The nonlinear dynamic analysis of sediment particles near river bed

According to the equation of discrete solid particles' motion in arbitrary flow field, the dynamic characteristics and trajectories of sediment particles are discussed. The small disturbance method is used to analyze the stability of sediment particles at the equilibrium point, it is shown that the change of turbulence frequency will lead to the sudden change of sediment particles, under the condition of a certain periodic excitation amplitude; and under the condition of certain periodic excitation amplitude, the change of sediment particle size will also lead to the sudden change of sediment particle movement, All of the above prove that the movement of sediment particles near the river bed surface has a catastrophe.