Theoretical aerodynamic methods for VAWT analysis

The peculiarities of vertical-axis wind turbines (VAWTs), such as simple blade building and the absence of an orientation system, are studied. A comparison is made of three theoretical methods quantified by means of an overall parameter as the average coefficient of power. The importance of advanced-flow analysis media, such as vortex models or finite-difference models, is shown in their ability to capture flow details, as illustrated by some examples. Such an accurate knowledge of wind evolution near the rotor is necessary to project high-efficiency turbines and to design their structural elements