Investigation of kinetic energy recovery in the wake of a translating bluff body

A high-speed bluff body generates robust and coherent slipstream regions along its length, characterized by significant kinetic energy. Harnessing this available wind energy from the wake of a moving bluff body presents a novel approach for renewable energy recovery. The present study investigates the performance of a vertical-axis Savonius wind turbine positioned at varying proximities within the slipstream region using two-dimensional computational fluid dynamics (CFD) simulations. The flow field is modeled using Unsteady Reynolds-Averaged Navier–Stokes (URANS) equations, employing the Eddy Viscosity S S T   k − ω turbulence closure model. A parametric analysis is conducted to examine the variation of turbine torque coefficient with respect to the separation distance from the bluff body. Additionally, changes in turbine angular velocity, power output, and harvested energy with varying separation distances are discussed. The results indicate that even a simple Savonius wind turbine can effectively extract energy from the slipstream of a moving bluff body. A peak torque coefficient of 0.263, corresponding to a maximum power of 121.41 W, was observed at an optimal separation distance of 0.1 times the bluff body width for a motion velocity of 16.66 m/s. Furthermore, the study explores cluster arrangements of turbines, demonstrating how mutual wake interactions in parallel and oblique configurations can enhance overall energy harvesting efficiency.