EFFECTS OF ETHANOL ADDITION IN AN ETHYLENE/AIR FLAME ON THE PRIMARY AND SECONDARY PARTICLE SIZE DISTRIBUTION

The aim of this study is to investigate the effects of the introduction of different ethanol concentrations in a premixed ethylene/air flame. The impact of the ethanol addition is studied in terms of primary (PA) and secondary aerosol (SA) formation through the analysis of particle size distribution functions (PSDs). The PSDs of doped and undoped flames are collected through a scanning mobility particle size (SMSP) system at different heights above the burner (HAB), i.e. different residence times. Different ethanol concentrations, equal to 10% and 20%, were used to dope the flame in order to replicate commercial mixtures available on the national market. The secondary aerosol formation process is replicated through the use of an Oxidation Flow Reactor developed by Dekaty® (DOFRTM) and an ozone flux, applied to the main stream, in order to simulate an atmospheric aging time of two days. The comparison among the pre-mentioned conditions is performed so to highlight the presence of trends in PSDs functions and to crosscheck if the ethanol addition decreases the emissions in terms of both PA and SA.