Numerical prediction of turbidity currents on unsteady sediment-supply

Abstract

A three-dimensional (3D) numerical model of unstable turbidity currents is developed based on the mechanism of sediment transport and turbulence theory. In this model, numerical simulation of turbidity currents without subsequent supply of muddy water was conducted using the same parameters as were used in the flume experiments. The evolution process of turbidity currents of completely losing supplies observed in the experiment was simulated by the model; validation of the numerical model and the algorithm was conducted. If momentarily interrupted process is regarded as a special case of the gradually interrupted, based on the preceding numerical simulation validity, it is feasible to simulate the motion law of turbidity currents under losing gradually supplies. By this method in this article, the characteristic of sediment-laden flow of losing gradually supplies was obtained, as well as its relationship between front velocity and sediment concentration.