Procedures used in electrokinetic investigations of surfactant-laden interfaces, liquid films and foam system

Electrokinetic phenomena in liquid foam media are at a junction between two well-developed fields. On the one side is the study of liquid foam drainage, which is well documented, and on the other side is electrokinetics of surface driven flow on solid-liquid interfaces, which is equally well understood. However, electrokinetic phenomena in foams with deformable air-liquid interfaces have gained significant attention only recently. In pursuit of understanding electrokinetics of foams, the model systems adopted by investigators can be summarised as: (i) free liquid films; (ii) flow cells (iii) a single bubble sandwiched between two electrodes; (iv) foam column and (v) numerical simulations. A new experimental approach for system monitoring and visualisation is proposed for foam electrokinetics. The results obtained from preliminary experiments are compared with the numerical simulations performed using Finite Element Method. The model predictions closely agree with the experimental data validating the model.