An improved VOF-DEM model for soil-water interaction with particle size scaling. (December 2020)

• Record Type: Journal Article
• Authors: He, Xuzhen; Xu, Haoding; Li, Wengui; Sheng, Daichao
• Is Part Of: Computers and geotechnics. Volume 128(2020)
• Publication Date: 2020-12
• Subjects: VOF-DEM -- Soil-water interaction -- Particle size scaling; Engineering geology -- Data processing -- Periodicals; Soil mechanics -- Data processing -- Periodicals; Rock mechanics -- Data processing -- Periodicals; 624.1510285
• DOI: 10.1016/j.compgeo.2020.103818
• Languages: English
• ISSNs: 0266-352X

Abstract

Abstract: This study presents an improved VOF-DEM model where the Darcian velocity and a compound variable are treated as unknowns in the pressure-velocity calculation procedure such that the use of interpolated porosity at cell faces is minimised and stability is ensured even if the porosity field is not smooth or even ragged. A higher-order porosity estimation method is also used such that the porosity and interaction force are evaluated correctly when the CFD cell size is of the same order as the DEM particle size. Additionally, a particle size scaling technique is proposed to let the DEM particle size different from the real soil particle size and soil-water interaction forces are the same as when the real soil particle size is used. This is achieved by modifying the calculation of drag force. The solution scheme is verified in two case where analytical solutions exist. Particle size scaling technique is also used and tested in permeability tests and wave interaction with porous structure. Subsequently, the settling and collision of particles in water, dambreak of soil-water mixture and submerged landslides are simulated. With the present improvements and the particle size scaling, the capability of the VOF-DEM is extended in soil-water interaction problems.