Wake Dynamics and Synergistic Clustering Effects of Savonius Wind Turbines*

Vertical Axis Wind Turbines (VAWTs) have shown performance benefits when placed in clustered arrays for both full scale field tests and in Computational Fluid Dynamics simulations. However, less is known regarding the potential benefits of clustering on high-solidity designs such as the Savonius VAWT geometry. Ongoing work at Penn State uses Particle Image Velocimetry (PIV) to observe both transient and averaged flow fields behind turbine clusters in a water channel facility, and power production for each turbine in clusters of up to three are characterized in a wind tunnel. Power characterization shows negligible power losses as a result of clustering for any 2 turbine configuration, while some 3 turbine configurations showed significant performance increases. PIV data reveals several fluid behaviors unique to this Savonius geometry which may explain power performance behavior.