Numerical Investigation of Bubble Rising Attached to a Vertical Channel

Two-dimensional bubble rising due to gravitational forces in a channel is studied using ALE (Arbitrary Lagrangian–Eulerian) method. The dynamical behavior of the bubble is shown, and the effects of thecontact angle, Bond number, and Reynolds number areinvestigated. The main purpose of this article is to show that which kind of surface has the more bubble rising velocity and how can increase this velocity. Todo that, we first have used a finite element code and validated this code with some basic problems. Then we have solved the problem of rising bubble attached to the wetted wall in different Reynolds and Bondnumbers. The results show that on hydrophobic surface, the bubble rising velocity is more than any other walls, even more than a bubble that rises freely at the center of the channel. This is due to the drag reduction mechanism on such surfaces.

کلیدواژه ها:

Bubble Rising ، Wettability ، Drag Reduction ، Hydrophobic Surface