Design, Analysis and Fabrication of Leading Edge Tubercles (let) on Vertical Axis Wind Turbine Blade

Abstract

The project analyzes the effect of Leading Edge Tubercle (LET) on a vertical-axis wind turbine. The Leading Edge Tubercles tend to decrease the wake region in a stream- lined body, resulting in reduced drag and avoid stall at higher angles of attack. First, NACA 0018 profile is selected. CFD analysis is done on simple NACA 0018 without tubercles on its leading edges. The results are validated. Then, Tubercles are made on the blade and CFD analysis is done. The results show a significant increase in lift to drag ratio of turbine blade with tubercles. To further increase the lift and reduce the drag cambered airfoil is used. For this purpose, unsymmetric airfoil DU06W200 is selected and its CFD analysis shows improved Lift and Drag coefficients compared to NACA0018. Then, in order to enhance the performance, different parameters of tubercles like wavelength, amplitude, angle of attack, altering span wise length of tubercles portions on the blade and camber of the airfoil are changed to study their effect on performance. The results suggest that LET enhances turbine performance by reducing vortex generation, wake region and increasing lift to drag ratio.

Key points: Leading edge tubercles (LET), CFD, lift-drag ratio, NACA 0018, DU06W200, Vertical Axis Wind Turbine.