Reconstruction of combustion particles by adsorption of volatile material

摘要

Particles in the exhaust of combustion engines mainly consist of elemental carbon and a variety of volatile species,being either condensed on the particles or nucleating to form new particles,when the exhaust gas cools down.Mainly spark ignition engines produce a high fraction of volatile material.Already in the hot zone these particles start to coagulate and form chain or grapelike agglomerates.In many cases the condensation of volatile material only starts when the agglomeration process is already in an advanced state.In the experiments described here the influence of condensation on the structure of the agglomerates has been investigated.This was done by measuring the change in size of an agglomerate when condensing material on.In a subsequent step this material is removed.In addition,the condensation process was monitored by a photoelectric aerosol sensor (PAS).