In homogeneous phases, the occurrence of a thermodynamic coupling between, for instance, the mass and the heat flux is well known. At interfaces the number of possible cross effects between the transport process is significantly larger than in homogeneous phases. Applying thermodynamic of irreversible processes to different models of two- and three-dimensional interfaces, it is shown that the mass transfer and the momentumtransfer can be coupled. It is deduced that there is an influence of the dilation of an interface on the mass transport across the interface. To verify this assumption, experiments are carried out in a flow cel where the plane interface between two immiscible liquids is dilated in a flow field. The fow field near the interface is measured non-intrusively using Laser-Doppler-Velocimetry. The mass transfer of a third component across the interface is measured by means of holographic interferometry. Despite the high accuracy of the optical measuring system, an effect of the dilational stress as a driving force for the mass transfer is not observedfor the systems being investigated. By calculating the entropy balance, it is concluded that presumably the effects are - if present - too small to be detectable.
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