Simulation of soot aggregates formed by benzene pyrolysis

Experiments and numerical simulations were carried out to analyze the soot aggregation mechanism during benzene pyrolysis. Soot was formed by the pyro lysis of 1 mol% benzene (in 99 mol% nitrogen) in an alumina tube, which was kept at 1573K with variations of residence time (0.03 to 0.5 sec). A new cluster-cluster aggregation model called the Aggregate Mean free Path (AMP) model was developed. This model simulated the cluster-cluster aggreg ation between soot particles and aggregates using the particles or aggregat es mean free paths. The projected images of simulated soot were compared wi th the electron micrographs of experimental soot with the same magnificatio n. Simulated shape, peripheral fractal dimension and size distributions of aggregates were in good agreement with experimental data. (C) 1999 by The C ombustion Institute.