Vortex Field Visualization in the Near Blade Region of a Vertical-Axis Marine Hydrokinetic Turbine

Abstract Vertical-axis hydrokinetic turbines offer a high-power-density solution for marine energy, yet their performance is constrained by complex wake interactions. This study utilizes time-resolved particle image velocimetry (PIV) to investigate the near-blade vortical fields of a tandem turbine system. By capturing the impingement of upstream trailing-edge vortices on downstream blades, we elucidate how dynamic stall and the subsequent shedding of the leading-edge vortex (LEV) modulate lift and torque in highsolidity rotors.