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Diffraction by a hard half-plane: Useful approximations to an exact formulation

Ouis, Djamel LU (2002) In Journal of Sound and Vibration 252(2). p.191-221
Abstract
in this paper, the problem of diffraction of a spherical wave by a hard half-plane is considered. The starting point is the Biot-Tolstoy theory of diffraction of a spherical wave by a fluid wedge with hard boundaries. In this theory, the field at a point in the fluid is composed eventually of a geometrical part: i.e., a direct component, one or two components due to the reflections on the sides of the hard wedge, and a diffracted component due exclusively to the presence of the edge of the wedge. The mathematical expression of this latter component has originally been given in an explicit closed form for the case of a unit momentum wave incidence, but Medwin has further developed its expression for the more useful case of a Dirac delta... (More)
in this paper, the problem of diffraction of a spherical wave by a hard half-plane is considered. The starting point is the Biot-Tolstoy theory of diffraction of a spherical wave by a fluid wedge with hard boundaries. In this theory, the field at a point in the fluid is composed eventually of a geometrical part: i.e., a direct component, one or two components due to the reflections on the sides of the hard wedge, and a diffracted component due exclusively to the presence of the edge of the wedge. The mathematical expression of this latter component has originally been given in an explicit closed form for the case of a unit momentum wave incidence, but Medwin has further developed its expression for the more useful case of a Dirac delta point excitation. The expression of this form is given in the time domain, but it is quite difficult to find exactly its Fourier transform for studying the frequency behaviour of the diffracted field. It is thus the aim of this paper to present various useful approximations of the exact expression. Among the approximations treated, three are most accurate for engineering purposes, and one of them is proposed. for its simplicity, as appropriate for most occurring practical situations. (C) 2002 Elsevier Science Ltd. (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Journal of Sound and Vibration
volume
252
issue
2
pages
191 - 221
publisher
Elsevier
external identifiers
  • wos:000175766300001
  • scopus:0037172180
ISSN
0022-460X
DOI
10.1006/jsvi.2000.3553
language
English
LU publication?
yes
id
0e2cd319-a781-42ba-86d6-fcd5a46afd5c (old id 337137)
date added to LUP
2007-11-08 09:04:44
date last changed
2017-01-01 07:04:09
@article{0e2cd319-a781-42ba-86d6-fcd5a46afd5c,
  abstract     = {in this paper, the problem of diffraction of a spherical wave by a hard half-plane is considered. The starting point is the Biot-Tolstoy theory of diffraction of a spherical wave by a fluid wedge with hard boundaries. In this theory, the field at a point in the fluid is composed eventually of a geometrical part: i.e., a direct component, one or two components due to the reflections on the sides of the hard wedge, and a diffracted component due exclusively to the presence of the edge of the wedge. The mathematical expression of this latter component has originally been given in an explicit closed form for the case of a unit momentum wave incidence, but Medwin has further developed its expression for the more useful case of a Dirac delta point excitation. The expression of this form is given in the time domain, but it is quite difficult to find exactly its Fourier transform for studying the frequency behaviour of the diffracted field. It is thus the aim of this paper to present various useful approximations of the exact expression. Among the approximations treated, three are most accurate for engineering purposes, and one of them is proposed. for its simplicity, as appropriate for most occurring practical situations. (C) 2002 Elsevier Science Ltd.},
  author       = {Ouis, Djamel},
  issn         = {0022-460X},
  language     = {eng},
  number       = {2},
  pages        = {191--221},
  publisher    = {Elsevier},
  series       = {Journal of Sound and Vibration},
  title        = {Diffraction by a hard half-plane: Useful approximations to an exact formulation},
  url          = {http://dx.doi.org/10.1006/jsvi.2000.3553},
  volume       = {252},
  year         = {2002},
}