Transient interaction between an oscillating bubble and a moving particle based on diffuse immersed boundary method

In this paper, the compressible two-phase fluid solver in OpenFOAM is extended to couple with the diffuse immersed boundary method, for studying the transient interaction between an oscillating bubble and a nearby freely moving particle. Similar to the volume of fluid method, the volume fraction for solid phase is used to smoothly capture the fluid–solid interface. Elimination of the explicit interpolation between the Eulerian and Lagrangian mesh is achieved with the assistance of the volume fraction. The computational domain occupied by the solid is filled with density-varying virtual fluid determined by the two-phase fluids, which guarantees the smooth numerical interpolation near the solid interface. After the verification on capability of the proposed model, the bubble–particle interaction is studied in detail. The effect of non-dimensional distance parameter on jetting dynamics and particle movement is discussed. For the case with small distance parameter, the bottom of the particle is wrapped by the expanding bubble and flow separation can be observed with disturbing bubble interface.