Experimental and Theoretical Investigation of the Effect of Dissolved Surfactant on the Dynamics of Gas Bubble Floating-up

We present the results of an experimental and numerical investigation of the floating-up of a solitary gas bubble in the presence and absence of dissolved surfactant at Reynolds numbers Re > 1. An original numerical technique is proposed, which makes it possible to investigate the dynamics of a solitary bubble with account for the effects occurring when a surfactant is introduced into the fluid. The effect of the surfactant concentration on the bubble dimensions, shape, and rise velocity are analyzed. Three stages of the bubble rise in the presence of a surfactant are established; they characterize its accumulation and distribution over the free surface of the bubble.