Laser Generation of Sound by Nonlinear Thermal Expansion
Abstract
The two-year research effort was directed at understanding the laser generation of underwater sound at relatively low frequencies (below 1 kHz) by nonlinear expansion of the heated water. Three objectives were pursued: (1) find an upper limit for the maximum efficiency achievable; (2) solve the boundary value problem corresponding to the laser generation of sound by high-repetition rate pulsed lasers; and (3) validate some of the predictions with some experiments. Results show that the efficiency of the optoacoustic conversion process remains very small for practical naval applications in the low frequency range (below 1 kHz) even when the nonlinearity of the thermal expansion mechanism is taken into account, even with high-repetition rate high-power pulsed lasers. More suitable applications would be those where short acoustic pulses (less than a microsecond) are desirable (e.g., medical ultrasonics). Optoacoustics, Laser generated sound, Nonlinear thermal expansion.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 21, 1994
- Accession Number
- ADA276955
Entities
People
- Y. Berthelot
Organizations
- Georgia Tech