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Linear instability mechanisms for sand wave formation
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Komarova, Natalia L. and Hulscher, Suzanne J. M. H.. (2000) Linear instability mechanisms for sand wave formation. Journal of Fluid Mechanics, Vol.41 . pp. 219246. ISSN 00221120

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Official URL: http://dx.doi.org/10.1017/S0022112000008429
Abstract
A height and flowdependent 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:  00221120 
Date:  June 2000 
Volume:  Vol.41 
Page Range:  pp. 219246 
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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