Population balance modelling of isothermal bubbly-cap flows using two-group averaged bubble number density approach

Considerable attention has been concentrated on describing the temporal and spatial evolution of two-phase geometrical structure caused by the effects of bubble interactions in gas-liquid flows. In the published literature, the transport phenomena of dispersed bubbles in bubbly flow conditions can be regarded in a similar view of the drag and interaction of spherical bubbles, which have brought about the development of most coalescence and break-up mechanisms based primarily on the assumption of interaction between such bubbles. Nevertheless, cap bubbles which are precursors to the formation of slug units in the slug flow regime with increasing volume fraction become ever more prevalent at high gas velocity conditions.