Numerical simulation of a 2D bubble curtain: exploring Coastal Engineering applications.

This work was motivated by a Coastal Engineering problem: nearshore sediment transport caused by marine currents and waves tend to block navigation in marine seaports and harbors. The perspective of a mechanism that could keep the sediment in suspension given the added momentum and mixing due to a bubble curtain is very attractive. There are several studies that consider point and line source bubble curtains, however there are very few studies that consider hydrodynamic interactions with currents and waves. As a result of this knowledge gap, a numerical study of a 2D bubble curtain in a confined reservoir was carried out using the OpenFOAM(TM) finite volume (VoF) code. Three cases were considered: interaction between the bubble curtain and quiescent fluid, bubble curtain and currents, bubble curtain and waves, and finally bubble curtain with currents and waves. The recirculation caused by the bubble curtain and its range of influence, as well as the induced velocities for different air flow rates were discussed, as well as the effect of the bubble wall on the wave components and energy. The presence of the bubble wall can influence the hydrodynamics and consequently the sediment transport, which has to be further studied in the near future.