On the phase inversion process in an oil-water pipe flow

For continuous experiments the critical concentration was found to depend on the injection phase volume fraction. The critical concentration was significantly higher for continuous experiments than for direct experiments. The change in morphological structures during phase inversion was the same for the two types of experiments. During inversion the concentration of drops of the (originally) dispersed phase becomes so high, that they coalesce at certain places in the flow field and form relatively large, rather complex, morphological structures. With a further increase in concentration of the (originally) dispersed phase these morphological structures grow in size and start to form the new continuous phase in which again complex structures are present, but this time consisting of the (originally) continuous phase.