Large-eddy simulation of helical- and straight-bladed vertical-axis wind turbines in boundary layer turbulence

Turbulent wake flows behind helical- and straight-bladed vertical axis wind turbines (VAWTs) in boundary layer turbulence are numerically studied using the large-eddy simulation (LES) method combined with actuator line model. Based on LES data, systematic statistical analyses performed to explore effects of blade geometry characteristics turbine wake. The time-averaged velocity fields show that helical-bladed VAWT generates a mean along center wake, which causes inclination alters gradient streamwise velocity. Consequently, intensities turbulent fluctuations Reynolds shear stresses also affected by helical-shaped blades when compared those case. results reversing twist direction spatial patterns flow statistics be reversed direction. Moreover, mass kinetic energy transports wakes directly visualized transport tube method, comparison between cases significant differences downstream evolution tubes.