Wake interactions behind individual-tower multi-rotor wind turbine configurations

Abstract Multiple rotors on single structures have long been proposed to increase wind turbine energy capture with no in rotor size, but at the cost of additional mechanical complexity yaw and tower designs. Standard turbines their own very-closely-spaced towers avoid these disadvantages create a significant disadvantage; for some directions wake turbulence enters swept area very close downwind causing low output, fatigue stress, changes recovery. Knowing how performance pairs closely spaced varies direction is essential design layout that maximizes useful minimizes losses stress other directions. In current work, high-fidelity large-eddy simulation (LES) code Exa-Wind/Nalu-Wind used simulate interactions from paired-rotor configurations neutrally stratified atmospheric boundary layer investigate feasibility. Each pair consists two Vestas V27 hub-to-hub separation distances 1.5 diameters. The on-design results are consistent previous literature. For an off-design 26.6°, indicate little change power far-wake recovery relative case. At 45.0°, rotor-wake produce also velocity deficit intensity. A severely case considered.