Multiphysics Lattice Discrete Particle Modeling (M-LDPM) for the Simulation of Shale Fracture Permeability

Li, Weixin; Zhou, Xinwei; Carey, J. William; Frash, Luke P.; Cusatis, Gianluca

doi:10.1007/s00603-018-1625-8

Title: Multiphysics Lattice Discrete Particle Modeling (M-LDPM) for the Simulation of Shale Fracture Permeability

Journal Article · Thu Oct 25 00:00:00 EDT 2018 · Rock Mechanics and Rock Engineering

DOI:https://doi.org/10.1007/s00603-018-1625-8· OSTI ID:1525825

^[1]; Zhou, Xinwei ^[2];

^[3];

^[1]

Northwestern Univ., Evanston, IL (United States)
ES3, San Diego, CA (United States)
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

A three-dimensional multiphysics lattice discrete particle model (M-LDPM) framework is formulated to investigate the fracture permeability behavior of shale. The framework features a dual lattice system mimicking the mesostructure of the material and simulates coupled mechanical and flow behavior. The mechanical lattice model simulates the granular internal structure of shale, and describes heterogeneous deformation by means of discrete compatibility and equilibrium equations. The network of flow lattice elements constitutes a dual graph of the mechanical lattice system. A discrete formulation of mass balance for the flow elements is presented to model fluid flow along cracks and intact materials. The overall computational framework is implemented with a mixed explicit–implicit integration scheme and a staggered coupling method that makes use of the dual lattice topology enabling the seamless two-way coupling of the mechanical and flow behaviors. The proposed model is used for the computational analysis of shale fracture permeability behavior by simulating triaxial direct shear tests on Marcellus shale specimens under various confining pressures. The simulated mechanical response is calibrated against the experimental data, and the predicted permeability values are also compared with the experimental measurements. Moreover, the paper presents the scaling analysis of both the mechanical response and permeability measurements based on simulations performed on geometrically similar specimens with increasing size. The simulated stress strain curves reflect a significant size effect in the post-peak due to the presence of localized fractures. The scaling analysis of permeability measurements enables prediction of permeability for large specimens by extrapolating the numerical results of small ones.

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Research Organization:: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)

Sponsoring Organization:: USDOE Office of Science (SC), Basic Energy Sciences (BES)

Grant/Contract Number:: 89233218CNA000001; AC52-06NA25396

OSTI ID:: 1525825

Report Number(s):: LA-UR-18-22183

Journal Information:: Rock Mechanics and Rock Engineering, Vol. 51, Issue 12; ISSN 0723-2632

Publisher:: SpringerCopyright Statement

Country of Publication:: United States

Language:: English

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Cited by: 26 works

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