CFD Based Analysis and Parametric Study of a Novel Wind Turbine Design: the Dual Vertical Axis Wind Turbine
Small Vertical Axis Wind Turbines (VAWTs) are good candidates to extract energy from wind in urban areas because they are easy to install, service and do not generate much noise; however, the aerodynamic efficiency of small turbines is low. Here in a new turbine, with high aerodynamic efficiency, is proposed. The novel design is based on the classical H Darrieus VAWT. VAWTs produce the highest power when the blade chord is perpendicular to the incoming wind direction. The basic idea behind the proposed turbine is to extend that said region of maximum power by having the blades continue straight instead of following a circular path. This motion can be performed if the blades turn along two axes; hence it was named Dual Vertical Axis Wind Turbine (D VAWT) The analysis of this new turbine is done through the use of Computational Fluid Dynamics (CFD) with 2D and 3D simulations. While 2D is used to validate the methodology, 3D is used to get an accurate estimate of the turbine performance. The analysis of a single blade is performed and the turbine shows that a power coefficient of 0.4 can be achieved. So far, reaching performance levels high enough to compete with the most efficient VAWTs. The D VAWT is still far from full optimization, but the analysis presented here shows the hidden potential and serves as proof of concept. The study of the D VAWT is concluded with a preliminary parametric study of the turbine sensitivity to different incoming wind angles, turbine axes spacing, number of blades, airfoil profile and blade mounting point.