Modeling submerged granular flow across multiple regimes using the Eulerian-Eulerian approach with shear-induced volumetric behavior

Abstract

The behavior of submerged granular flow is strongly dependent on the solid volume fraction and the viscosity discontinuity over a wide range of flow regimes. To obtain a general description of this type of flow, this study proposes a new model to compute solid effective stresses of submerged granular materials across multiple flow regimes. Here, based on the critical state soil mechanics framework, a new equation is proposed to describe the evolution of elastic reference of materials caused by elastoplastic deformation. The evolution of elastic reference subsequently informs the development of static pressure, and together with the dynamic pressure computed using a well-established blended model, resulting in a new approach to compute the solid pressure induced by both dynamic and static effects. The proposed model is then implemented in the Eulerian–Eulerian approach using the finite volume method to simulate the collapses of submerged granular columns, covering different flow regimes from quasi-static to viscous depositions. Simulation results agreeing well with experimental and numerical data in the literature are a testament to the performance of a well-developed constitutive law. In addition, the simulation results comprehensibly demonstrate the important role of interstitial fluid flow as well as the initial solid volume fraction in the collapsing process across different flow regimes with different packing densities. Furthermore, the effects of initial volume fraction, fluid pressure, and phase interaction forces on the flow responses are also discussed.