Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : November 11, 2020 - November 13, 2020
The drainage and rupture of the thin liquid film formed between a bubble and a flat mica plate have been investigated. It is known that the bubble coalescence can be prevented in electrolyte aqueous solution, and its effects strongly depends on the type of electrolyte. In this study, by using two types of electrolyte aqueous solutions (0.05 M MgSO4 aqueous solution and 0.05 M CH3COONa aqueous solution) and surfactant aqueous solution (10 ppm Triton X-100 aqueous solution), the effects of impurities in water on the behavior of the liquid thin film and the effect of the approaching velocity of bubble toward the mica plated have been evaluated. By using an optical interferometer and a high-speed video camera, interference fringe patterns can be observed and the shape of the liquid thin film formed between a bubble and a flat mica plate can be obtained. There was almost no difference in the rim width and depth between the case with two electrolyte aqueous solutions, while the increase in the rim width was suppressed and the depth became smaller in case with Triton X-100 aqueous solution due to the Marangoni effect. The rim width and depth tend to increase as the bubble approaching velocity increase in every solutions.
