Accurate simulation of the sediment processes at the vicinity of the sediment bed/water interface is still very difficult because of the multi-physic character of the problem. A soil is a continuum and porous media having solid properties such as elasticity and plasticity. It is usually considered as impermeable boundary which could evolve through erosion and deposition fluxes. Flow characteristics close to the liquid-bed interface are poorly described by soil mechanics and rheological characteristics of the soil are usually neglected by fluid mechanics. In order to account for the flow domain as a whole, extending from the substratum up to the water surface as a continuum body, in which all physical phenomenon such as suspension, hindered settling, consolidation, erosion and re-suspension, could be taken in consideration, a unified approach of continuum mechanic should be applied. This is why we propose herein a more general model, which does not split regions. This unified approach enables the description of the ‘liquid like’ or/and ‘solid like’ behaviour. This paper presents new development of the two phase Eulerian-Eulerian NSMP (Navier-Stokes Multi-Phase) code. The new development consists in computing a solid and elastic stress following the procedure by Greenshield and Weller (2005) and a specific treatment for the liquid-like to solid-like transition. The new model is validated against laboratory experiment reproducing the test of Water injection dredging by Badr et al. (2013). Here we consider the experimental configuration by Badr et al. (2013) which consists in a granular (non-cohesive) bed subjected to a vertical impinging jet in a 2D geometry (Hele Shaw cell, 50cm height, 20cm wide with 3.2cm gap). A comparison between the results obtained by the present model with the previous studies (Hanson and Cook, 2004; Rajaratnam and Mazurek, 2005) is done.
Nguyen, Dan; Uh Zapata, Miguel; Gauthier, Georges; Gondret, Philippe; and Pham Van Bang, Damien, "A Two Phase Numerical Model For The Water Injection Dredging (WID) Technology: An Unified Formulation For Continuum Mechanic" (2014). CUNY Academic Works.