ABSTRACT. A novel approximate theoretical analysis is proposed whereby the deposition of aerosols in expanding and shrinking spherical bubbles rising in stagnant liquid due to the combined effects of molecular diffusion, convection, and inertia is modeled. The bubble internal circulation is assumed to be similar to Hill's vortex flow.Using the new method, parametric calculations representing conditions where bubbles remain spherical and nonoscillating, and diffusion, convection, and inertia are the dominant aerosol removal mechanisms, are performed, and the contribution of the inertial transport mechanism is discussed. It is also suggested that the common practice of using Fuchs's methodology, where aerosol fluxes resulting from different mechanisms are separately calculated using simple models and added together to find the total aerosol flux, is inadequate.

In the present work, an unified derivation of simple evaporation models used in spray simulation is described and a new evaporation model is formulated. In the model, the Nusselt number, Sherwood number, and evaporation mass flux are derived using the traditional film theory. However, instead of determining the film thicknesses using the Nusselt and Sherwood numbers derived in the absence of high mass transfer rate, the film thicknesses are calculated from those derived from the fully numerical solutions which represent the realistic heat and mass transfer processes around a droplet. The model predictions are compared with the fully numerical solutions.

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