Accession Number : AD0869673

Title :   Sound Propagation Study.

Descriptive Note : Final rept.,

Corporate Author : RAYTHEON CO NEW LONDON CT MARINE RESEARCH LAB

Personal Author(s) : Chamberlain, Stanley G.

Report Date : 31 MAR 1970

Pagination or Media Count : 116

Abstract : The Fast Field Program (FFP) is a numerical method of evaluating the exact solution of the acoustical wave equation. Modern numerical techniques, such as the Fast Fourier Transform and a generalization of this, the Chirp Fourier Transform, make possible the direct integration of wave solutions expressed in certain integral forms. Two formulations for harmonic point sources in layered inhomogeneous media are developed. These include a general numerical method which allows arbitrary velocity profiles that need not be approximated by analytic functions nor divided into layers, and which permit wave field computations as functions of both range and depth. Extensions are developed for spatially distributed sources and for velocity profiles and boundary conditions which vary in range.

Descriptors :   (*HYDRODYNAMICS, SOUND TRANSMISSION), (*SOUND TRANSMISSION, NUMERICAL ANALYSIS), UNDERWATER SOUND, INTEGRAL TRANSFORMS, WAVE FUNCTIONS, BOUNDARY VALUE PROBLEMS, BESSEL FUNCTIONS, PROPAGATION.

Subject Categories : Acoustics
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE