AAAR 34th Annual Conference
October 12 - October 16, 2015
Hyatt Regency
Minneapolis, Minnesota, USA
Abstract View
Secondary Organic Aerosol Formation from Aircraft Turbine Engine Exhaust
Dogushan Kilic, Ru-Jin Huang, Benjamin Brem, Lukas Durdina, Imad El Haddad, Felix Klein, Avi Lavi, Simone Pieber, Theo Rindlisbacher, Yinon Rudich, Jing Wang, JAY SLOWIK, Urs Baltensperger, Andre Prévôt, Paul Scherrer Institute
Abstract Number: 298 Working Group: Urban Aerosols
Abstract Aircraft engine emissions include both primary organic aerosol (POA) and volatile organic compounds (VOCs) which can react in the atmosphere to produce secondary organic aerosol (SOA). These emissions include compounds known or suspected to cause adverse health effects. While it is thus possible that airports may adversely affect local air quality, such an assessment requires detailed characterization of the primary and secondary emissions. In particular, quantitative investigation of aircraft SOA and its dependence on engine operating conditions has received little study and its atmospheric importance is poorly constrained.
We present measurements of VOCs, POA, and SOA from 7 aircraft engine models operated under simulated flight conditions representative of idling, taxiing, approach, climb, and take-off. Experiments were conducted at the SR Technics engine test facility at the Zürich International Airport. Particle composition is measured by a high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS), while the VOCs are characterized by a proton transfer reaction time-of-flight mass spectrometer (PTR-TOF-MS). SOA is produced by oxidation of engine emissions in a potential aerosol mass (PAM) flow tube and characterized as a function of OH exposure in the PAM, a surrogate for photochemical age.
VOC emissions are highest at low thrust levels and decrease by more than an order of magnitude at maximum thrust. The composition of the emissions changes, with aromatics and hydrocarbons enhanced at low thrust and a higher fraction of organic acids and carbonyls at maximum thrust. These trends correspond to changes in the SOA production potential, with the highest SOA emission factors observed at low thrust. We investigate the relationship between the emitted VOCs and produced SOA, and assess the likely influence of aircraft emissions on local air quality.