THEORETICAL AND EXPERIMENTAL INVESTIGATION OF CYLINDRICAL LIQUID-FILLED ACOUSTIC LENSES WITH D/LAMBDA RATIOS GREATER THAN 15.

Abstract

Focusing properties of liquid-filled cylindrical acoustic lenses are investigated theoretically and experimentally for d/lambda ratios greater than 15. A mathematical model which includes the effects of the lens shell is described and used to predict directivity patterns. Based on this model, a right-circular cylindrical lens, 40 cm in diameter, was constructed and tested at frequencies ranging from 25 to 900 khz. Agreement of experimental directivity patterns with those predicted demonstrated feasibility of the lens at d/lambda ratios up to 150, a factor of 10 greater than previously reported. Theoretical investigation indicates that for d/lambda ratios greater than 150 the elliptical cylindrical lens shows promise, but fabrication of an experimental model is yet to be undertaken. (Author)

Document Details

Document Type
Technical Report
Publication Date
Mar 01, 1968
Accession Number
AD0666542

Entities

People

  • David H. Brown
  • Donald L. Folds

Tags

DTIC Thesaurus Topics

  • Acoustic Lenses
  • Agreements
  • Diameters
  • Fabrication
  • Frequency
  • Lenses
  • Mathematical Models
  • Models

Fields of Study

  • Physics

Readers

  • Electromagnetic Wave Scattering and Antenna Radiation Engineering
  • Electronics Engineering