Oscillation of a transient bubble near an aperture made in a convex rigid plate

Abstract

Bubble dynamics near a convex plate with and without a hole is investigated using boundary element method. First, the effects of bubble-hole distance (standoff distance) on the bubble behavior for the convex plate without a hole are determined. Then for the perforated convex plate the effects of standoff distance and the hole diameter on the bubble dynamics are studied. The pressure field and velocity vectors of the fluid surrounding the bubble are provided for better interpretation of the results. Finally, a general classification of the bubble behavior during its collapse phase near the perforated convex plate is presented based on the hole size and the standoff distance. For small standoff distances, during the growth phase, a bump will form on the bubble surface which is closer to the hole. The behavior of the bubble changes if the standoff distance or the hole size are changed. In general, based on the relative value of the two parameters of standoff distance and hole size, four distinctive scenarios of the bubble oscillation can be recognized: (I) two simultaneous jets, (II) a jet directing towards the hole, (III) a jet directing away from the hole (IV) oscillation of the bubble without any jetting induced.