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| Titel |
A new two-phase erosion-deposition model for mass flows |
| VerfasserIn |
Shiva P. Pudasaini, Jan-Thomas Fischer |
| Konferenz |
EGU General Assembly 2016
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 18 (2016) |
| Datensatznummer |
250124917
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| Publikation (Nr.) |
 EGU/EGU2016-4424.pdf |
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| Zusammenfassung |
| Erosion, entrainment and deposition are complex and dominant, but yet poorly understood,
mechanical processes in geophysical mass flows. Here, we propose a novel, two-phase,
erosion-deposition model capable of adequately describing these complex phenomena
commonly observed in landslides, avalanches, debris flows and bedload transports.
The model enhances an existing general two-phase mass flow model (Pudasaini,
2012) by introducing a two-phase variably saturated erodible basal morphology. The
adaptive basal morphology allows for the evolution of erosion-deposition-depths,
incorporating the inherent physical process and rheological changes of the flowing
mixture. With rigorous derivation, we show that appropriate incorporation of the
mass and momentum productions and losses in conservative model formulation is
essential for the physically correct and mathematically consistent description of
erosion-entrainment-deposition processes. Simulation indicates a sharp erosion-front and
steady-state-rear erosion depth. The model appropriately captures the emergence and
propagation of complex frontal surge dynamics associated with the frontal ambient-drag
which is a new hypothesis associated with erosion. The novel enhanced real two-phase
model also allows for simulating fluid-run-off during the deposition process. The
model resembles laboratory experiments for particle-fluid mixture flows and reveals
some major aspects of the mechanics associated with erosion, entrainment and
deposition.
Reference:
Shiva P. Pudasaini (2012): A general two-phase debris flow model. J. Geophys. Res., 117,
F03010, doi: 10.1029/2011JF002186. |
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