Sound Propagation over Multiple Wedges and Barriers

  • Kim, Hyun-Sil (Acoustics Laboratory Korea Institute of Machinery and Materials) ;
  • Kim, Jae-Sueng (Acoustics Laboratory Korea Institute of Machinery and Materials) ;
  • Kang, Hyun-Ju (Acoustics Laboratory Korea Institute of Machinery and Materials) ;
  • Kim, Bong-Ki (Acoustics Laboratory Korea Institute of Machinery and Materials) ;
  • Kim, Sang-Ryul (Acoustics Laboratory Korea Institute of Machinery and Materials)
  • Published : 2004.06.01

Abstract

A theoretical formula that is based on the geometrical theory of diffraction (GTD) is proposed for computing sound diffraction by multiple wedges, barriers, and polygonal-like shapes. The formula can treat both convex and concave edges, where edges mayor may not be inter-connected. Comparisons of theoretical predictions with other results done by the BEM or experiments for scaled model confirm the accuracy of the present formula. Numerical examples such as double wedges and doubly inclined barrier show that when there exist several diffraction paths for given source and receiver positions, the insertion loss is dominated by the diffraction associated with the shortest propagation path.

Keywords

References

  1. D. Ouis, 'Noise attenuation by a hard wedge shaped barrier', Journal of Sound and Vibration, 262, 347-364, 2003 https://doi.org/10.1016/S0022-460X(02)01134-3
  2. R. G. Kouyoumjian and P. H. Pathak, 'A uniform geometrical theory of diffraction for an edge in a perfectly conducting surface', Proceedings of the IEEE, 62, 1448-1461, 1974 https://doi.org/10.1109/PROC.1974.9651
  3. A. D. Pierce, 'Diffraction of sound around corners and over wide barriers', Journal of the Acoustical Society of America, 55, 941-955, 1974 https://doi.org/10.1121/1.1914668
  4. W. T. Hadden and A. D. Pierce, 'Sound diffraction around screens and wedges for arbitrary point source locations', Journal of the Acoustical Society of America, 69, 1266-1276, 1981, Erratum, 71, 1290, 1982 https://doi.org/10.1121/1.385809
  5. E. M. Salomons, 'Sound propagation in complex outdoor situations with a non-refracting atmosphere: model based on analytical solutions for diffraction and reflection', Acustica, 83, 436-454, 1997
  6. T. Kawai, 'Sound diffraction by a many-sided barrier or pillar', Journal of Sound and Vibration, 79, 229-242, 1980
  7. Byung-Joo Jin, Hyun-Sil Kim, Hyun-Ju Kang, and Jae-Seung Kim, 'Sound diffraction by a partially inclined noise barrier', Applied Acoustics, 62,1107-1121, 2000 https://doi.org/10.1016/S0003-682X(00)00094-3
  8. J. S. Robertson, 'Sound propagation over a large wedge: a comparison between the geometrical theory of diffraction and the parabolic equation', Journal of the Acoustical Society of America, 106, 113-119, 1999 https://doi.org/10.1121/1.427040
  9. G. J. Wadsworth and J. p. Chambers, 'Scale model experiments on the insertion loss of wide and double barriers', Journal of the Acoustical Society of America, 107, 2344-2350, 2000 https://doi.org/10.1121/1.428620
  10. M. A. Biot and I. Tolstoy, 'Formulation of wave propagation in infinite media by normal coordinates with an application to diffraction', Journal of the Acoustical Society of America, 29, 381-391, 1957 https://doi.org/10.1121/1.1908899
  11. K. Higashi, Y. M. Park, K. Takagi, R. Hotta, and K. Yamamoto, 'Noise attenuation by triple barriers', Proceeding of Technical Presentation of Noise Control in Japan (in Japanese), 297-300, 1995