Transmission of a Narrow Beam of Sound across the Boundary between Two Fluids
In studying shallow penetration of acoustic waves into saturated marine sediments, narrow beams of sound (at kHz frequencies) have been used under controlled conditions, (Muir, Horton, and Thompson. J. Sound & Vibration, 64, June 1979). In order to contribute to the understanding of the physical basis of the penetration of sound across the boundary, a model experiment was devised at a frequency of about 1 Mhz, using two non-mixing liquids. This paper presents the experimental results obtained and compares these results with a theoretical development. The theory developed also provides a means of understanding some of the effects observed by Muir and co-workers when a parametric source was used for penetration into a saturated sediment.
KeywordsTransit Time Total Internal Reflection Beam Pattern Grazing Angle Narrow Beam
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