Komarova, Natalia L. and Hulscher, Suzanne J. M. H.. (2000) Linear instability mechanisms for sand wave formation. Journal of Fluid Mechanics, Vol.41 . pp. 219-246. ISSN 0022-1120

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Abstract

A height- and flow-dependent model for turbulent viscosity is employed to explain the generation of sand waves in tidal seas. This new model resolves the problem of excitation of very long waves in sand wave formation, because it leads to damping of the long waves and gives a finite separation between the most excited mode and the zero mode. For parameters within their physically realistic ranges, a linear analysis of the resulting system yields a first excited mode whose wavelength is similar to the characteristic wavelength of sand waves observed in nature. The physical mechanism of sand wave formation as predicted by the new model is explained in detail. The dispersion relation obtained can be the starting point for a weakly nonlinear analysis of the system.

Item Type:	Journal Article
Subjects:	Q Science > QA Mathematics
Divisions:	Faculty of Science > Mathematics
Library of Congress Subject Headings (LCSH):	Sand waves -- Mathematical models, Sediment transport -- Mathematical models, Fluid mechanics, Tides, Turbulence, Algebras, Linear
Journal or Publication Title:	Journal of Fluid Mechanics
Publisher:	Cambridge University Press
ISSN:	0022-1120
Date:	June 2000
Volume:	Vol.41
Page Range:	pp. 219-246
Identification Number:	10.1017/S0022112000008429
Status:	Peer Reviewed
Access rights to Published version:	Open Access
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URI:	http://wrap.warwick.ac.uk/id/eprint/841

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