Jeevan Kafle
Advanced dynamic simulation of submarine mass movements
Subaerial and submarine mass flows are very dangerous rapid gravity-driven flows consisting of solid grains mixed with viscous fluid and are very important sediment transport mechanisms. Examples include the huge landslides and debris flows in the coastal and mountain regions, and particle transport in the mountain lakes, rivers and reservoirs. As there are hundreds of mountain rivers, lakes, and several reservoirs for the hydro-electric power generation in the Himalayas, these may severely be hit by the sudden breaking-off of the hanging glaciers, landslides, debris flows and rock-slides, thereby triggering tremendous water waves - called the Mountain Tsunamis, debris and mud flows. Coincident with the submarine mass movements, these events may severely damage environments, water supply and aquatic systems, irrigation canals, and hydro-electric power generating plants. Although landslide and debris flows induced tsunamis and submarine mass movements, and particle-laden flows are extremely destructive natural hazards, these events are still very poorly understood in terms of dimensions, mechanics and phase interactions.
Here, we focuse on the simultaneous dynamic simulation of three-dimensional and real two-phase subaerial and submarine landslide and debris flow, the resulting tsunami generation and propagation upon debris impact at the reservoir, lakes, rivers and ocean; the subsequent submarine landslide, debris flow, turbidity current and particle transport in the fluid, and the entire analysis of all three types of waves and their complex interactions. Submarine debris flow-obstacle-interactions and the dynamic impacts of submarine debris and surface tsunami in the coastal lines, and the reservoir dams will be investigated in detail. This will be achieved by employing the general two-phase physical-mathematical mass flow model [8] and other relevant models, e.g., [1, 5, 6, 7, 12]. The model equations will be solved numerically by applying the high-resolution shock-capturing numerical scheme [6, 7, 11]. These innovative and unified approaches [9, 10] allow for the adequate modeling of debris induced tsunami and submarine sediment transport.
References:
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4. J. Kafle. Dynamic Interaction Between a Two-Phase Submarine Landslide and a Fluid Reservoir. M. Phil. Dissertation, Kathmandu University, School of Science, Dhulikhel, Kavre, Nepal, 2014.
5. E. B. Pitman and L. Le. A two-fluid model for avalanche and debris flows. Philos. Trans. R. Soc. A, 363(3):1573-1602, 2005.
6. S. P. Pudasaini, Y. Wang, and K. Hutter. Modelling debris flows down general channels. Nat. Hazards Earth Syst. Sci., 5:799-819, 2005.
7. S. P. Pudasaini and K. Hutter. Avalanche Dynamics: Dynamics of Rapid Flows of Dense Granular Avalanches. Springer, New York, 2007.
8. S. P. Pudasaini. A general two-phase debris flow model. Journal of Geophysical Research, 117:F03010, 2012. doi:10.1029/2011JF002186.
9. S. P. Pudasaini and S. A. Miller. A real two-phase submarine debris flow and tsunami. American Institute of Physics Proceedings, 1479:197-200, 2012.
10. S. P. Pudasaini. Dynamics of submarine debris flow and tsunami. Acta Mechanica, 225(8), 2423-2434, 2014.
11. Y. C. Tai, S. Noelle, J. M. N. T. Gray, and K. Hutter. Shock-capturing and fronttracking methods for granular avalanches. J. Comput. Phys., 175:269-301, 2002.
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