Accession Number : ADA133660

Title :   Parametric Acoustic Array Formation via Weak Collinear and Noncollinear Interaction in Dispersive Fluids.

Descriptive Note : Final rept. 1 Aug 79-30 Sep 83,

Corporate Author : PENNSYLVANIA STATE UNIV UNIVERSITY PARK

Personal Author(s) : Maynard,Julian D

PDF Url : ADA133660

Report Date : Sep 1983

Pagination or Media Count : 12

Abstract : This final report contains a historical review of the technical and administrative highlights of the research project. Briefly, the project was a theoretical investigation of the effects of dispersion on the nonlinear formation of a difference-frequency beam from two primary beams. The approach involved both analytical and numerical solutions to the nonlinear and dispersive paraxial wave equation with emphasis on Guassian beam solutions. In the case of collinear primary beams, known results were reproduced, but with some siginificant errors corrected. Noncollinear interaction of finite width beams was investigated for the first time in this project. Some unexpected results were discovered in this case: it was found that the finite beam width caused the difference beam to have directivity maximum near the axis of the primaries, rather than in the direction of the primary wave-vector difference, and decreased the conversion efficiency to significantly below the plane-wave efficiency. Further research in this area is indicated.

Descriptors :   *Acoustic arrays, *Dispersions, *Interactions, *Fluids, Parametric devices, Wave equations, Beams(Radiation), Plane waves, Efficiency, Low strength, Gaussian quadrature, Parameters

Subject Categories : Electrical and Electronic Equipment
      Acoustic Detection and Detectors

Distribution Statement : APPROVED FOR PUBLIC RELEASE