Shadab Anwar
Valencia College, USA
Title: Lattice Boltzmann modeling of buoyant rise of single and multiple bubbles
Biography
Biography: Shadab Anwar
Abstract
Buoyancy induced bubble dynamics is investigated using the Gunstensen color model based on the lattice Boltzmann method. A source term is incorporated in the collision term to simulate buoyant rise of bubble under gravitational force. The shape of bubble is controlled by inertial, viscous and surface tension forces. The interplay between these forces is quantified using non-dimensional numbers such as Eötvös number (Eo), Morton number (Mo) and Reynolds number (Re). The shape of bubble in various flow regimes, characterized by the non-dimensional numbers, is compared against the experimental data. The effect of surface tension and viscosity ratio on terminal velocity and shape of bubble is investigated. The LBM results for change in shape of bubble or circularity of bubble is compared against COMSOL. Co-axial and oblique coalescence of two gas bubbles are simulated and compared against the experimental data. The LBM result was found to be in good agreement with the analytical solution, the experimental data and the COMSOL simulation.
The buoyancy model is applied to investigate the impact of capillary, buoyancy, and viscous forces on the displacement of brine by supercritical CO2 at the pore scale. The effect of these forces on residual brine will be quantified in terms of non-dimensional numbers such as Bond number (Bo), Viscosity ratio (M), and Reynolds number (Re). This can help us predict the storage capacity of a given aquifer for given physical properties of CO2 and brine. The density contrast between brine and CO2 ranges from 1.3 to 4.5 and the viscosity contrast ranges from 5 to 40.