Aerosol Generation by Bubble Collapse at Ocean Surfaces

Sea salt particles are part ofmarine aerosols in the troposphere. A fraction ofthese particles is released by droplets generatedduring the bursting of bubbles at the ocean surface.Droplets result from fragmentation of film caps (filmdroplets) and the disintegration of water jets formedsubsequent to the bubble collapse (jet droplets).This release process is also of importance fortechnical applications and, consequently, simulationtools have been developed, which now may be used toquantify the contribution of these effects to marineaerosol generation. To calculate the amount of filmdroplets generated, it is necessary to determine thevolume of the film cap, which is a function of itsthickness and surface area. While surface areas ofsmall bubbles can be determined by an analyticalsolution of a simplified balance of forces, shapes oflarge non-spherical bubbles are calculatednumerically. The determination of the film thicknessis based on a resonance model for bubbleoscillations. For a detailed analysis of the jetdroplet generation, the bubble burst induced jetformation and disintegration is simulated numericallyusing a SOLA-MAC algorithm.