Surface rheology

Surface rheology is a description of the rheological properties of a free surface. When perfectly pure, the interface between fluids usually displays only surface tension. The stress within a fluid interface can be affected by the adsorption of surfactants in several ways:

• Change in the surface concentration of surfactants when the in-plane flow tends to alter the surface area of the interface (Gibbs' elasticity).
• Adsorption/desorption of the surfactants to/from the interface.