A CFD-based approach to the interfacial mass transfer at free gas–liquid interfaces

A novel computational fluid dynamics (CFD) based approach is suggested, which incorporates interfacial mass transfer at moving interfaces. This approach is general and able to govern multicomponent systems as well as interfacial boundary conditions in an arbitrary form. This is important in order to properly handle the typical concentration jump at the phase interface and to avoid an assumption of a constant distribution coefficient, which is seldom met in real processes. A test case study is carried out for a gas bubble rising in a stagnant liquid phase, whereas two different liquids, namely water and water–carboxymethylcellulose solution, are used. The gas bubble contains 99% of oxygen diffusing into continuous phase. The movement of the bubble is simulated using the level set method. Both velocity vectors and concentration contours are demonstrated and analysed.