Modelling of gas entrainment from Taylor bubbles. Part B: A stationary bubble

The model presented in Part A of this study is revised for the case of gas entrainment from a stationary bubble injected into liquid down-flow. Comparisons with data available from the literature substantiate the model as a quantitative predictive tool for the effects of bubble length, physical properties of fluids, tube diameter and inclination on the rate of gas entrainment from stationary large bubbles. milarity and differences between the fragmentation of a stationary bubble and an upward rising free bubble are discussed. It is shown that data obtained with a stationary bubble in liquid down-flow may display smaller gas entrainment rate from a similar upward rising Taylor bubble and therefore, may underestimate the aeration of the liquid bridge in slug flow.