Calculation of interfacial flows and surfactant redistribution as a gas/liquid interface moves between two parallel plates.

Autor: Wassmuth, Fred, Laidlaw, W. G., Coombe, D. A.
Předmět:
Zdroj: Physics of Fluids A; Jul93, Vol. 5 Issue 7, p1533, 16p
Abstrakt: The hydrodynamic equations governing the evolution of the interface of a gas/liquid ‘‘bubble’’ as it moves through the space between two plates are solved using a finite difference algorithm defined on a moving deforming surface grid. Particular attention is paid to the redistribution of surfactant as the bubble deforms on squeezing through a constriction. The surfactant redistribution, the surface tangential flows, and the surface normal velocity depend on factors such as bulk viscosity, the bulk/surface surfactant exchange rate, the surface tension dependence on surfactant concentration, and the bulk velocity pattern. Zones of surfactant depletion just behind the bubble front and an accumulation near the bubble front are observed; there are also depletion and accumulation zones associated with the constriction. A variety of other effects are investigated and a detailed analysis permits the generation of schematic representations of the interplay of the coupled bulk and surface hydrodynamic equations for the system. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index