Aeroacoustic source characterization technique applied to a cylindrical Helmholtz resonator
Citation:
Francisco Rodriguez Verdugo, Roberto Camussi, Gareth J. Bennett, Aeroacoustic source characterization technique applied to a cylindrical Helmholtz resonator, 18th International Congress on Sound and Vibration (ICSV18), Rio de Janeiro, Brazil, 10-14 July, Paper No. 2062, 2011, 349 - 356Download Item:
Abstract:
The aim of this work is to investigate the sound produced by a Helmholtz resonator excited
by a boundary layer. A deep cylindrical cavity with a small rectangular opening was designed
to allow Helmholtz resonance as well as longitudinal and azimuthal acoustic modes within
the cavity to be excited by varying the wind tunnel flow speed. Experiments performed show
how lock-on between each of these three acoustic resonances and the shear layer hydrodynamic
modes can been generated. The pressure measured by means of a microphone flush
mounted with the internal surface of the cavity wall is used to phase-average the planar Particle
Image Velocimetry (PIV) data in the shear layer region. The acoustic energy generated is
calculated by applying the vortex sound theory developed by Powell and modified by Howe
for its application to wall bounded flows. Practically, this can be achieved by extracting the
flow velocity and vorticity the from the PIV data and by computing numerically the acoustic
particle velocity field. The acoustic sources are localised in space and quantified over an
acoustic period providing insight into the sound production of flow-excited cylindrical cavities.
Author's Homepage:
http://people.tcd.ie/bennettgDescription:
PUBLISHEDRio de Janeiro, Brazil
Author: Bennett, Gareth
Other Titles:
18th International Congress on Sound and Vibration (ICSV18)Type of material:
Conference PaperSeries/Report no:
Paper No. 2062Availability:
Full text availableKeywords:
Cavity Noise, Helmholtz Resonator, Howe's Analogy, Aeroacoustics, Azimuthal Radial Acoustic Modes, Duct Acoustics, Modal Decomposition, Particle Image Velocimetry (PIV)Subject (TCD):
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