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| Titel |
Energy dissipation by submarine obstacles during landslide impact on reservoir - potentially avoiding catastrophic dam collapse |
| VerfasserIn |
Jeevan Kafle, Parameshwari Kattel, Martin Mergili, Jan-Thomas Fischer, Bhadra Man Tuladhar, Shiva P. Pudasaini |
| 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 |
250143135
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| Publikation (Nr.) |
 EGU/EGU2017-6834.pdf |
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| Zusammenfassung |
| Dense geophysical mass flows such as landslides, debris flows and debris avalanches may
generate super tsunami waves as they impact water bodies such as the sea, hydraulic
reservoirs or mountain lakes. Here, we apply a comprehensive and general two-phase,
physical-mathematical mass flow model (Pudasaini, 2012) that consists of non-linear and
hyperbolic-parabolic partial differential equations for mass and momentum balances, and
present novel, high-resolution simulation results for two-phase flows, as a mixture of solid
grains and viscous fluid, impacting fluid reservoirs with obstacles. The simulations
demonstrate that due to the presence of different obstacles in the water body, the intense
flow-obstacle-interaction dramatically reduces the flow momentum resulting in the rapid
energy dissipation around the obstacles. With the increase of obstacle height overtopping
decreases but, the deflection and capturing (holding) of solid mass increases. In addition, the
submarine solid mass is captured by the multiple obstacles and the moving mass
decreases both in amount and speed as each obstacle causes the flow to deflect
into two streams and also captures a portion of it. This results in distinct tsunami
and submarine flow dynamics with multiple surface water and submarine debris
waves. This novel approach can be implemented in open source GIS modelling
framework r.avaflow, and be applied in hazard mitigation, prevention and relevant
engineering or environmental tasks. This might be in particular for process chains,
such as debris impacts in lakes and subsequent overtopping. So, as the complex
flow-obstacle-interactions strongly and simultaneously dissipate huge energy at
impact such installations potentially avoid great threat against the integrity of the
dam.
References:
Pudasaini, S. P. (2012): A general two-phase debris flow model. J. Geophys. Res. 117,
F03010, doi: 10.1029/ 2011JF002186. |
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