Developing a 2D vertical flow and sediment transport model for open channels using the Youngs-VOF method

A 2D vertical(2DV) numerical model,without σ-coordinate transformation in the vertical direction,is developed for the simulation of flow and sediment transport in open channels.In the model,time-averaged Reynolds equations are closed by the k-ε nonlinear turbulence model.The modified YoungsVOF method is introduced to capture free surface dynamics,and the free surface slope is simulated using the ELVIRA method.Based on the power-law scheme,the k-ε model and the suspended-load transport model are solved numerically with an implicit scheme applied in the vertical plane and an explicit scheme applied in the horizontal plane.Bedload transport is modeled using the Euler-WENO scheme,and the grid-closing skill is adopted to deal with the moving channel bed boundary.Verification of the model using laboratory data shows that the model is able to adequately simulate flow and sediment transport in open channels,and is a good starting point for the study of sediment transport dynamics in strong nonlinear flow scenarios.