Sound propagation over inhomogeneous ground including a sound velocity profile
2006 (English)In: Mathematical Modeling of Wave Phenomena / [ed] Nilsson, B; Fishman, L, MELVILLE, NY: AMER INST PHYSICS , 2006, Vol. 834, 122-129 p.Conference paper (Refereed)
The atmospheric profile whose sound speed varies linearly with height is simple in concept, but leads to complications when solving for the sound pressure. Its effects are commonly approximated by a similar profile whose squared refractive index is a linear function of height. In this paper, the validity of the approximation has been examined for sound propagation above an impedance ground and a computational approximation is given. The method relies upon a family of radiation boundary conditions for the wave equation derived by truncating a summation function approximation of a corresponding plane wave reflection coefficient representation. It is demonstrated bow these boundary conditions can be formulated in terms of a finite element approach. Numerical examples illustrate results with four coefficients included at the upper fictitious boundary conditions for the case of sound propagation above a grass-strip and sound propagation over the grass-strip with an atmospheric profile.
Place, publisher, year, edition, pages
MELVILLE, NY: AMER INST PHYSICS , 2006. Vol. 834, 122-129 p.
, AIP CONFERENCE PROCEEDINGS, ISSN 0094-243X ; 834
non-reflecting boundary conditions, sound propagation, finite elements
Physical Sciences Fluid Mechanics and Acoustics
IdentifiersURN: urn:nbn:se:kth:diva-41954DOI: 10.1063/1.2205795ISI: 000237610000012ScopusID: 2-s2.0-33845572249ISBN: 0-7354-0325-2OAI: oai:DiVA.org:kth-41954DiVA: diva2:445788
Conference: 2nd Conference on Mathematical Modeling of Wave Phenomena. Vaxjo, SWEDEN. AUG 14-19, 2005
QC 201110052011-10-052011-10-042016-05-11Bibliographically approved