3D numerical simulation of backward erosion piping tube experiments

Backward erosion piping (BEP) is an internal erosion mechanism, driven by the detachment of particles at the pipe tip and erosion of the particles along the pipe walls and bottom. This erosion mechanism was extensively studied in (Robbins et al., 2018), who describe horizontal tube experiments in which the head loss along the erosion pipe was measured during pipe formation. This study investigates the ability of numerical models to predict the head loss in the erosion pipe in a 3D situation by simulating the tube experiments using DgFlow (Van Esch et al., 2013), a finite element (FE) program in which the groundwater flow is coupled to the pipe flow using line elements, and using the 3D finite element program described in Robbins and Griffiths (2018), in which backward erosion is simulated by changing soil elements to pipe elements.