HIGH-SPEED VISUALIZATION OF BUBBLES INTERACTING WITH A SOLID SURFACE

摘要

Bubbles around a solid surface moving in a fluid at high Reynolds number drastically reduce the associated turbulent drag. In this paper, we present experiments on the interaction of air bubbles with a solid wall. The design of an experimental setup is described, that allows generating bubbles with diameters of 0.4 to 2 mm and observes their interaction with a solid wall whose angle with the horizontal can be controlled. Depending on the bubble size and angle of inclination of the solid wall, the bubbles bounce off or slide along the wall. High-speed visualizations of the bubble-wall interactions are performed for values of Reynolds and Weber number ranging from 40 to 560 and 0.04 to 1.80 respectively. Our experimental results are compared with the work of Tsao and Koch [Physics Fluids 9, 44 (1997)].