Prediction of the acoustic field due to a point source over a porous layer

2009 ◽  
Vol 125 (4) ◽  
pp. 1864-1867 ◽  
Author(s):  
Jean F. Allard
Keyword(s):  
Point Source ◽  
Acoustic Field ◽  
Porous Layer

High-Frequency Diffraction of a Point Source Field by a Strongly Elongated Elliptic Cylinder

2019 ◽  
Vol 105 (6) ◽  
pp. 912-917
Author(s):  
Ivan V. Andronov
Keyword(s):  
Point Source ◽  
Cross Section ◽  
Acoustic Field ◽  
High Frequency ◽  
Elliptic Cylinder ◽  
Linear Source ◽  
Source Field ◽  
Major Semiaxis

The problem of diffraction of a high-frequency point source acoustic field by an infinite elliptic cylinder with a strongly elongated cross-section is studied. At every direction of propagation, the solution is shown to be similar to those of a linear source field diffraction by a cylinder with correspondingly enlarged major semiaxis.

Impact of point source on fissured poroelastic medium: Green’s function approach

2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Shishir Gupta ◽  
Soumik Das ◽  
Rachaita Dutta
Keyword(s):  
Point Source ◽  
Green’S Function ◽  
Half Space ◽  
Porous Layer ◽  
Green's Function ◽  
Anisotropic Fluid ◽  
Complex Frequency ◽  
Sh Wave ◽  
Content Type ◽  
Porous Half Space

Purpose The purpose of this paper is to investigate the mathematical model comprising a heterogeneous fluid-saturated fissured porous layer overlying a non-homogeneous anisotropic fluid-saturated porous half-space without fissures. The influence of point source on horizontally polarized shear-wave (SH-wave) propagation has been studied intensely. Design/methodology/approach Techniques of Green’s function and Fourier transform are applied to acquire displacement components, and with the help of boundary conditions, complex frequency equation has been constructed. Findings Complex frequency relation leads to two distinct equations featuring dispersion and attenuation properties of SH-wave in a heterogeneous fissured porous medium. Using MATHEMATICA software, dispersion and damping curves are sketched to disclose the effects of heterogeneity parameters associated with both media, parameters related to rigidity and density of single porous half-space, attenuation coefficient, wave velocity, total porosity, volume fraction of fissures and anisotropy. The fact of obtaining classical Love wave equation by introducing several particular conditions establishes the validation of the considered model. Originality/value To the best of the authors’ knowledge, effect of point source on SH-wave propagating in porous layer containing macro as well as micro porosity is not analysed so far, although theory of fissured poroelasticity itself has vast applications in real life and impact of point source not only enhances the importance of fissured porous materials but also opens a new area for future research.

The radiated fields of multipole point sources near a solid spherical surface

1970 ◽  
Vol 43 (3) ◽  
pp. 597-606 ◽  
Author(s):  
Huw G. Davies
Keyword(s):  
Point Source ◽  
Acoustic Field ◽  
Scattered Field ◽  
Spherical Surface ◽  
Solid Sphere ◽  
Incident Field ◽  
Point Sources ◽  
Low Frequencies ◽  
High Frequencies

The acoustic field radiated by a multipole point source positioned near to the surface of a solid sphere is calculated at both low and high frequencies. It is shown that the scattered field at low frequencies is always dipole, but at high frequencies is of the same type as the incident field. The application of the results to the acoustic field radiated by turbulence near a sphere is briefly discussed.

Sign in / Sign up

Export Citation Format

Share Document