Dynamics of Ostwald Ripening with Coalescence

摘要

Numerous studies have been concerned with the asymptotic stages of growth by condensation/evaporation of droplets or particles following their appearance by a homogeneous nucleation process. Comparatively less attention has been given the associated problem of growth when both condensation/evaporation and coalescence occur. For aerosols we present the first quantitative study of the Ostwald ripening problem with a realistic coalescence process. We have investigated the isothermal spatially homogeneous growth of particles suspended in supersaturated monomer vapor and inert host gas. Numerical results of the Ostwald Ripening problem with coalescence are reported for aerosol with the continuum diffusive growth laws. It was shown that N(t) approx. t-1, where N(t) is the total number concentration. These results, though consistent with the asymptotic theory of Ostwald Ripening according to Lifshitz-Slyozov and with the similarity theory for the continuum Brownian coalescence process, show that the scaling arguments are insufficient to establish which of the two mechanisms is dominant asymptotically.