Hostname: page-component-cd9895bd7-jn8rn Total loading time: 0 Render date: 2024-12-22T03:03:03.997Z Has data issue: false hasContentIssue false

Resonant sound caused by flow past two plates in tandem in a duct

Published online by Cambridge University Press:  21 April 2006

S. A. T. Stoneman
Affiliation:
Department of Mechanical Engineering, University College Swansea, Singleton Park, Swansea SA2 8PP, Wales
K. Hourigan
Affiliation:
Commonwealth Scientific and Industrial Research Organisation, Division of Construction and Engineering, Highett, Victoria 3190, Australia
A. N. Stokes
Affiliation:
Commonwealth Scientific and Industrial Research Organisation, Division of Mathematics and Statistics, Clayton, Victoria 3168, Australia
M. C. Welsh
Affiliation:
Commonwealth Scientific and Industrial Research Organisation, Division of Construction and Engineering, Highett, Victoria 3190, Australia

Abstract

Two plates placed in tandem in a duct flow shed vortices, which can excite and sustain an acoustic resonance associated with the duct. The sound can in turn ‘feed back’ and ‘lock’ the vortex shedding rate to the sound frequency. The experimental conditions under which loud resonant sound is sustained are described in this paper. The acoustic sources are predicted by combining a vortex model of the flow field with a finite-element solution of the sound field, and then using Howe's theory of aerodynamic sound to calculate the energy exchange between the flow and the sound field. Only in certain regions near the plates is substantial net energy exchange possible; the direction of energy transfer depends on the spacing of the plates. The region around the trailing edge of the upstream plate is found to be always a net acoustic source during resonance, while the region around the downstream plate is a net source or sink depending on the phase of the acoustic cycle at which vortices arrive there, which in turn depends on plate spacing and flow velocity. The net source region around the downstream plate is suppressed over a wide range of plate spacings by splitting this plate at midspan and rejoining it so that one half is offset in the flow direction by the distance a vortex travels in half a sound cycle.

