Numerical Simulations of Density-driven Convection in a Fractured Porous Media
Creators
- 1. Korea Institute of Geoscience and Mineral Resources
- 2. Korea institute of geoscience and mineral resources
Description
Dissolution trapping is one of the primary mechanisms of carbon dioxide (CO2) storage in a geological formation. In this study, a numerical model was used to examine the impacts of single and multiple fractures on the transport of dissolved CO2 plumes in various geological settings. The effects of the fracture angle (horizontal angle, low-angle, high-angle) and fracture-matrix permeability ratio (1-3 order) on density-driven CO2 convection were systematically investigated. The fractures were found to play time-varying roles in the homogeneous media by serving as preferential pathways for both CO2-rich plumes (fingers) and CO2-free water. The competition between the enhancement of convective mixing and the inhibition of finger growth by the upward flow of fresh water generated a complex flow system. The interaction between the strong upward flow of fresh water through the fractures and the falling CO2-rich fingers through the porous matrix induced a positive feedback, resulting in accelerated domain-scale circulation and CO2 dissolution.