Experimental Study of Regenerative Wind Farms Featuring Enhanced Vertical Energy Entrainment

Abstract. This study presents the experimental validation of regenerative wind farms (RGWFs), a novel wind farm concept designed to enhance overall wind farm performance. RGWFs employ Multi-Rotor Systems with Lifting devices (MRSLs), an innovative wind energy harvesters engineered to promote strong vertical energy entrainment, thereby accelerating wake recovery. In the experiments, MRSLs are scaled for wind tunnel testing, with their rotors modeled using porous disks and their lifting devices represented by airfoils. The tested RGWFs comprise up to three by three MRSLs. Flow quantities within RGWFs and aerodynamic loads on MRSLs are measured using volumetric particle tracking velocimetry and strain gauges, respectively. Compared to conventional wind farms, flow analysis indicates that RGWFs significantly enhance vertical energy entrainment, as evidenced by a more than 200 % increase in thrust on second-row-MRSLs. These experimental results, consistent with previous numerical predictions, highlight the promising potential of RGWFs.