Influence of Jet Fuel Composition on Aircraft Engine Emissions: A Synthesis of Aerosol Emissions Data from the NASA APEX, AAFEX, and ACCESS Missions

Monday, 14 December 2015
Poster Hall (Moscone South)
Michael Shook1, Richard Moore2, Andreas Joel Beyersdorf2, Chelsea Corr3, Scott C. Herndon4, Walter B Knighton5, Richard C. Miake-Lye4, Kenneth Lee Thornhill II6, Edward Winstead6, Zhenhong Yu4, Luke D Ziemba2 and Bruce E Anderson2, (1)Science Systems and Applications, Inc., Lanham, MD, United States, (2)NASA Langley Research Center, Hampton, VA, United States, (3)Oak Ridge Associated Universities Inc., Oak Ridge, TN, United States, (4)Aerodyne Research Inc., Billerica, MA, United States, (5)Montana State University, Bozeman, MT, United States, (6)Science Systems and Applications, Inc. Hampton, Hampton, VA, United States
We statistically analyze the impact of jet fuel properties on aerosols emitted by the NASA McDonnell Douglas DC-8 CFM56-2-C1 engines burning fifteen different aviation fuels. Data were collected for this single engine type during four different, comprehensive ground tests conducted over the past decade, which allow us to clearly link changes in aerosol emissions to fuel compositional changes. It is found that the volatile aerosol fraction dominates the number and volume emissions indices (EIs) over all engine powers, which are driven by changes in fuel aromatic and sulfur content. Meanwhile, the naphthalenic content of the fuel determines the magnitude of the non-volatile number and volume EI as well as the black carbon mass EI. Linear regression coefficients are reported for each aerosol EI in terms of these properties, engine fuel flow rate, and ambient temperature, and show that reducing both fuel sulfur content and napththalenes to near-zero levels would result in roughly a ten-fold decrease in aerosol number emitted per kg of fuel burn. This work informs future efforts to model aircraft emissions changes as the aviation fleet gradually begins to transition toward low-aromatic, low-sulfur alternative jet fuels from bio-based or Fischer-Tropsch production pathways.