Bubble curtain for blocking spilled oil on water surface

For protecting important port facilities such as emergency evacuation bases from oil spill incident triggered by natural disasters, some self-sufficient countermeasures are required for blocking or eliminating floating oil from the facilities. For this purpose, bubble curtain was studied. The bubble curtain itself already has some preceding researches or applications for containment of floating oil, most of all, however, deals with the phenomena in open sea. This paper especially focuses on the bubble curtain deployed near a vertical wall, intended for application to protecting land facilities. Experimental measurements using video processing were carried out in a test tank to see how large oil-free area the bubble curtain can generate. The experimental results were analyzed and arranged to a simple empirical equation providing the size of oil free area. 2-D and 3-D Numerical simulations using OpenFOAM was also conducted for verifying the experimental results and for deeper understanding of air-water multiphase physics. This paper also includes discussion about the horizontal velocity field that the bubble promotes near the water surface and comparison with some previous studies.