Identification of secondary aerosol precursors emitted by an aircraft turbofan


Kilic D., El Haddad I., Brem B. T. , Bruns E., Bozetti C., Corbin J., ...More

ATMOSPHERIC CHEMISTRY AND PHYSICS, vol.18, no.10, pp.7379-7391, 2018 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 18 Issue: 10
  • Publication Date: 2018
  • Doi Number: 10.5194/acp-18-7379-2018
  • Title of Journal : ATMOSPHERIC CHEMISTRY AND PHYSICS
  • Page Numbers: pp.7379-7391

Abstract

Oxidative processing of aircraft turbine-engine exhausts was studied using a potential aerosol mass (PAM) chamber at different engine loads corresponding to typical flight operations. Measurements were conducted at an engine test cell. Organic gases (OGs) and particle emissions pre- and post-PAM were measured. A suite of instruments, including a proton-transfer-reaction mass spectrometer (PTRMS) for OGs, a multigas analyzer for CO, CO2, NO x, and an aerosol mass spectrometer (AMS) for nonrefractory particulate matter (NR-PM1) were used. Total aerosol mass was dominated by secondary aerosol formation, which was approximately 2 orders of magnitude higher than the primary aerosol. The chemical composition of both gaseous and particle emissions were also monitored at different engine loads and were thrust-dependent. At idling load (thrust 2.57 %), more than 90% of the secondary particle mass was organic and could mostly be explained by the oxidation of gaseous aromatic species, e.g., benzene; toluene; xylenes; tri-, tetra-, and pentamethyl-benzene; and naphthalene. The oxygenated-aromatics, e.g., phenol, furans, were also included in this aromatic fraction and their oxidation could alone explain up to 25% of the secondary organic particle mass at idling loads. The organic fraction decreased with thrust level, while the inorganic fraction increased. At an approximated cruise load sulfates comprised 85% of the total secondary particle mass.