The Solution for the Propagation of Sound in Cylindrical Tubes and Toroidal Waveguides with Driven Walls.

Abstract

This dissertation is a theoretical and experimental study of sound in tubes with driven (or active) walls. Two geometries are considered: (1) a cylindrical tube of infinite length, and (2) a toroidal waveguide. For sound propagation in the first geometry, two cases are theoretically considered. The first case is that of a lossless fluid, and the second is a viscous and thermally conducting fluid. The derivation of the latter case closely follows Lord Rayleigh's derivation of sound propagation in a rigid tube. Theoretical results for the particle velocity components of both cases are presented along with the three modes of propagation found in the second case. For sound propagation in the second geometry, the cases of rigid and driven wall toroids with lossless fluids are presented, along with methods for including losses in the system. Theoretical results for the pressure inside the toroid with various driving conditions and parameters are shown. Experimental measurements of the sound pressure levels in a toroid are presented and compared to theoretical results. To make some of these measurements, it was necessary to develop a device we are calling an acoustitron. Results show that the physical system is well represented by the theory presented in this work.

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Document Details

Document Type
Technical Report
Publication Date
Mar 18, 1996
Accession Number
ADA305929

Entities

People

  • Christopher C. Lawrenson
  • F. Douglas Shields

Tags

Communities of Interest

  • Advanced Electronics
  • Air Platforms
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Absorption Coefficients
  • Acoustic Waves
  • Acoustics
  • Bessel Functions
  • Differential Equations
  • Geometry
  • Laser Doppler Vibrometers
  • Measurement
  • Physics
  • Pressure Distribution
  • Pressure Measurement
  • Radial Velocity
  • Resonant Frequency
  • Standing Waves
  • Thermal Conductivity
  • Theses
  • Waveguides

Fields of Study

  • Physics

Readers

  • Combustion and Flow Dynamics.
  • Electromagnetic Wave Scattering and Antenna Radiation Engineering
  • Microwave Engineering.