Flow-induced motions of flexible plates: Fluttering, twisting and orbital modes

Yaqing Jin, Jin Tae Kim, Shifeng Fu, Leonardo Patricio Chamorro Chavez

Research output: Contribution to journalArticle

Abstract

The unsteady dynamics of wall-mounted flexible plates under inclined flows was fundamentally described using theoretical arguments and experiments under various Cauchy numbers (where is the fluid density, and are the plate width and length, is the incoming velocity, is Young's modulus and is the second moment of the area) and inclination angles . Three-dimensional particle tracking velocimetry and a high-resolution force sensor were used to characterize the evolution of the plate dynamics and aerodynamic force. We show the existence of three distinctive, dominant modes of tip oscillations, which are modulated by the structure dynamic and flow instability. The first mode is characterized by small-amplitude, planar fluttering-like motions occurring under a critical Cauchy number, . Past this condition, the motions are dominated by the second mode consisting of unsteady twisting superimposed onto the fluttering patterns. The onset of this mode is characterized by a sharp increase of the force fluctuation intensity. At sufficiently high and , the plate may undergo a third mode given by large-scale tip orbits about the mean bending. Using the equation of motion and first-order approximations, we propose a formulation to estimate as a function of ; it exhibits solid agreement with experiments.

Original languageEnglish (US)
Pages (from-to)273-285
Number of pages13
JournalJournal of Fluid Mechanics
Volume864
DOIs
StatePublished - Apr 10 2019

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twisting
orbitals
Velocity measurement
Equations of motion
Aerodynamics
Orbits
aerodynamic forces
Elastic moduli
Experiments
Fluids
Sensors
inclination
modulus of elasticity
equations of motion
orbits
moments
formulations
oscillations
fluids
high resolution

Keywords

  • Flow-structure interactions

ASJC Scopus subject areas

  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering

Cite this

Flow-induced motions of flexible plates : Fluttering, twisting and orbital modes. / Jin, Yaqing; Kim, Jin Tae; Fu, Shifeng; Chamorro Chavez, Leonardo Patricio.

In: Journal of Fluid Mechanics, Vol. 864, 10.04.2019, p. 273-285.

Research output: Contribution to journalArticle

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