Numerical modeling of suffusion as an interfacial erosion process

Abstract : Suffusion is an internal erosion process which occurs when finer soil particles are detached by seepage flow and start moving within the pore space of larger particles. Suffusion can be viewed as clay/water interface erosion. The aim of this study is to use a numerical model for simulating surface erosion occurring at a fluid/soil interface subject to a flow process at pore scale. Balance equations with jump relations are used. A penalization procedure including a fictitious domain method is used to compute the Stokes flow around obstacles, in order to avoid body-fitted unstructured meshes and instead use fast and efficient finite volume approximations on Cartesian meshes. The evolution of the water/soil interface is described by using a level-set function. The ability of the model to predict suffusion is confirmed by several numerical simulations.