Numerical investigation of particle migration and pore clogging during methane hydrate extraction in porous media

Abstract

Sand production is an important research direction in hydrate extraction, which involves particle migration and pore clogging mechanism in gas-liquid two-phase flow. This study employs a coupled resolved CFD-DEM-VOF (computational fluid dynamics, discrete element method, and volume of fluid) approach to simulate particle dynamics in a microfluidic chip with a column matrix. The work elucidates the mechanisms of particle migration and pore clogging in gas-liquid two-phase flow through porous media, while systematically evaluating the effects of key multiphase parameters. The results indicate that when gas is injected, the water flow creates a fluid channel between the bubbles, accelerating the fluid velocity within the channel. As a result, particles migrate along the fluid channel, leading to increased aggregation and a higher probability of pore clogging. In contrast, the fluid velocity outside the channel is slower. Many particles in the low velocity regions are unable to migrate, further contributing to the risk of pore clogging. Parameter analysis reveals that both high and low gas injection fractions reduce the likelihood of pore clogging. Additionally, both excessively high and low contact angles negatively impact particle migration. Furthermore, the probability of pore clogging increases with rising surface tension and particle injection rate.