Simulation of particle agglomeration and fragmentation in a low gravity environment

Abstract

We are developing simulation tools to design aerosol experiments in a space environment. The simulations will be used to assess trade-offs among the level of gravity, active experimental volume, particle density and primary particle size. In our previous work [1] we simulated the formation of particle clusters in a low gravity environment using a modified version of the CONTAIN code [2]. The model did not include the effect of cluster fragmentation on the particle size distribution and deposition on the cell walls. Before implementing complex modifications to the CONTAIN code we have investigated the effects of fragmentation using the Monte Carlo (MC) method to simulate aerosol dynamics. The constant-N Monte Carlo method developed by the Matsoukas group [3–5] was used. In this method the number of particles in the system is kept constant and the mean cluster volume is increased or decreased depending on the event (fragmentation, agglomeration,…). We are particularly interested in measuring the average volume of clusters and probability, Pk, of finding a cluster containing k primary particles. Both quantities are measurable in a low microgravity experiment. Results are presented for different levels of gravity, particle density and fragmentation kernel. The results demonstrate the potential benefits of a full simulation of the planned experiments.