.