Abstract
In order to investigate fluid flow in fractured porous media, this study presents a multi-field fracture-pore seepage model based on the discrete element method. The fluid transport, heat conduction and convection in pore system and fractures are considered in the model. The numerical model is validated using seepage tests to ensure correctness and accuracy. Besides, the established model is analyzed for two scenarios: isotropic micro-fractures and anisotropic micro-fractures with different numbers of micro-fractures. The relationship between the macro permeability and micro permeability is investigated, which is further used to determine different micro-fracture distributions based on the model and field conditions. Furthermore, the proposed model is applied to a field CO2 sequestration experiment to simulate the CO2 injection process, as well as the temperature, and pressure variations. The results indicate that the proposed model can provide insight into fracture distribution by combining macro-micro permeability relationship and field conditions. The results also help predict the fluid flow, facilitating the simulation of field engineering applications and investigation of fluid migration characteristics.