Advanced topics in sediment transport modelling: non-alluvial beds and hyperconcentrated flows

In this chapter, we first present an original two-phase flow model for the water-sediment mixture, acting as a unified basis for all our subsequent developments. Next, we focus on two topics in which we have made original contributions, namely sediment routing on alluvial and non-alluvial beds and modelling of transient hyperconcentrated flows. In both cases, we use our original two-phase flow modelling framework to derive specific governing equations, for which we discuss their mathematical properties, detail appropriate finite volume numerical scheme and demonstrate their validity through a number of test cases.