CFD analysis of vertical axis wind turbine with modified blades for deployment in Ilorin, Kwara state, Nigeria

Abstract

Researchers and the energy industry are currently focusing their efforts on optimizing the effectiveness of vertical- axis wind turbines (VAWT) to cut down on the reliance on energy supply from fossil fuels which releases gases that are toxic to the environment. As such, several methods have been applied, including increasing the velocity and modification of both the trailing and leading edges of the aerofoil. In the present investigation, numerical studies of the flow on the wind turbine blades with a NACA0015 airfoil section equipped with and without tubercles on the trailing edge were conducted using ANSYS Fluent. A computational domain of 2000 mm by 35000 mm was employed with the K-W SST turbulence model. This two-dimensional computational fluid dynamics (CFD) analysis was performed with Ilorin, Kwara State, Nigeria wind data that was received from the Nigeria Meteorological Agency (NIMET). The modified blade with a wavelength of 90 mm and an amplitude of 4 mm is seen to have a better thrust than the unmodified blade. It produced a thrust of 118 N for a tip-speed ratio (TSR) of 4.0 compared to 109 N of the unmodified blade at the same TSR and that of the modified blade (1) which attains 107 N. Also, its coefficient of performance is 5% and 6% higher than that of the straight and modified blades (1) respectively, These results suggest that an increase in the tubercle’s wavelength and amplitude increased the maximum thrust.