n many chemical and biochemical processes, mass transfer between gas and liquid phases plays a crucial role. Gaseous species are often introduced into the system as bubbles, with mass transfer occurring at the bubble surfaces. Processes such as bubble breakup and coalescence significantly affect the total surface area and, consequently, the mass transfer rate. Other influencing factors include boundary layer thickness and local concentration gradients, which drive the transfer through differences in chemical potential.

This work focuses on the development, implementation, and validation of a new model to describe gaseous bubble breakup. A trajectory-based approach is used, modeling each bubble individually as a Kelvin-Voigt element, and assuming that bubbles behave like rotating ellipsoids. Surface tension is represented as a theoretical spring pulling the bubble toward its equilibrium (spherical) shape, while gas viscosity is modeled as a damper resisting deformation. The deformation itself is described using a Lagrangian analysis of the local fluid-induced stretching.

Bubble breakup is determined by comparing the surface tension force, reduced by deformation, to inertial forces such as drag. Initially, drag is approximated by buoyancy, but this simplification ignores varying flow conditions. Therefore, a more accurate drag force formulation is derived to improve the model.

Both model versions are tested using Lattice Boltzmann simulations. The resulting bubble sizes are used to calculate mass transfer via either penetration theory or a Sherwood correlation, and the results are validated against experimental data.