Surface Impedance Modification of Plates in a Water-Filled Waveguide

Abstract

The interaction of plane waves, propagating in a water-filled cylindrical waveguide with a plate perpendicular to its axis, vith the same cross section as the tube, is determined by the surface impedance at the plate relative to the specific acoustic impedance of the medium. By means of an attached piezoelectric disk-shaped double transducer (sensor and actuator) the apparent surface impedance of the combination may, in principle, be modified to equal the impedance of the medium, thus establishing a no-reflection situation. The actuator voltage is regulated by feedback loop, based on an algorithm for complex-root finding. The analysis of this concept is given and a figure-of- merit for the transducer material is presented. Efforts to demonstrate experimentally the feasibility of this concept were inconclusive.

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Document Details

Document Type
Technical Report
Publication Date
Sep 15, 1993
Accession Number
ADA270599

Entities

People

  • Pieter S. Dubbelday

Organizations

  • United States Naval Research Laboratory

Tags

Communities of Interest

  • Advanced Electronics

DTIC Thesaurus Topics

  • Acoustic Impedance
  • Acoustic Waves
  • Acoustics
  • Actuators
  • Coaxial Cables
  • Computer Programming
  • Computer Programs
  • Computers
  • Current Density
  • Detectors
  • Measurement
  • Military Research
  • Reflection
  • Standing Waves
  • Transducers
  • Transmission Lines
  • Waveguides

Fields of Study

  • Physics

Readers

  • Electromagnetic Wave Scattering and Antenna Radiation Engineering
  • Robotics and Automation.