Laboratory measurement of noise generation by shoaling breakers

Abstract

Simultaneous measurements of the surface gravity wave field and the generated acoustic spectra were made in a sandy beached wave tank. A video camera captured the evolution of the breaking waves. Generated acoustic power levels as a function of the wave crest slope and frequency are presented. An empirical model relating the acoustic energy to the measured wave crest slope for different surface wave frequencies is developed based on a linear regression. It is determined that the wave crest slope is a good predictor of generated acoustic energies. [Work supported by ONR base funding at NRL.]