Numerical investigation of the interaction of a vortex dipole with a deformable plate

Abstract

Energy harvesting from coherent fluid structures is a current research topic as it pertains to the design of small self-powered sensors for underwater applications. The impact of a vortex dipole with a deformable cantilevered plate at the plate tip is herein studied numerically using a strongly coupled staggered fluid-structure interaction algorithm. Three dipole Reynolds numbers, Re = 500, 1500, and 3000, are investigated for constant plate properties. As the dipole approaches the plate, positive vorticity is produced on the impact face, while negative vorticity is produced at the tip of the plate. Upon impact, the dipole splits in two and two secondary dipoles are formed. The circulation and, therefore, the trajectories of these dipoles depends on both the Reynolds number and the elasticity of the plate, and these secondary dipoles may return for subsequent impacts. While the maximum deflection of the plate does not depend significantly on Reynolds number, the plate response due to subsequent impacts of secondary dipoles does vary with Reynolds number. These results elucidate the strong interdependency between plate deformation and vortex dynamics, as well as the effect of Reynolds number on both.

Hydrodynamic impulse enhancement of a vortex ring interacting with an axisymmetric co-axial aperture

“…They found in this configuration that the dipole splits in two upon impact with the plate, with the two dipole halves then coupling with secondary boundary layer vorticity and vorticity shed from the plate tip to form two new secondary dipoles that followed curved trajectories away from the plate. Zivkov et al (2015) replaced the semi-infinite plate with a flexible plate and detailed the resulting changes in shed vorticity, which impacted the secondary dipole trajectories. In these studies, the vortex cores remained relatively undisturbed during the plate interaction by virtue of the initial vortex/plate alignment.…”

Angular momentum tearing mechanism investigation through intermolecular at the bubble interface

“…Water flow has kinetic energy which is transferred to water molecules at the interface [37,38]. The flow will turn the water molecule that is followed by dipole force turning [39].…”

On the aeroelastic energy transfer from a Lamb dipole to a flexible cantilever

“…On these topics, Priya and Inman [3], Elvin and Erturk [4], and Erturk and Inman [11] have given comprehensive reviews. Recently, another modality has received special attentions, i.e., energy transfer through FSI from coherent flow structures to deformable cantilevers [6,12,13,14,15,16]. The coherent flow structures are often modeled as vortex rings/pairs/dipoles due to their ubiquity in nature, and the cantilevers are usually placed either against or perpendicular to the vortex advection direction.…”

“…They observed that the aeroelastic efficiency varied in the range from 0.5% to 1.5%. Without considering the damping effects, Zivkov et al [14] conducted two-dimensional numerical simulations on a similar problem, but replaced the vortex ring by a Lamb dipole and assumed that the cantilever exhibited weak electromechanical coupling. They found that the aeroelastic efficiency was up to 5%.…”