Recent advances in gas turbine combustor design are aimed at achieving low exhaust\nemissions, hence modern aircraft jet engines are designed with lean-burn combustion systems.\nIn the present work, we report an experimental study on lean combustion in a liquid fuel burner,\noperated under a non-premixed (single point injection) regime that mimics the combustion in a\nmodern aircraft engine. The flame behavior was investigated in proximity of the blow-out limit by an\nintensified high rate Charge-Coupled Device (CCD) camera equipped with different optical filters to\nselectively record single species chemiluminescence emissions (e.g., OH*, CH*). Analogous filters\nwere also used in combination with photomultiplier (PMT) tubes. Furthermore this work investigates\nwell-mixed lean low NOx combustion where mixing is good and generation of solid carbon particulate\nemissions should be very low. An analysis of pollutants such as fine particles and gaseous emissions\nwas also performed. Particle number concentrations and size distributions were measured at the\nexhaust of the combustion chamber by two different particle size measuring instruments: a scanning\nmobility particle sizer (SMPS) and an Electrical Low Pressure Impactor (ELPI). NOx concentration\nmeasurements were performed by using a cross-flow modulation chemiluminescence detection\nsystem; CO concentration emissions were acquired with a Cross-flow modulation Non-dispersive\ninfrared (NDIR) absorption method. All the measurements were completed by diagnostics of the\nfundamental combustor parameters. The results herein presented show that at very-lean conditions\nthe emissions of both particulate matter and CO was found to increase most likely due to the\noccurrence of flame instabilities while the NOx were observed to reduc
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