Hydrodynamic Performance Assessment of Selected Hydrokinetic Turbine Blade Sections in River Oyun, North-Central Nigeria

Abstract

The hydrodynamic performance of lift-based hydrokinetic turbine rotors is typically dependent on the rotor blade sections, or the profile of the hydrofoil used. Different hydrofoil sections, with varying geometries, provide different efficiencies under diverse hydrodynamic conditions. Selecting the appropriate hydrofoil profile is crucial for achieving optimal hydrodynamic performance and helps in determining the ideal dimensions of a turbine. In this study, hydrodynamic performance tests were conducted on several pre-developed hydrofoils used in modeling hydrokinetic turbines, in River Oyun, Kwara State, North-Central Nigeria. Four hydrofoil profiles were selected, including the NACA 0021 fixed-pitch straight-bladed turbine rotor blade, NACA 16-021 fixed-pitch straight-bladed turbine rotor blade, NACA 4418 fixed-pitch cambered straight-bladed turbine rotor blade, and RISØ-A-12 fixed-pitch cambered straight-bladed turbine rotor blade. Their hydrofoil blade sections were modeled, and their performances were evaluated in a controlled riverine environment. The most suitable hydrofoil section was chosen based on rotor performance using the Cp-TSR ratio. Results show that the RISØ-A-12 and NACA 0021 blade sections achieved optimal performance, with Cp-TSR ratios of 0.486 and 0.481, respectively, presenting comparatively better performance.