Simulation of the three-dimensional behavior of an unsteady large bubble near a structure

Abstract

In most practical applications existing bubble dynamics models, either spherical or axisymmetric, are only more or less appropriate approximations. In this paper we will describe an on‐going project which considers the fully three‐dimensional bubble dynamics problem. The interaction between a growing, deforming and collapsing bubble near a boundary is simulated numerically using a Boundary Integral Method. The example of large bubble dynamics near a solid flat plate in a gravity field is considered. The plate orientation significantly influences the 3‐D bubble shape and behavior. The flow field due to the bubble dynamics is considered to be potential. To initialize the computations, the bubble is taken to be very small and spherical. From there on, no additional assumptions are imposed and the bubble surface is free to move under the influence of the pressure field, inertia forces, and the presence of body forces and a nearby wall. The presence of gas inside the bubble is accounted for using a polytropic law of behavior and surface tension is included in the model. This paper presents the method, addresses the numerical difficulties and shows the influence of the problem geometry on the bubble dynamics.