Abstract

Coherent Acoustic Scattering From Nonlinear Layers

I.Didenkulov, D.P.Alekseev, A.A.Baranov (Institute of Applied Physics, Nizhny Novgorod, Russia)

e-mail: din@hydro.appl.sci-nnov.ru

The difference-frequency scattering from a nonlinear layer was considered earlier by several authors. In the present paper more general case is studied. Two noncollinear acoustic beams of different frequencies propagating in three-layered linear acoustic medium, which characterized by density, sound velocity, and attenuation coefficient intersect in the central layer. It is supposed that the central layer has nonzero nonlinear parameter. The difference frequency scattering field is analytically calculated and then analyzed numerically. The directivity pattern of scattered field is compared to the case of unstratified medium. The coherence effects for scattering from nonlinear layers are discussed. This work was supported by RFBR (01-02-16938).

Section : 1