Numerical study of the effect of periodic jet excitation on cylinder aerodynamic instability

Shinji Hiejima, T. Nomura

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

Numerical simulations based on the ALE finite element method are carried out to examine the aerodynamics of an oscillating circular cylinder when the separated shear flows around the cylinder are stimulated by periodic jet excitation with a shear layer instability frequency. The excitation is applied to the flows from two points on the cylinder surface. The numerical results showed that the excitation with a shear layer instability frequency can reduce the negative damping and thereby stabilize the aerodynamics of the oscillating cylinder. The change of the lift phase seems important in stabilizing the cylinder aerodynamics. The change of lift phase is caused by the merger of the vortices induced by the periodic excitation with a shear layer instability frequency, and the vortex merging comes from the high growth rate, the rapid increase of wave number and decrease of phase velocity for the periodic excitation in the separated shear flows.

Original languageEnglish
Pages (from-to)141-150
Number of pages10
JournalWind and Structures, An International Journal
Volume5
Issue number2-4
Publication statusPublished - Mar 2002

Fingerprint

Aerodynamics
Numerical Study
Excitation
Shear flow
Vortex flow
Oscillating cylinders
Shear Flow
Phase velocity
Circular cylinders
Vortex
Merging
ALE Method
Damping
Mergers
Phase Velocity
Finite element method
Circular Cylinder
Computer simulation
Finite Element Method
Numerical Simulation

Keywords

  • Aerodynamic instability
  • ALE
  • Circular cylinder
  • Finite element method
  • Periodic excitation
  • Separated shear layer
  • Shear layer instability
  • Vortex-induced vibration

ASJC Scopus subject areas

  • Renewable Energy, Sustainability and the Environment
  • Civil and Structural Engineering
  • Computational Mechanics
  • Mechanics of Materials
  • Building and Construction

Cite this

Numerical study of the effect of periodic jet excitation on cylinder aerodynamic instability. / Hiejima, Shinji; Nomura, T.

In: Wind and Structures, An International Journal, Vol. 5, No. 2-4, 03.2002, p. 141-150.

Research output: Contribution to journalArticle

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