Numerical analysis of fluid flow behavior in micro fracture of coal matrix

Coal beds are very complex porous media that exhibit heterogeneity, dual-porosity, and stress sensitivity. Simulation models for fluid flow from coal matrix for coal bed methane (CBM) and enhanced coal bed methane (ECBM) recovery have significantly progressed in recent decades. Analytical models have limitations or challenges in application due to assumptions and oversimplification. Therefore, in this study, numerical modeling and simulations were carried out to investigate the fluid flow behavior in the microchannel of the coal matrix. A variation in pressure drop was considered to evaluate the flow pattern in the coal matrix. Analysis was carried out to assess the effect of pressure drop on fluid velocity in the microchannel. The results of the simulations indicated an increased fluid velocity with pressure drop. Well-developed and connected microchannel was significant for transporting fluid in the coal matrix. The Simulation results were found helpful in estimating the critical pressure drop to enhance fluid flow in the microchannel of the coal matrix.