Two-dimensional model of wind flow on buildings to optimize the implementation of mini wind turbines in urban spaces

Abstract

The roofs of the buildings present a very valuable source of renewable energy: wind. Similar to the study of the perfect location for wind generators in the natural environment, we need to have models for characterization of wind in the urban space to optimise the locations of the mini wind turbines in that space as well as the chose of the most appropriate type. The scientific study of the implementation and optimisation are the basis for a line of research developed by our group in recent years. Its most important results and main conclusions are presented in this paper. The separation angle is greater near the edge of the roof of the building and varies with wind speed. The higher the building, the greater the separation angle reached, reaching even 90°. For low buildings that angle will be imperceptible. The more rugged is the area near the building the lower the angle of separation. The wind turbines have to be placed always at a height above the separation bubble, in order to avoid the slow speeds as well as significant turbulences. Furthermore it is noteworthy that the wind turbines will benefit from an increase of 20% of air velocity compared with the wind at the same location if there was no effect of the building. That is, the urban space provides an extra increase of wind power, provided that the location of wind turbines is optimised.