QUARTERLY PROGRESS REPORT FOR THE PERIOD JANUARY, FEBRUARY, AND MARCH, 1966,

Abstract

A summary is presented of the theoretical and experimental investigation of acoustic scattering from modeled rough surfaces. Eckarts' rough scattering theory is reviewed along with the modifications of this theory with regards to the specification of a boundary condition at the surface and to a method to take into consideration shadowing at the surface by protruding anomalies at low incident grazing angles. An analytical investigation of the propagation of acoustic waves through inhomogeneous regions is presented. The applicability of the WKB approximation to the computation of propagation losses through thermoclines is examined by comparing the rigorous solution and the WKB approximation for linear index of refraction gradients. Graphs are included which allow the applicability of the WKB approximation to a particular thermocline to be determined for various gradients, frequencies and incident grazing angles. Other graphs then allow the propagation loss through the thermocline to be determined. (Author)

Document Details

Document Type
Technical Report
Publication Date
Mar 17, 1966
Accession Number
AD0654934

Entities

People

  • Aubrey L. Anderson
  • Harlan G. Frey
  • Steve K. Mitchell

Organizations

  • University of Texas at Austin

Tags

DTIC Thesaurus Topics

  • Acoustic Scattering
  • Acoustic Waves
  • Boundaries
  • Computations
  • Frequency
  • Frequency Shift
  • Grazing
  • Grazing Angles
  • Low Angles
  • Refraction
  • Refractive Index
  • Scattering
  • Specifications
  • Thermoclines

Fields of Study

  • Physics

Readers

  • Electromagnetic Wave Scattering and Antenna Radiation Engineering