Hostname: page-component-cd9895bd7-gxg78 Total loading time: 0 Render date: 2024-12-26T14:30:59.922Z Has data issue: false hasContentIssue false

On turbulence and noise of an axisymmetric shear flow

Published online by Cambridge University Press:  29 March 2006

A. Michalke
Affiliation:
Institut für Thermo- und Fluiddynamik, Technische Universität, Berlin
H. V. Fuchs
Affiliation:
DFVLR-Institut für Turbulenzforschung, Berlin

Abstract

The noise produced by mean flow-turbulence interaction of a circular subsonic jet is investigated theoretically, and expanded in azimuthal constituents of the turbulent pressure fluctuations. It is found that the low-order azimuthal constituents are the most efficient sound sources. On the basis of pressure correlation measurements, the azimuthal constituents are determined in a low Mach number jet. It is found that, in a range of Strouhal numbers between 0·2 and 1, the first three to four azimuthal constituents clearly dominate over the rest of the turbulent source quantity. A strictly axisymmetric ring vortex model for the coherent structure of the turbulence is, however, shown to be inappropriate.

Type
Research Article
Copyright
© 1975 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

Arndt, R. E. A. & Nilses, A. W. 1966 On the measurement of fluctuating pressure in the mixing zone of a round jet. A.S.M.E. Publ. no. 71-FE-31.Google Scholar
Arndt, R. E. A., Tran, N. & Barefoot, G. 1972 Turbulence and acoustic characteristics of screen perturbed jets. A.I.A.A. Paper, no. 72–644.Google Scholar
Bendat, J. S. & Piersol, A. G. 1971 Random Data: Analysis and Measurement Procedures. Wiley.
Chan, Y. Y. 1974a Spatial waves in turbulent jets. Phys. Fluids, 17, 4653.Google Scholar
Chan, Y. Y. 1974b Pressure sources for a wave model of jet noise. A.I.A.A. J. 12, 241242.Google Scholar
Crow, S. C. & Champagne, F. H. 1971 Orderly structure in jet turbulence. J. Fluid Mech. 48, 547591.Google Scholar
Ffowcs Williams, J. E. 1974 Noise mechanisms. AGARD-CP-131, Tech. Eval. Rep. A 1–16.Google Scholar
Fuchs, H. V. 1970 Über die Messung von Druckschwankungen mit umströmten Mikrofonen im Freistrahl. DLR-FB, no. 70–22.Google Scholar
Fuchs, H. V. 1972a Measurement of pressure fluctuations within subsonic turbulent jets. J. Sound Vib. 22, 361378.Google Scholar
Fuchs, H. V. 1972b Space correlations of the fluctuating pressure in subsonic turbulent jets. J. Sound Vib. 23, 7799.Google Scholar
Fuchs, H. V. 1974 Resolution of turbulent jet pressure into azimuthal components. AGARD-CP-131, paper 27.Google Scholar
Jones, I. S. F. 1968 Aerodynamic noise dependent on mean shear. J. Fluid Mech. 33, 6572.Google Scholar
Lau, J. C. 1971 The coherent structure of jets. Ph.D. thesis, University of Southampton.
Lau, J. C., Fisher, M. J. & Fuchs, H. V. 1972 The intrinsic structure of turbulent jets. J. Sound Vib. 22, 379406.Google Scholar
Laufer, J., Kaplan, K. E. & Chu, W. T. 1974 On the generation of jet noise. AGARD. CP-131, paper 21.Google Scholar
Lighthill, M. J. 1952 On sound generated aerodynamically. I. General theory. Proc. Roy. Soc. A 211, 564587.Google Scholar
Lighthill, M. J. 1954 On sound generated aerodynamically. II. Turbulence as a source of sound. Proc. Roy. Soc. A 222, 132.Google Scholar
Lilley, G. M. 1958 On the noise from air jets. Aero. Res. Counc. no. 376.Google Scholar
Meecham, W. C. & Hurdle, P. M. 1974 Use of cross-correlation measurements to investigate noise generating regions of a real jet engine and a model jet. AGARD-CP-131, paper 8.Google Scholar
Michalke, A. 1970 A wave model for sound generation in circular jets. DLR-FB, no. 70–57.Google Scholar
Michalke, A. 1971 New aspects of sound generation by circular jets. Fluid Dyn. Trans. 6, 439448.Google Scholar
Michalke, A. 1972 An expansion scheme for the noise from circular jets. Z. Flugwiss. 20, 229237.Google Scholar
Michalke, A. & Fuchs, H. V. 1974 Description of turbulence and noise of an axisymmetric shear flow. DLR-FB, no. 74–50.Google Scholar
Mollo-Christensen, E. 1963 Measurements of near-field pressure of subsonic jets. AGARD Rep. no. 449.Google Scholar
Mollo-Christensen, E., Kolpin, M. A. & Martuccelli, J. R. 1964 Experiments on jet flows and jet noise far-field spectra and directivity patterns. J. Fluid Mech. 18, 285301.Google Scholar
Nagamatsu, H. T. & Sheer, R. E. 1972 Advanced fluid probe developments. AFAPL-TR-72-52, 612–716.Google Scholar
Nagamatsu, H. T., Sheer R. E. & Bigelow, E. C. 1972 Mean and fluctuating velocity contours and acoustic characteristics of subsonic and supersonic jets. A.I.A.A. Paper, no. 72–157.Google Scholar
Pao, S. P. & Lowson, M. V. 1968 Spectral technique in jet noise theory. Wyle Res. Rep. WR 68–21.Google Scholar
Ribner, H. S. 1962 Aerodynamic sound from fluid dilatations. University of Toronto, UTIA Rep. no. 86.Google Scholar
Scharton, T. D. & White, P. H. 1972 Simple pressure source model of jet noise. J. Acoust. Soc. Am. 52, 399412.Google Scholar
Scharton, T. D., White, P. H. & Rentz, P. E. 1973 Supersonic jet noise investigation using jet fluctuating pressure probes. AFAPL-TR-73-35.Google Scholar
Siddon, T. E. 1969 On the response of pressure measuring instrumentation in unsteady flow. University of Toronto, UTIAS Rep. no. 136.Google Scholar