Efficient calculation of twodimensional periodic and waveguide acoustic Green's functions.
Publication date
20090706T13:08:37ZKeyword
IntegrationAcoustic wave propagation,
Acoustic wave scattering
Green's function methods
Acoustic waveguides
Acoustic field
Atmospheric acoustics
Boundaryelements methods
Laplace transforms
Acoustic radiators
Acoustic impedance
PeerReviewed
Yes
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New representations and efficient calculation methods are derived for the problem of propagation from an infinite regularly spaced array of coherent line sources above a homogeneous impedance plane, and for the Green's function for sound propagation in the canyon formed by two infinitely high, parallel rigid or sound soft walls and an impedance ground surface. The infinite sum of source contributions is replaced by a finite sum and the remainder is expressed as a Laplacetype integral. A pole subtraction technique is used to remove poles in the integrand which lie near the path of integration, obtaining a smooth integrand, more suitable for numerical integration, and a specific numerical integration method is proposed. Numerical experiments show highly accurate results across the frequency spectrum for a range of ground surface types. It is expected that the methods proposed will prove useful in boundary element modeling of noise propagation in canyon streets and in ducts, and for problems of scattering by periodic surfaces.Version
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Horoshenko, K.V. and ChandlerWilde, S.N. (2002). Efficient calculation of twodimensional periodic and waveguide acoustic Green's functions. The Journal of the Acoustical Society of America. Vol. 111, No. 4, pp. 16101622.Link to publisher’s version
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