Numerical modeling of pulsed laser ablation of carbon particles in an aerosol

Abstract

A combined mathematical and computational model is developed for simulation of physical processes accompanying the ablation of carbon particles in an aerosol under influences of short laser pulses. The model describes absorption of laser radiation by particle material, heating and evaporation of a particle, vapor expansion into an ambient gas and formation and growth of clusters. Heating of a particle is described by the heat conduction equation. Varying of the particle's shape is taken into account. Expansion of vapor and its mixing with ambient gas are modelled by the direct simulation Monte Carlo method. Modeling of nucleation and growth of carbon nanoclusters is performed with the help of a kinetic model based on the Smolukhovskiy's rate equation. The size of carbon particles, the fluence and the duration of laser pulse are varied in computations. The influence of the particle size on the mass of the evaporated material is studied. Cluster's size distributions are obtained and analyzed. © 2007 IOP Publishing Ltd.