The Numerical Simulation Research On The Bending Evolution Of River And Its Hydrodynamic Process

Under the natural conditions, the river is always constantly changing and developing; In addition, the rivers will also be changing when it is interfered by artificial buildings built on the river. For two reasons which causes change of river, we call it the river channel evolution.The river channel evolution is it the result of the interaction of the river water and the river bed. All the rivers contains water flow and river bed the two contradictory aspects, which both restrict and influence each other. Since the interaction between river water flow and river bed implements through the sediment exchange of them, the basic laws of the river channel evolution are based on the basic rules of the sediment movement.Meandering channels can be seen as a most fundamental unit of river, and bend flow movement and river bed deformation is one of the major problems of river dynamics research. The research of the river bend evolution characteristics is not only to explore water-sediment movement law, but also the main basis to forecast river bend swing. The evolution and development of the meandering channels which is related to the erosion and collapse of the river banks and involves the river bank erosion-resisting capacity problem, is an important part of the theory of river bend evolution. With the rapid development of electronic computer, mathematics model and system simulation are more and more used to study the theory.The main content of this article roughly as follows:1) Through the river bend evolution characteristics of research, this paper expounds the related theory, and on this basis the paper is carried out.2) With the natural model experiment method, the physical model was used to explore the characteristics of the river bend and swing in different conditions.3) Establish a two-dimensional mathematical model of water and sediment and the bank stability model, using the finite element method, and combine with fortran programming language in the numerical simulation of the river bend. 4) Using the measured data of the physical model to test the mathematical model, the results indicate that both of the result is the same, which shows the correctness and rationality of the mathematical model.