Sheetflow simulator for numerical prediction of sediment transport rate

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In sheetflow regime, great amount of sediment is transported in short period of time, hence the effect of sheet flow sediment transport plays a significant role in the prediction of sea-bed profile change. Most of sensors for the flow measurement does not work in the sheetflow condition, due to the presence of a high concentration sediment. Furthermore, the video-film analysis, which is the effective tool to investigate the sheet flow sediment transport, requires the time-consuming processes.In this study, two approaches for the development of the analysis of sediment sheetflow are conducted. The one is the numerical modeling of the sediment sheet flow by the granular material model, or the DEN (distinct element method) ; the other is the simplified process of the video film analysis by the use of the free wares. In addition to these approaches, some significant factors in the natural coast should be investigated as the external driving forces of the sediment transport process. Hence the primal subjects of this study should be as follows : (l) the hydraulic experiment of sediment sheetflow by the oscillatory water tunnel ; (2) the development of numeral movable bed for the simulation of sediment sheetflow ; (3) the external driving forces of sediment sheetflow in a natural coast (3-l multi-directional irregular waves ; 3-2 obliquely wave run-up ; 3-3 seepage flow due to wave run-up ; and 3-4 liquefaction of sea bed due to propagating waves).