Computational fluid dynamics analysis of the vertical axis wind turbine blade with tubercle leading edge

The performance of a vertical axis wind turbine (VAWT) blade with NACA0015 airfoil section has been investigated using the commercial computational fluid dynamics software ANSYS FluentTM. The Semi Implicit Method for Pressure Linked Equations algorithm is chosen to solve the incompressible Navier-Stokes equations. The k-ω shear stress transport turbulence model was selected for the turbulence flow simulations. The simulation results of lift and drag coefficients between angles of attack of 0° and 40° were first validated with the experimental data in order to confirm the boundary layer distributions. The grid numbers and time step sizes were then examined to confirm the simulation accuracy. To exam the 3D effect, a 2.5D model was additionally developed and compared with 2D model. Finally, the predictions of thrust obtained from the blade with tubercle leading edge were compared with the ones from the straight blade. Overall, the thrusts of VAWT with modified turbine blades were lower than the ones with straight blade. The values of the thrust decreased with increasing amplitudes and decreasing wavelengths, mainly due to the structure of the vortices generated at the leading edge of the turbine blade.