Marangoni Deformation During the Dry Process of Solution Film Enclosed with a Cylindrical Wall

Abstract

The dry process of a solution film enclosed with a cylindrical wall is numerically simulated to investigate the effect of solution-derived Marangoni flow on the deformation of the free surface. When no Marangoni flow occurs, drying of the liquid progresses while the free surface keeps a spherical cap. As a result, the free surface firstly reaches the center of the bottom surface, and subsequently forms a solid layer from the center toward the wall. When Marangoni flow occurs, Marangoni forces deform and flatten the free surface on the center. As the volume of the liquid decreases to 20%, cavities are developed near the wall. The cavities at a periphery of the solid layer were experimentally reported in the previous work. The calculations thus reveal the cavities results from Marangoni deformation. Moreover, the mechanism of lateral bulk flows derived by Marangoni deformation is discussed.