*Article* **Numerical Study and Force Chain Network Analysis of Sand Production Process Using Coupled LBM-DEM**

**Tian Xia 1,2, Qihong Feng 1,2,\*, Sen Wang 1,2, Jiyuan Zhang 1,2, Wei Zhang 1,2 and Xianmin Zhang 1,2**


**Abstract:** Sand production has caused many serious problems in weakly consolidated reservoirs. Therefore, it is very urgent to find out the mechanism for this process. This paper employs a coupled lattice Boltzmann method and discrete element method (LBM-DEM) to study the sand production process of the porous media. Simulation of the sand production process is conducted and the force chain network evolvement is analyzed. Absolute and relative permeability changes before and after the sand production process are studied. The effect of injection flow rate, cementation strength, and confining pressure are investigated. During the simulation, strong force chain rupture and force chain reorganization can be identified. The mean shortest-path distance of the porous media reduces gradually after an initial sharp decrease while the mean degree and clustering coefficient increase in the same way. Furthermore, the degree of preferential wettability for water increases after the sand production process. Moreover, a critical flow rate below which porous media can reach a steady state exists. Results also show that porous media under higher confining pressure will be more stable due to the higher friction resistance between particles to prevent sand production.

**Citation:** Xia, T.; Feng, Q.; Wang, S.; Zhang, J.; Zhang, W.; Zhang, X. Numerical Study and Force Chain Network Analysis of Sand Production Process Using Coupled LBM-DEM. *Energies* **2022**, *15*, 1788. https://doi.org/10.3390/en15051788

Academic Editor: Michele La Rocca

Received: 29 January 2022 Accepted: 23 February 2022 Published: 28 February 2022

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**Keywords:** lattice Boltzmann method; discrete element method; sand production; force chain network analysis
