A description of water and sediment flow in the presence of obstacles with a two-dimensional, lattice BGK-cellular automata model

Abstract

The spatial distribution of water and sediment flow in the presence of obstacles on the soil surface is described with a coupled two-dimensional, lattice BGK (the Bhatnagar, Groos, and Krook version of the lattice Boltzmann equation) cellular automata model. The model reproduces the main water flow characteristics of the Bunte and Poesen [1993] experiment well, as well as the mean runoff velocity. The model also approximates the main features of local scouring and sediment yield of the experiment. Although the results obtained in two dimensions are encouraging, the consideration of the erosive action of the vortexes on a plane perpendicular to the bed would improve the characterization of the scouring patterns in the stagnation points developed upstream from the obstacles.