In this article, the effect of the size bin resolution in a discrete aeroso
l dynamic model which predicts the formation of particles in an aircraft pl
ume is examined. The model includes plume dilution and both the effect of n
eutral and charged particles on coagulation, with coefficients which vary w
ith particle size and charge. A comparison of the model results is made wit
h the in-flight experimental data collected in the plume of the ATTAS aircr
aft during the SULFUR-5 mission (Schroder et al., 1998). From this comparis
on, it appears that the choice of the value to be used for the "volume rati
o" in the coagulation scheme is crucial to correctly determine the size dis
tribution of the particles, especially for the larger sizes, as well as the
emission indices for volatile particles, (C) 2001 Elesvier Science Ltd. Al
l rights reserved.