Effect of Impulse Turbine Geometry on the Performance of a Dual-Turbine System for Wave Energy Conversion

Wells turbine, widely used to harness the wave energy, has high efficiency at a low flow rate. However, it has severe stall problem. In order to alleviate this problem, a dual-turbine system of Wells turbine with a booster impulse turbine was proposed. In the present study, the effect of impulse turbine geometries on the performance of combined turbine system was investigated by CFD analysis. As a result, the boosting effect of impulse turbine depends on the pressure differences that caused by the setting angles at a high flow rate. Moreover, the decrease of flow rate with the setting angle has a significant influence on the efficiency.