Fiber Bragg grating‐based experimental and numerical investigations of CO₂ migration front in saturated sandstone under subcritical and supercritical conditions

Abstract

Carbon dioxide (CO2) can be at risk of leakage during its storage in deep saline aquifers due to stress field changes in the reservoir. The aim of this study was to investigate the effects of CO2 injection pressure on dynamic strain response of the reservoir and the CO2 migration process. A series of core flooding experiments was performed with the‐state‐of‐art fiber Bragg grating sensors. The results show that the surface strain response was linearly correlated with CO2 injection pressure. Carbon dioxide migration velocity can be estimated from the strain response time differences among three gratings. The migration velocity of supercritical CO2 is higher than that of liquid CO2 but lower than gaseous CO2. Finally, numerical simulation was applied to model the CO2 migration process and the simulated values were compatible with those of experiments. © 2018 Society of Chemical Industry and John Wiley & Sons, Ltd.

Deformation‐Based Monitoring of Water Migration in Rocks Using Distributed Fiber Optic Strain Sensing: A Laboratory Study

“…In a previous study, we used DFOSS to monitor the migration of a CO 2 plume in rocks, particularly for the underground storage of CO 2 (Zhang et al, 2019). Fan et al (2019) applied the quasi-distributed fiber Bragg grating sensing method (with three monitoring points) to detect the front of a CO 2 plume.…”

The effects of porosity and permeability changes on simulated supercritical CO2 migration front in tight glutenite under different effective confining pressures from 1.5 MPa to 21.5 MPa

“…Equations COMSOL TM can be used to simulate migration characteristics of two-phase flow in porous media by the finite element method and many researchers have done similar work in this area. [26][27][28] Typically, multiphase flow in porous media multiphysics interface is used to simulate immiscible displacement processes in which the two physical fields of phase transport in porous media and Darcy's law are coupled. 29 The basic mass conservation equations for two-phase immiscible flow without considering gravitational effects are listed as follows:…”

Dissolution and Deformation Characteristics of Limestones Containing Different Calcite and Dolomite Content Induced by CO2‐Water‐Rock Interaction

“…However, the strain response is a direct reflection of fluid injection stress and migration front within pore structure. For example, Fan et al (2019) performed a series of core flooding experiments monitored by fiber Bragg grating (FBG), and they found that surface strain response of rock was linearly correlated with CO 2 injection pressure and CO 2 migration could be monitored by FBG. Xu et al (2022) experimentally investigated the CO 2 leakage process along fault rock, and the result found that the small strain induced by leakage stress could be monitored by FBG.…”