Effect of Cylinder Location inside a Rectangular Duct on the Excitation Mechanism of Acoustic Resonance

Authors

  • Nadim Arafa University of Ontario Institute of Technology
  • Ahmed Tariq University of Ontario Institute of Technology
  • Atef Mohany University of Ontario Institute of Technology
  • Marwan Hassan University of Guelph

Keywords:

Aeroacoustics, Flow-excited Acoustic Resonance,

Abstract

The flow-sound interaction mechanism of a single cylinder in cross-flow is investigated experimentally. The cylinder is located at different vertical locations inside a rectangular duct in order to investigate the effect of the cylinder location on the excitation mechanism of acoustic resonance. During the tests, the acoustic cross-modes of the duct housing the cylinder are self-excited. It is found that the cylinder location affects the process of the flow-excited acoustic resonance and the levels of the generated acoustic pressure. The resonance of a specific acoustic cross-mode is excited when the cylinder is located at the acoustic pressure node, or the acoustic particle velocity anti-node, of that acoustic cross-mode. However, when the cylinder is shifted away from the pressure node of a certain acoustic cross-mode, a combination of cross-modes is excited and their intensity seems to be proportional to the ratio of the acoustic particle velocities of these modes at the cylinder’s location. Moreover, as the cylinder moves closer to the top wall of the rectangular duct, the Strouhal number value decreases due to the interference between the wake of the cylinder and the duct wall. Therefore, the onset of acoustic resonance for this case occurs at a higher value of reduced flow velocity.

Author Biographies

Nadim Arafa, University of Ontario Institute of Technology

PhD Candidate.
AeroAcoustics and Noise Control Laboratory, Faculty of Engineering and Applied Science, University of Ontario Institute of Technology.

Ahmed Tariq, University of Ontario Institute of Technology

Undergraduate Research Assistant

AeroAcoustics and Noise Control Laboratory, Faculty of Engineering and Applied Science, University of Ontario Institute of Technology.

Atef Mohany, University of Ontario Institute of Technology

Assistant Professor

AeroAcoustics and Noise Control Laboratory

Faculty of Engineering and Applied Science

University of Ontario Institute of Technology

Marwan Hassan, University of Guelph

Assistant Professor

School of Engineering, University of Guelph, ON, Canada

Published

2014-03-01

How to Cite

1.
Arafa N, Tariq A, Mohany A, Hassan M. Effect of Cylinder Location inside a Rectangular Duct on the Excitation Mechanism of Acoustic Resonance. Canadian Acoustics [Internet]. 2014Mar.1 [cited 2021Jun.22];42(1):33-40. Available from: https://jcaa.caa-aca.ca/index.php/jcaa/article/view/2609

Issue

Section

Article - Aeroacoustics