Numerical modelling to define deposition rate and dispersion coefficient of cohesive sediments

A detailed description of the behavior of cohesive fine-grained sediments is a very complicated task. Simulation of cohesive sediment movement has been successfully treated in the past using the macroscopic properties of the water-sediment system. In this study, a 1-Dimensional equation of cohesive sediment has been proposed for deposition term and dispersion coefficient of mass transfer equation. This equation has been solved by Control Volume method and calibrated with laboratory data. The tests have been done in a flume with 0.3m diameter, the slope 0.00008, discharge between 3~5.7 liter per second and the concentration of 4~8 gram per liter. The model shows that the dispersion coefficient is a function of Reynolds number and rate of velocity to shear velocity.