Influence of Lift to Drag Ratio on Optimal Aerodynamic Performance of Straight Blade Vertical Axis Wind Turbines

This paper defines an effective lift to drag for a vertical axis wind turbine design based on averaged torque per cycle. This metric is used to characterise the relationship between overall optimum aerodynamic performance and design parameters. A double multiple streamtube aerodynamic prediction model is employed to demonstrate the effect of lift to drag ratio on optimal power performance for the H-rotor and the V-rotor concept VAWT. A further study looks at the effect of coning angle for the V-rotor.