Numerical Investigation of Performance Improvement of A Wells Turbine Blade For Wave Energy Extraction.

Oscillating Water Column (OWC) is a wave energy converter that is considered one of the effective devices for generating power from the sea, and its importance has been of great attention over the last decade. The OWC has a bi-directional airflow, which moves the turbine connected to a generator to harness energy. A Wells Turbine stalls at higher angles of attack, and this reduces the performance of the turbine. To reduce this, we incorporated the use of strips on the suction side to investigate the turbines' performance. ANSYS™ CFX 2025 R1 was used to investigate the performance of the RANS model used in the setup for this simulation, coupled with the turbulence model k-ω SST. The non-dimensional parameters, such as the Torque Coefficient, Pressure Drop Coefficient, and Efficiency, were used to characterize the turbine’s performance. In total, four cases were simulated where strips were placed on the turbine blade, and the aim was to delay stalling on the blade and increase the operating range of the Wells Turbine. A detailed flow field visualization was completed to get an insight into the blade’s aerodynamic performance. However, the strips added huge vortices near the leading edge, which initiated the onset of stall on the blade and dropped the overall performance. The torque generated by the strips increased gradually to 60% of the chord length, producing the highest torque, and then decreased at 65%.