Sharp Front Capturing Method for Carbon Dioxide Plume Propagation during Injection into a Deep Confined Aquifer

An in-depth understanding of patterns and evolutional characteristics of carbon dioxide plume has significant implications to optimize operational strategies and manage carbon dioxide during and after injection into saline aquifers for long-term geological storage. A sharp-interface mathematical model that describes the displacement process and its interfacial dynamics of carbon dioxide-brine flow in a deep confined saline aquifer was proposed for predicting the propagation of the carbon dioxide plume. Oil the basis of a conservative level set method (LSM). the governing equation of interfacial dynamics for Capturing time-dependent fronts of the carbon dioxide plume was established. It features a unified relationship between the properties of fluids and the saturations in both the single-phase fluid regions, and the interfacial region ill the computational domain was derived by the approximation of linear fraction functions. The model equations numerically solved under different operational conditions after the effects of two adjustable parameters in the interfacial dynamics equation that determine Stable and convergent interfaces in the simulations were illustrated and analyzed. A comprehensive comparison to the Similarity solutions to a benchmark problem was made to illustrate the reliability and accuracy of the proposed approach. The simulation results show that the maximum migration distances predicted by the proposed approach are shorter than those of the similarity solutions, and the patterns and evolutional characteristics of carbon dioxide Plume are intensively dependent upon both injection durations and injection rates at the injection well. The results also show the importance of the effect of vertical mass flux in modeling the migrations of carbon dioxide plume in saline aquifers regardless of injection rates. Moreover, the influences of the underling assumptions on the interfacial dynamics of the migration of carbon dioxide were analyzed and discussed in detail. The proposed approach and the simulation results will provide insights into the determination of Optimal operational strategies and rapid identification of the consequences of carbon dioxide injection into deep confined Saline aquifers.