Numerical Simulation Of Stormwater And Street Flood In City

In the process of the urbanization,with the centralization of population and wealth,the loss of urban flood disaster is increasing,which occupies a very large proportion in the flood disaster losses,in the case of Flood Control and Drainage standard is low,the frequency of occurrence of floods is increasing year by year.Flood source of piedmont cities is divided into flood disasters and rainfall.Under the high-intensity rainfall,whether flood or rainfall,all will result in a very large city disaster losses.Thus by developing the Stormwater Simulation Model to simulate the flooding area and depth under rainstorm in cities,which can provide technical support for relative department.An extensive literature review is done for urban stormwater simulation techniques.On this basis,the paper describes the main contents.Firstly,introduce the theory and methods of numerical simulation.Using the one-dimensiona model based on Saint-Venant equations to simulate river,and using Finite Difference Method to solve Saint-Venant equations.Using the two-dimensional based on Navier-Stokes equations to simulate the city,and using Roe based on unstructured grids to solve.Real terrain method was established by coupling unstructured mesh and special border,reduction terrain of aqueduct in the area by using the Natural Neighbor Interpolation.Secondly,introduce the theory and methods of the ground runoff formation and flow concertration and the computation of pipeline drainage.Using comprehensive surface runoff coefficient law to solve ground runoff,flow concertration is solved by using the nonlinear reservoir.The computation of pipeline drainage is solved by using nonlinear-kinematic wave equation.Coupled the surface runoff model and the underground drainage network model to simulate the bi-directional flow interactions between sewers and overland surface flow.Thirdly,this model is applied to Yinchuan to simulate flood and rainfall.In the calculation scheme of flood,evolution of flood is simulated and the flooded area and the water quantity is statistics.In the calculation scheme of rainfall,ground water is simulated and water depth and water area is statistics.At last,evolution of flood in the street is simulated and evolution features of flood is analyzed in detail.Finally,a summary is given and some problems to be further studied are discussed.