3D acoustic scattering from an irregular fluid waveguide via the BEM.

*(English)*Zbl 0982.76067Summary: We use the BEM to calculate the variation in the pressure field generated by a dilatational point load inside a channel filled with a homogeneous fluid, in the presence of an irregular floor. The Green’s functions are defined in the frequency domain and obtained by superposing virtual acoustic sources combined so as to generate the boundary conditions on free rigid surfaces of the channel. The responses in time domain are obtained by means of Fourier transforms, making use of complex frequencies. The main features and spectral representation of the signals scattered by irregular floors are then described and used to elucidate the most important aspect of wave acoustics, which can provide the basis for the development of non-destructive testing and imaging methods.

##### MSC:

76M15 | Boundary element methods applied to problems in fluid mechanics |

76Q05 | Hydro- and aero-acoustics |

##### Keywords:

acoustic scattering; irregular fluid waveguide; channel filled with homogeneous fluid; dilatational point load; irregular floor; Green’s function; frequency domain; virtual acoustic source; boundary conditions; time domain; Fourier transform; complex frequencies
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\textit{L. Godinho} et al., Eng. Anal. Bound. Elem. 25, No. 6, 443--453 (2001; Zbl 0982.76067)

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