Inverse Design of Blade Shapes for Vertical Axis Wind Turbines

An inverse design process is applied to determine blade shapes used in vertical axis wind turbines (VAWTs). The method is based on the modified Garabedian-McFadden technique that uses the deviation of the pressure distribution or the velocity distribution on the surface from a target pressure or velocity distribution, and modifies the blade surface in order to reduce this deviation. The method was originally developed for wing design and applied for such aerofoil shapes as those of horizontal axis wind turbine blades. The procedure is employed here successfully to find a target shape that is used in a VAWT operating with blades of constant thickness rather than of aerofoil shape. The method is presently applicable to determine blade shapes in a two dimensional section, and considers some performance criteria of VAWTs; thus, it contributes to finding blade shapes that most closely corresponds to the efficient operation of such turbines.