Research On The 1-D And 2-D Mathematical Model And Analysis Of Flood Risk In The XiSan Basin

China is one of the countries which have a lot of rivers in the world.Many large and medium-sized cities are built on a riverside.When floods occur frequently,it will bring large losses to the local region.In recent years,we usually establish a wide flood storage and detention area on both riverside to slow the flood and avoid the harm of it.The area of the flood storage and detention area generally larger,area with villages and towns,roads,railways and other facilities.In order to protect people,property facilities from flood,we need to make and improve flood control scheduling plan in the flood detention zone.Computer programming method is used to simulate flood routing process in this paper,and the author assess the flood risk of detention basin,in order to establish flood control plan scheduling and reduce the flood losses.This paper has established a one-dimensional model grid of channel basing on generalized river.And the two-dimensional ground unstructured rectangle meshes is automatically generated according to topographic variation.The governing equation is discreted using the finite volume method.1-D and 2-D nesting and cohesion flood routing numerical model in the three western basin is established.Flood model is debugged using the 63.8 historical data,By testing the model,the model precision is good and can be used for forecast.Numerical models with different return period of design flood frequency flood routing simulation has been done.By sorting and statistical 24 kinds of working condition of the corresponding simulated data,we can get results like enabled time,inundation area,submerged depth and the hydrologic data of every flood detention zone.By analyzing the flood routing results of various conditions,we have drawn the flow chart of the flooding evolution,plains,flow diagram and the water depth contour map to analyze the effect of different return period of the flooding the plains.Through the flood risk map,relevant departments can make a decision on flood control and disaster mitigation.This paper studies the MIKE series software's application in a two-dimensional cohesion,and establish a model to simulate flood routing.Compared with the previous model,the model's simulation results in this paper are basically identical.