Type
Research Article
Copyright
© 1988 Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Abd-Rabbo, A. & Weaver D. S. 1986 A flow visualization study of flow development in a staggered tube array. J. Sound Vib. 106, 241256.Google Scholar
Archibald F. S. 1975 Self-excitation of acoustic resonances by vortex shedding. J. Sound Vib. 38, 81103.Google Scholar
Batchelor, G. K. & Townsend A. A. 1945 Singing corner vanes: a note on a peculiar double resonant sustained oscillation occurring in a wind tunnel. CSIR, Division of Aerodynamics Note 62.Google Scholar
Blevins R. D. 1985 The effect of sound on vortex shedding from cylinders. J. Fluid Mech. 61, 217237.Google Scholar
Byrne K. P. 1983 The use of porous baffles to control acoustic vibrations in crossflow tubular heat exchangers. Trans. ASME C J. Heat Transfer 105, 751758.Google Scholar
Chang, C. S. & Yeh Y.-G. 1981 A model for the analysis of air heater vibrations. ASME Paper no. 81-DET-U.Google Scholar
Chen Y. N. 1968 Flow-induced vibration and noise in tube-bank heat exchangers due to von Kármán streets. Trans. ASME B J. Engng Indust. 90, 134146.Google Scholar
Chen Y. N. 1972 Fluctuating lift forces of Kármán vortex sheets on circular cylinders and in tube bundles Trans. ASME B J. Engng Indust. 99, 623628.Google Scholar
Cowell, T. A. & Davenport C. J. 1984 Acoustic resonance in air cooled heat exchangers. First UK Natl Conf. on Heat Transfer, The Institution of Chemical Engineers Symp., Series No. 86.Google Scholar
Crighton D. G. 1981 Acoustics as a branch of fluid mechanics. J. Fluid Mech. 106, 261298.Google Scholar
Cumpsty, N. A. & Whitehead D. S. 1971 The excitation of acoustic resonances by vortex shedding. J. Sound Vib. 18, 353369.Google Scholar
Fitzpatrick J. A. 1985 The prediction of flow-induced noise in heat exchanger tube arrays. J. Sound Vib. 99, 425435.Google Scholar
Fitzpatrick, J. A. & Donaldson, I. S. 1977 A preliminary study of flow and acoustic phenomena in tube banks. Trans. ASME I J. Fluids Engng 99, 681686.Google Scholar
Howe M. S. 1984 On the absorption of sound by turbulence. IMA J. Appl. Maths 32, 187209.Google Scholar
Johnson, C. O. & Loehrke R. I. 1984 An experimental investigation of wake edge tones. AIAA J. 22, 12491253.Google Scholar
Kiya M., Sasaki, K. & Arie M. 1982 Discrete-vortex simulation of a turbulent separation bubble. J. Fluid Mech. 120, 219244.Google Scholar
Lewis R. I. 1981 Surface vorticity modelling of separated flows from two-dimensional bluff bodies of arbitrary shape. J. Mech. Engng Sci. 23, 112.Google Scholar
Morton B. R. 1984 The generation and decay of vorticity. Geophys. Astrophys. Fluid Dyn. 86, 277308.Google Scholar
Parker R. 1966 Resonance effects in wake shedding from parallel plates: experimental observations. J. Sound Vib. 4, 6272.Google Scholar
Parker R. 1967a Resonance effects in wake shedding from parallel plates: calculation of resonant frequencies. J. Sound Vib. 5, 330343.Google Scholar
Parker R. 1967b Resonance effects in wake shedding from compressor blading. J. Sound Vib. 6, 302309.Google Scholar
Parker R. 1968 An investigation of acoustic resonance effects in an axial compressor stage. J. Sound Vib. 8, 281297.Google Scholar
Parker R. 1969 Discrete frequency noise generation due to fluid flow over blades, supporting spokes and similar bodies. ASME 69-WA/GT-13.Google Scholar
Parker, R. & Pryce D. 1974 Wake excited resonances in an annular cascade: an experimental investigation. J. Sound Vib. 34, 247261.Google Scholar
Parker, R. & Stoneman S. A. T. 1984 Acoustically excited vibration of compressor blades. I. Mech. E. (UK) Third Intl Conf. on Vibrations in Rotating Machinery. York, UK.Google Scholar
Parker, R. & Stoneman S. A. T. 1985 An experimental investigation of the generation and consequences of acoustic waves in an axial flow compressor: large axial spacings between blade rows. J. Sound Vib. 99, 169182.Google Scholar
Parker R., Stoneman, S. A. T. & Carr M. 1984 Excitation of blade vibration by flow induced acoustic resonances in axial flow compressors. Unsteady Aerodynamics of Turbomachines and Propellers. Jesus College, Cambridge.Google Scholar
Rockwell D. 1982 Oscillations of impinging shear layers. Invited lecture, 20th Aerospace Sciences Meeting, AIAA-82–0047,Google Scholar
Rockwell, D. & Naudascher E. 1979 Self-sustained oscillations of impinging free shear layers. Ann. Rev. Fluid Mech. 11, 6794.Google Scholar
Stokes, A. N. & Welsh M. C. 1986 Flow-resonant sound interaction in a duct containing a plate. Part II. Square leading edge. J. Sound Vib. 104, 5573.Google Scholar
Stoneman S. A. T. 1984 An experimental investigation of flow excited acoustic fields in an axial flow compressor. Ph.D. thesis, University College of Swansea.
Welsh, M. C. & Gibson D. C. 1979 Interaction of induced sound with flow past a square leading edge plate in a duct. J. Sound Vib. 67, 501511.Google Scholar
Welsh, M. C. & Stokes A. N. 1986 Transient vortex modelling of flow induced acoustic resonances near cavities or obstructions in ducts. In Proc. IUTAM Symp. on Aero and Hydro-acoustics, Lyons, pp. 499505. Springer.
Welsh M. C., Stokes, A. N. & Parker R. 1984 Flow-resonant sound interaction in a duct containing a plate. Part I. Semicircular leading edge. J. Sound Vib. 95, 305323.Google Scholar
Zdravkovich, M. M. & Nuttall J. A. 1974 On the elimination of aerodynamic noise in a staggered tube bank. J. Sound Vib. 34, 173177.Google Scholar