MARANGONI CONVECTION DURING STEAM ABSORPTION INTO AQUEOUS LIBR SOLUTION WITH SURFACTANT

The Marangoni convection during steam absorption into aqueous LiBr solution with a small amount of surfactant was observed by Schlieren photography, and the surface tension of the absorbing solution was measured to investigate the mechanism of the convection. Also, a numerical simulation of the Marangoni convection was carried out. It is found experimentally that the surface tension of LiBr solution with surfactant decreases with increasing LiBr concentration and that the Marangoni convection in this system is not essentially induced by the presence of surfactant islands on the surface of the solution as proposed by the previous workers, but is in accordance with the general criterion of Marangoni instability. The calculated results could simulate qualitatively the initiation and growth of convection in this system.