Simulation of bubble dynamics near a plate with an aperture in a vertical cylinder using a combined boundary element-finite difference method

Bubble dynamics near a perforated plate in a vertical cylinder is investigated using a combined boundary element-finite difference method. First, we determined the critical cylinder diameter for which the cylinder wall would not affect the bubble dynamics. Then for the case without cylinder wall effect, the effects of plate hole size and the bubble-hole distance were studied. Finally, the simultaneous effect of plate hole and cylinder diameter on the bubble behavior was evaluated. It was found that, for normalized bubble-hole distances H' <= 0.8, there is only a liquid jet from the bottom surface of the bubble directing away from the hole, which becomes stronger as the normalized hole size d' is decreased. For H' >= 1.8, there is only a liquid jet from the top surface of the bubble directing toward the hole, which becomes stronger as the hole size d' is decreased. For 0.8 < H' < 1.8, there are two liquid jets from both the top and the bottom surface of the bubble, which depending on the bubble-hole distance, one of these jets becomes stronger as the hole size is decreased. In addition, smaller cylinder diameter would prolong the lifetime of the bubble. (C) 2015 Elsevier Ltd. All rights reserved.