NUMERICAL MODELING OF BUBBLE DYNAMICS USING INTERFACE CAPTURING METHOD

In the present numerical study, a dynamics of single gas bubble (circular in 2D and spherical in 3D) rising in a stagnant viscous liquid due to the buoyancy is presented using various volume of fluid (VOF) based computational fluid dynamics (CFD) solvers such as commercial Converge and Star CCM+, and open source OpenFOAM^® platform. To capture the interface dynamics, either an interpolated curved interface based on the high-resolution interface framework or a mass conservative VOF approach witha planar sharp interface based geometric reconstruction ofthe piecewise-linear interface calculation (PLIC)scheme was used. Both qualitative and quantitative analysis of air bubble rising upward inside the quiescent water column at ratios of low density, ρ_r = 10 and high density, ρ_r = 1000 are simulated and evaluated similar to report by Hysing et al. The proposed numerical models can simulate a wide range of density and viscosity ratios. In this study, a robustness and accuracy of the solvers are evaluated and comparative study between open source OpenFOAM^® solver with commercial solvers such as Converge and Star CCM+. Based on the present numerical results, the gas bubble base undergoes severe deformations for the high density ratio, ρ_r = 1000 and high viscosity ratio, µ_r = 100 compared to low density ratio, ρ_r = 10 and low viscosity ratio, µ_r = 10. Any of the solvers can be used to simulate complex multiphase flow situations encountered in many industrial applications.