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| Titel |
A multilayer approach for turbidity currents |
| VerfasserIn |
Enrique Fernandez-Nieto, Manuel J. Castro Diaz, Tomás Morales de Luna |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250146250
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| Publikation (Nr.) |
 EGU/EGU2017-10265.pdf |
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| Zusammenfassung |
| When a river that carries sediment in suspension enters into a lake or the ocean it can form a
plume that can be classified as hyperpycnal or hypopycnal. Hypopycnal plumes occurs if the
combined density of the sediment and interstitial fluid is lower than that of the ambient.
Hyperpycnal plumes are a class of sediment-laden gravity current commonly referred to as
turbidity currents [7,9].
Some layer-averaged models have been previously developed (see [3, 4, 8] among others).
Although this layer-averaged approach gives a fast and valuable information, it
has the disadvantage that the vertical distribution of the sediment in suspension is
lost.
A recent technique based on a multilayer approach [1, 2, 6] has shown to be specially
useful to generalize shallow water type models in order to keep track of the vertical
components of the averaged variables in the classical shallow water equations. In [5]
multilayer model is obtained using a vertical discontinuous Galerkin approach for which the
vertical velocity is supposed to be piecewise linear and the horizontal velocity is supposed to
be piecewise constant.
In this work the technique introduced in [5] is generalized to derive a model for turbidity
currents. This model allows to simulate hyperpycnal as well as hypopycnal plumes. Several
numerical tests will be presented.
References
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[6] E. D. Fernández-Nieto, E. H. Koné, T. Morales de Luna, and R. Bürger.
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[7] T. Mulder and J. P. M. Syvitski. Turbidity Currents Generated at River
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[8] G. Parker, Y. Fukushima, and H. M. Pantin. Self-accelerating turbidity
currents. Journal of Fluid Mechanics, 171:145–181, (1986).
[9] J. D. Parsons, J. W. M. Bush, and J. P. M. Syvitski. Hyperpycnal
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