Author(s): Pawel M. Rowinski; Wlodzimierz Czernuszenko
Linked Author(s): Pawel M. Rowinski
Keywords: Sediment particles trajectories; Sediment-laden flows; Sediment transport; Lagrangian model
Abstract: A micro-scale model for the sediment transport in a turbulent open channel flow is proposed. This model is based on a Lagrangian methodology consisting in the solution of the two-dimensional Newtonian equations of motion of interacting solid particles responding to stresses exerted by an ambient flow. The turbulent diffusion driven force, as an additional term in comparison with other studies, is included in model equations. It depends on particles’sizes, density relative to the carrier fluid, the variability of the particle concentration in vertical direction and the existing turbulence structure of the flow. The model reflects the balance of the drag force, the pseudo Saffman lift force, gravity, the buoyancy and the mentioned diffusive force. The model allows obtaining the trajectories and velocities of a particle moving in any mode-suspension, saltation or rolling. A supplementary stochastic model for the collision of a moving particle colliding with a bed is proposed as well. Possible trajectories of a particle in a turbulent open-channel flow are discussed.