Isothermal dissolution of small rising bubbles in a low viscosity liquid

The isothermal dissolution of small single rising bubbles in a low viscosity liquid is numerically and experimentally studied. We propose a tracking-interface numerical method to analyze the dissolution of single bubbles rising in an isothermal liquid bath in the limit of small Weber numbers. The key elements of the method are the use of a frame of reference moving with the bubble and the application of different meshes to solve the mechanical and mass-diffusion problems. In addition, the gas concentration in the atmosphere over the bath, determined by mass balance of species in the gas column, is shown to be an essential component of the global dissolution problem in steady regime. Comparison with small oxygen bubbles rising in water has been carried out with remarkable agreement.