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Titel |
Closure relations for bidispersed shallow granular flows - towards understanding segregation in geophysical flows |
VerfasserIn |
Thomas Weinhart, Ate te Voortwis, Stefan Luding, Anthony Thornton |
Konferenz |
EGU General Assembly 2013
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Medientyp |
Artikel
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Sprache |
Englisch
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Digitales Dokument |
PDF |
Erschienen |
In: GRA - Volume 15 (2013) |
Datensatznummer |
250073869
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Zusammenfassung |
The flow behaviour of shallow granular chute flows for uniform particles is well-described by
the hstop-rheology [Y. Forterre, O. Pouliquen, J. Fluid Mech. 486, 21–50 (2003)].
Geophysical flows, however, are often composed of highly non-uniform particles that differ
in particle (size, shape, composition) or contact properties (friction, dissipation, cohesion).
The flow behaviour of such mixtures can be strongly influenced by segregation
effects.
Here, we study the influence of particle size segregation on the flow behaviour of
bidispersed flows using the discrete particle method. We consider mixtures where both large
and small particles have the same contact properties (such as friction and restitution). We
derive closure relations for the granular shallow layer equations, and study their
dependence on the segregation profile and the dispersity. We further account for the
dynamics of the flows by measuring their segregation Peclet numbers. The resulting
model will allow us to make better predictions for large-scale geophysical flows. |
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