Abstract
By utilizing the optical Schlieren method, Marangoni convection produced in different gas–liquid mass transfer processes was observed and recorded. Different liquid solvent mixtures were selected to investigate the flow patterns of the Marangoni convection as well as the driven mechanism of the surface tension gradient. Unordered flow patterns were observed frequently in experiments, and it is different from ordinary orderly Marangoni flow patterns such as regular roll and cellular flow patterns. Qualitative analysis of flow patterns in mass transfer was made through the Schlieren images observed, and in consequence a scaling analysis was made to discuss the relationship between the Marangoni effect and the unusual mass transfer performance. By combining the Marangoni hydraulic boundary condition with the penetration theory of mass transfer, the Marangoni number characterizing the intensity of Marangoni effect enters the conventional mass transfer correlation. The quantitative result successfully explains these different correlations between Sh and Ma obtained in mass transfer processes accompanied by the Marangoni effect.
