Microscopic mechanical analysis of sand production using a new arbitrary resolved-unresolved CFD-DEM model

Numerical simulation of fluid‐particle interaction in geomechanics using an extended CFD‐DEM approach with a super‐quadric model of non‐spherical particles

“…In our study, the calculation of the drag force f d,i acting on the particle i is defined as 24,33 : $$$$\begin{equation}{{\bf{f}}}_{d,i} = \frac{1}{8}\ {C}_D{\rho }_f\pi d_V^2\left| {{{\bf{U}}}_f - {{\bf{U}}}_p} \right|\ \left( {{{\bf{U}}}_f - {{\bf{U}}}_p} \right) = \frac{{{\beta }_i{V}_{p,i}}}{{{\alpha }_f\left( {1 - {\alpha }_f} \right)}}\ \left( {{{\bf{U}}}_f - {{\bf{U}}}_p} \right)\end{equation}$$$$where V p,i is the volume of the particle i , d V is the particle diameter of a volume equivalent sphere. C D = C D0 f ( a f , Re , etc.)…”

“…To simulate fluid‐particle interactions, a coupling numerical scheme (CFD‐DEM) for a two‐way coupling between the computational fluid dynamics (CFD) and discrete element method (DEM) was proposed by Tsuji 22 . It becomes an increasingly popular Eulerian‐Lagrangian method for modeling geotechnical problems involving particle‐fluid interactions 23–26 …”

“…The CFD‐DEM coupling approach has been increasingly applied in a wide range of applications 24,33–35 . There are various empirical models used in the unresolved CFD‐DEM model for evaluating particle‐fluid interactions.…”

“…22 It becomes an increasingly popular Eulerian-Lagrangian method for modeling geotechnical problems involving particle-fluid interactions. [23][24][25][26] Massive studies on fluid-particle interactions are all based on spherical particles, as non-spherical CFD-DEM simulations remain a challenging problem up to date. The main challenges lie in correctly constructing…”

Research advance of numerical simulation methods for sand production prediction of unconsolidated sandstone

“…With the rapid development of global economy, the demand for oil and gas resources keeps rising, unconsolidated sandstone reservoirs occupy a very important position in China's oil and gas resources (Wang et al, 2010) (Zhang, 2021) (Yan et al, 2021). In the process of drilling and producing oil in unconsolidated sandstone reservoir, the stress and pore pressure around the oil production cavity will be redistributed, which will cause serious problems such as sand production in the production stage (Wang et al, 2022). Sand production not only damages borehole integrity, but also leads to reduced oil and gas production, equipment corrosion and impact on production safety during production (Ahad et al, 2020) (Song et al, 2021).…”