Accession Number : ADA194354

Title :   Nonlinear Optoacoustic Underwater Sound.

Descriptive Note : Final rept. 1 Feb 86-31 Jul 87,

Corporate Author : TEXAS UNIV AT AUSTIN APPLIED RESEARCH LABS

Personal Author(s) : Chotiros, Nicholas P

PDF Url : ADA194354

Report Date : 11 Jan 1988

Pagination or Media Count : 152

Abstract : The objective of this study is to investigate nonlinear optoacoustic generation processes. The initiative for this project arose out of the findings from a previous ONR funded project on the thermoacoustic sound source. A new theoretical model was developed, called the equilibrium blast model, which is based on the hydrodynamic equations of equilibrium. The conditions at the shock fronts are determined by the maximum entropy condition. The distribution of energy within the blast is assumed to be through thermal conduction. Experiments were carried out to test the model, and the model was also compared with experimental data. The experimental data showed that more than one process was involved. So far, three distinct blast processes have been identified, the weak blast, the thermal conduction limited equilibrium blast, and the emission limited equilibrium blast. The last is deserving of further study from a basic physics point of view and from an application standpoint.

Descriptors :   *UNDERWATER SOUND, *LASER BEAMS, ACOUSTIC ARRAYS, BLAST, DISTRIBUTION, EMISSION, ENERGY, ENTROPY, EQUATIONS, EQUILIBRIUM(GENERAL), EXPERIMENTAL DATA, HYDRODYNAMICS, LOW STRENGTH, MODELS, PHYSICS, PROTOTYPES, SOUND GENERATORS, THERMAL CONDUCTIVITY, THERMODYNAMICS, LASER APPLICATIONS, WATER, INTERACTIONS, THEORY

Subject Categories : Acoustics

Distribution Statement : APPROVED FOR PUBLIC RELEASE