Vortex-induced energy harvesting of an elliptic blade in high-Reynolds lid-driven cavity flow
الموضوعات : Analytical and Numerical Methods in Mechanical Design
Ali Akbar Hosseinjani
1
(
Department of Mechanical Engineering, Qazvin Branch, Islamic Azad University, Qazvin, Iran.
)
Ghasem Akbari
2
(
Department of Mechanical Engineering, Qazvin Branch, Islamic Azad University, Qazvin, Iran.
)
الکلمات المفتاحية: Lid-driven cavity flow is characterized by large-scale energetic eddies which are potential for energy harvesting purposes. The present article deals with numerical study of vortex-induced autorotation of an elliptic blade hinged at the center of a l, clockwise autorotation and counter-clockwise autorotation are three dominant modes observed at various configurations and different temporal stages. The average-length blade is equally characterized by vortices at both directions, and consequently experiences a fluttering mode. In contrast, short (long) bladeis mainly affected by one dominant vortex type, leading to steady autorotation in counter-clockwise (clockwise) direction. At stable autorotation of blade in both directions, regular cyclic temporal oscillations are observed in the rotational speed, which are due to cyclic evolution of the near-blade vortices and their alternating moment applied to the blade,
ملخص المقالة :
Lid-driven cavity flow is characterized by large-scale energetic eddies which are potential for energy harvesting purposes. The present article deals with numerical study of vortex-induced autorotation of an elliptic blade hinged at the center of a lid-driven cavity.Immersed boundary method is utilized to solve the governing equations for this moving boundary problem. Four different blade dimensions are considered at a fairly high-Reynolds number to evaluate the impact of various vortex types and flow unsteadiness on the blade dynamics. Small-amplitude fluttering, clockwise autorotation and counter-clockwise autorotation are three dominant modes observed at various configurations and different temporal stages. The average-length blade is equally characterized by vortices at both directions, and consequently experiences a fluttering mode. In contrast, short (long) bladeis mainly affected by one dominant vortex type, leading to steady autorotation in counter-clockwise (clockwise) direction. At stable autorotation of blade in both directions, regular cyclic temporal oscillations are observed in the rotational speed, which are due to cyclic evolution of the near-blade vortices and their alternating moment applied to the blade.