Effect of Two-Dimensional Profile Optimization on Vertical Axis Wind Turbine Power Performance

In this study, performance of the blade profiles which was developed numerically and parametrically was examined experimentally for vertical axis wind turbine. In the parametric optimization study, angle of attack, mean (camber) line and thickness were taken as parameter, and the profile was optimized by using Ansys/Response Surface Optimization tool. After that, in the numerical optimization study, the lift and drag coefficients were taken as parameters and the profile was optimized and the blade profiles of NACA0012-alpha and NACA0012-beta, which would make the lift-to-drag ratio maximum, were obtained. The developed profiles were produced by 3D printer and the power data was measured experimentally for 3, 4 and 5 bladed turbines. The highest power was obtained in the 4-bladed turbine for all profiles. The power coefficient of 0.19 was obtained from a reference profile, while power coefficient of 0.24 was obtained from NACA0012-alpha profile and 0.30 from NACA0012-beta profile. The blade profile derived by numerical optimization reached 25% higher power coefficient than the blade profile derived by parametric optimization. It is found that lift coefficient on the power coefficient of the vertical axis wind turbine is more dominant than the drag coefficient.