Numerical Simulation For Coupling Of One-dimensional Rivernetwork And Two-dimensional Dike-break Waves

Once the reservoir is breached,the dike-break long waves cause great damage to the people's life and property who lives in the downriver area.especially in the Yangzi River downriver where it has the thickest river network.The density of the network even comes to 614～617km/km~2,and there are lots of low-lying fields in the networkarea.The protected bank is used to protect the area.The pumping station will drain the water from the low-lying field to the outside river,the water surface in the outside river is higher than it is in the low-lying field.So it becomes a hotspot to forecast the results brought by the past-areas'dike-break waves.In the paper,the hydraulic model of coupling 1 -D river network and 2-D dike-break waves really realizes the transition from 1-D calculation water area to 2-D water area,and it shows the process of river dike-breaking,the velocity variation of the breach flow and the flow characteristic of diffraction,refiection and deformation during the propagation of dike-break waves.The simulation can realistically show the burst process of the dike.It is conclude that the model can predict the submerge process and area effectively,provide academic base for establishment of flood forecast system and it has scientific decision reference and practical significance for flood warning service,.and also provides scientific basis for the analysis and prevention of disaster caused by dike destruction.