| Abstract: | Linear stability analysis is applied to the absorption of water vapor into lithium bromide aqueous solution film when a small amount of surfactant is added to the solution. The condition under which an instability occurs and the role of the surfactant are investigated. The analysis shows that the film becomes unstable at a positive Marangoni number when the heat transfer is more determining than the mass transfer. In contrast, when the mass transfer is more determining, the film becomes unstable at a negative Marangoni number. As for LiBr aqueous solution, mass transfer is more rate determining than heat transfer, so the instability is promoted and maintained when the Marangoni number is negative. In the case of film flow absorption, the analysis shows that the disturbance of the film flow becomes more unstable in the transverse direction than in the longitudinal direction as the Reynolds number increases. © 2000 Scripta Technica, Heat Trans Asian Res, 29(7): 581–597, 2000 |
