Numerical Study of a Vertical Axis Wind Turbine in Unsteady Inflow

This article investigates aerodynamic behavior of a straight three-bladed vertical axis wind turbine with NACA 0022 profile for the blades .Reynolds number in unsteady inflow study is about 8.5×105 .This type of turbine is inherently unsteady regarding to continuous changes of angle of attack, besides as in practice turbine interferes with unsteadiness due to wind gust , aerodynamic behavior and performance variations regarding to these effects is discussed by introducing sinusoidal fluctuating inflow. Turbulence is modeled by Transition K-ω equation which to be solved simultaneously with Unsteady Navier-Stokes equations. Performance at different tip speed ratios is calculated using computational fluid dynamics(CFD) and results are compared with experimental ones for validation purposes