Study On Dam-break Flow Numerical Simulation And Dam-break Risk Analysis

The dissertation from the theorys hydraulic, together with geotechnical, hydrology and risk analysis, adopting technique means such as numerical calculation, mathematical statistic, resolve mechanics of embankment erosion and essential of dam-break risk, and constructing a new technique system of dam-break risk analysis which be based on numerical model of dam-break flow, which mainly comprise as following:(1) Study on mechanics of embankment erosion is basic of dam-break risk analysis. The essential of earthen dam-break process is an interactional process of flow and soil, in which involved many disciplines such as hydraulic, hydrology, geotechnical. The dissertation adopt multi-subject crossed method to research mechanics of breach enlarging, calculating breach flow discharge, soil erosion and transport process, breach enlarge process which base on basic steady flow equations, Meyer-Peter-Muller formula and slope stability theory. New model of breach flow numerical simulation be constituted, calculated program is compiled, applying by Yahekou dam breach and Bishui embankment breach flow hydrograph in Huma River. The result show that numerical model have advantages such as simple input data, clear concept and calculated result approximation survey data.(2) In the dissertation, discussing about which form of parabolic cross section effecting on dam-break flow propagating route in channel. Governing equations of nonprismatic channel unsteady are simply analyzed with the expressed form of channel parabolic cross section, and applied with dam sudden release problem in non-uniform wetted perimeter cross section, the function formula of dam-break wave parameters with cross section coefficient are quantitative analyzed.(3) According to the principle of Discontinuous Finite-Element Methods, computational scheme be developed for the shallow water equations. The bottom slope source terms is treated with Water Level Formulation(WLF) to obtain well-balanced and stability scheme. Adopted with limit function and three steps Runge-Kutta method are to obtain high-order accuracy result on time and space in the scheme. The simulation of model tests shows the...