RESUMO

Interfacial friction shows an important influence on the predictions of two-fluid model. This study discusses a few simple situations, such as one-dimensional and steady flow conditions for which correlations for interfacial frictions have been well established. Empirical terms derived from specified experiments are found necessary due to the impossibility of describing all the details of flows (e.g. interface geometry and phase interactions). More works are needed in future to develop more systematic methods and models representing the physics of the flows, and data banks containing measurements of enough parameters are then required.