Abstract
When low frequency sound interacts with a low roughness rigid surface at grazing or near-grazing angles, a coherent boundary wave is generated by repeated forward scatter. The boundary wave extends several wavelengths into the fluid and affects both the phase velocity and the amplitude of the forward propagating sound near the surface. The propagation is subsonic and slightly dispersive and, under certain conditions, the reflection coefficient can be greater than unity. Laboratory model results for periodic roughness elements have now been extended to demonstrate that these boundary wave phenomena are significant for steep sloped randomly rough surfaces. Predictions are made of the consequences of boundary wave propagation at a rough rigid ocean bottom.
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© 1986 Plenum Press, New York
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Medwin, H. (1986). Near Grazing Propagation over a Low Roughness Hard Ocean Bottom. In: Akal, T., Berkson, J.M. (eds) Ocean Seismo-Acoustics. NATO Conference Series, vol 16. Springer, Boston, MA. https://doi.org/10.1007/978-1-4613-2201-6_36
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DOI: https://doi.org/10.1007/978-1-4613-2201-6_36
Publisher Name: Springer, Boston, MA
Print ISBN: 978-1-4612-9293-7
Online ISBN: 978-1-4613-2201-6
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