The Moving Thermoacoustic Array: A Theoretical Feasibility Study
Abstract
A theoretical study of the feasibility of the moving thermoacoustic source as a sound projector in underwater acoustic applications is presented. Since the Doppler shift is direction dependent, it was found that the moving optoacoustic sources are potentially useful for direction finding by virtue of the extremely high Doppler shifts achievable. While the thermoacoustic array has certain advantages over conventional acoustic projectors, notably the noncontact property and the Doppler direction finding capability, its optoacoustic energy conversion efficiency is no better than that of the stationary thermoacoustic array. This conclusion was arrived at through mathematical analysis from basic principles, and supported by computer generated numerical examples. The conversion efficiency was found to be strongly dependent on the acoustic signal carrier frequency and on the optical signal waveform. It was found that the thermoacoustic conversion was most efficient when the optical energy was delivered as an impulse train. The efficiency is fundamentally limited by the physical properties of the medium, particularly the coefficient of thermal expansion and the specific heat. A different optoacoustic conversion process, which employs nonlinear physical reactions to generate sound, is being pursued. (Author).
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 17, 1985
- Accession Number
- ADA154510
Entities
People
- Nicholas P. Chotiros
Organizations
- University of Texas at Austin