Abstract
The paper describes an extension of the computational code LIQSEDFLOW proposed by the authors. The salient features of the code lie in its capability to describe the multi-phased physics of subaqueous sediment gravity flows. Specifically, it combines Navier-Stokes/continuity equations and equations for the advection and hindered settling of grains for a liquefied soil domain, with a consolidation equation for the underlying, progressively solidifying soil domain via a transition layer characterized by zero effective stress and a small yet discernible stiffness. Evolutions of the flow and solidification surfaces are traced as part of the solution using a volume-of-fluid (VOF) technique. The predicted features of the gravity flows of initially fluidized sediments with different concentrations conform to the observed performances in two-dimensional flume tests. The present results demonstrate the crucial role of two-phase physics, particularly solidification, in reproducing the concurrent processes of flow stratification, deceleration, and redeposition in subaqueous sediment gravity flows.
