2023 Volume 88 Issue 4 Pages 259-271
Recent years, microbubble CO2 injection technology is expected to be developed in order to improve the safety and efficiency of CO2 storage. Although understanding of the microscale physical phenomena of water-microbubble CO2 flow is important for the evaluation of the microbubble CO2 injection, few quantitative analyses of its microscale flow have been conducted. In this study, numerical simulation of water-microbubble CO2 multiphase flow was conducted by considering the mass transfer of species between water and bubbles, volume change of bubbles and surface tension effect. In order to realize the temporal evolution of the water-CO2 interface, taking advantage of its easiness of setting up precise boundary conditions of the multiphase flow, we applied Arbitrary Lagrangian-Eulerian（ALE）Method which hardly had been applied in such water microbubble CO2 flow. The motion of the continuous water phase and dispersed CO2 phase were solved simultaneously by using finite element method. Our numerical simulation results showed good agreement with analytical solutions of the simple multiphase flow problems and experimental results appeared in previous researches. Through this study, we found that microbubble CO2 is dissolved into water in a very short period and CO2 in microbubble is substituted by gas such as N2 and O2 initially dissolved in water. This simulation model is of importance for understanding of the microscale physical phenomena of water-microbubble CO2 multiphase flow, since it is difficult to acquire experiment data of microscale interaction of water and microbubble CO2 in practice.
