Interfacial gradient effects mass transfer coefficients

Marangoni effect is a general terra for surface flow phenomena resulting from the appearance in the interface of an interfacial tension gradient. These phenomena produce traction on the adjoining sublayers and lead to two distinct and separate effects the flux-intensive surface renewal phenomena and the area-intensive thin-film phenomena. The first phenomena predominate when the depth of the liquid is much larger than the depth of penetration of surface movement and the second are important when the two depths are comparable. In the first case the affected process parameter is the mass transfer coefficient and in the second case the interfacial area. 

---