AERODYNAMIC DESIGN AND TESTING OF BLADE PROFILES FOR VERTICAL AXIS WIND TURBINES

摘要: The aerodynamic airfoil data, which is usually used for VAWT calculations, is defined (experimentally or numerically) for airfoils in steady uniform rectilinear translation. In the present work it is proposed to identify, from a theoretical numerical point of view, the aerodyna--mics of an airfoil in uniform rotation, so that a better estimation of the performance characteristics of the VAWT can be achieved. A coupled potential flow-boundary layer numerical method will be used. Airfoil data will be produced for a realistic range of values of the radius of rotation and for different Reynolds numbers. The equivalent calculations will be carried out also with an unsteady aerodynamic model which uses surface singularity distributions on the airfoil and its wake. For this model only the geometrical (and not the aerodynamic) characteristics of airfoils are needed, but the method is limited to non-viscous flow calculations. During the second phase the above procedures will be applied on one hand in order to evaluate the blade profiles which are usually used in VAWT applications, and on the other hand in order to determine those blade profiles which could produce optimised WT performance characteristics. The numerical modelisation of the second phase will determine certain airfoil forms which will be used during the third phase for the construction and testing of blades in a wind tunnel. The experimental part will include power efficiency, torque and velocity field measurements for each blade profile form.