A TWO-LAYER NON-HYDROSTATIC LANDSLIDE MODEL FOR TSUNAMI GENERATION ON IRREGULAR BATHYMETRY
AbstractIn this study, a two-layer landslide model is presented for investigating submarine landslides and generated waves that propagate over irregular bathymetry. The landslide is described as either a mudflow or a fully saturated granular flow, which are distinguished by using different rheological closure based on physical principles. Depth-averaged governing equations for the landslide are derived in a regular Cartesian coordinate system, and take into account the effect of vertical acceleration and interface traction from the upper-layer water. In addition, sediment erosion from basal boundary and water entrainment are also considered. Tsunami waves generated by the landslide are simulated by the three-dimensional non-hydrostatic wave model NHWAVE (Ma et al., 2012). The governing equations for both the lower-layer slide and the upper-layer water body are solved using a Godunov-type finite volume TVD scheme in space and a Strong Stability-Preserving (SSP) Runge- Kutta scheme in time.
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