tailieunhanh - Báo cáo "Numerical simulations of overland floods in urban areas using a conservative Godunov-type scheme "

Floods in urban areas due to levee overtopping and/or breaking may cause a lot of severe damage of property and lost of human lives. In case of river dike and/or dam break, the problem is characterized by the overland propagation of discontinuity fronts or hydraulic jumps. !t is of immense importance that urban planners and personnel have tools to assist in predicting and evaluating beforehand the flood process in such incidents. Recently, with the rapid development of computer resources and numerical methods, numerical models based on mathematical models for simulation of flood scenarios become highly useful. A model for the. | VNU Journal of Science Earth Sciences 25 2010 168-176 Numerical simulations of overland floods in urban areas using a conservative Godunov-type scheme Nguyen Tat Thang Institute of Mechanics Vietnam Academy of Science and Technology VAST Received 14 September 2009 received in revised form 24 September 2009 Abstract. Floods in urban areas due to levee overtopping and or breaking may cause a lot of severe damage of property and lost of human lives. In case of river dike and or dam break the problem is characterized by the overland propagation of discontinuity fronts or hydraulic jumps. It is of immense importance that urban planners and personnel have tools to assist in predicting and evaluating beforehand the flood process in such incidents. Recently with the rapid development of computer resources and numerical methods numerical models based on mathematical models for simulation of flood scenarios become highly useful. A model for the simulation of two dimensional 2D overland floods in urban areas has therefore been developed. A finite volume Godunov-type numerical scheme is applied in the model. This numerical scheme has some important advantages. It is a conservative scheme and able to model more accurately hydraulic shockwave propagation. The scheme is based on unstructured computational meshes in general to deal with complicated urban geometries. The model has been applied to studying two experiments of overland floods. These experiments were carried out in research institutions in Japan and Italy. The computed results show general agreement with the measured ones. The model is prospective for analyzing overland flood process in practical cases. Keywords Numerical simulation overland flood godunov-type scheme Un-Structured meshes. 1 Introduction Mathematical models for the numerical solution of the 2-D Saint Venant equations have long been developed. Applications of such models which are based on advanced numerical techniques to the simulations of overland .