Bubble Production by Breaking Waves
Abstract
It has been shown (Medwin and Beaky, (1989)) that spilling breakers in the laboratory produce a sound close to the Knudsen sea surface noise spectrum from 400 Hz to 20 kHz. The surface spectral production density of newly-created near surface bubbles under these laboratory spilling breakers has now been acoustically determined by using an array of hydrophones. The surface spectral density has been obtained by identifying the individual bubbles that create this noise spectrum. The radii were calculated from the resonance frequencies. The bubble positions on the surface of the water were determined from the difference in time of arrival of the bubble radiation to the elements of two vertical arrays of hydrophones. The production area and rate of production of bubbles of radii 0.048 to 7.40 millimeters have been calculated and the total volume of air encapsulated into bubble foam per unit area of spilling breakers has been determined. Keywords: Bubble production density; Underwater acoustics. Theses.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1989
- Accession Number
- ADA221714
Entities
People
- Albert C. Daniel Jr.
Organizations
- Naval Postgraduate School