title: Determination of the emissions from an aircraft auxiliary power unit (APU) during the Alternative Aviation Fuel Experiment (AAFEX).
abstract: The emissions from a Garrett-AiResearch (now Honeywell) Model GTCP85-98CK auxiliary power unit (APU) were determined as part of the National Aeronautics and Space Administration's (NASA's) Alternative Aviation Fuel Experiment (AAFEX) using both JP-8 and a coal-derived Fischer Tropsch fuel (FT-2). Measurements were conducted by multiple research organizations for sulfur dioxide (SO2, total hydrocarbons (THC), carbon monoxide (CO), carbon dioxide (CO2), nitrogen oxides (NOx), speciated gas-phase emissions, particulate matter (PM) mass and number, black carbon, and speciated PM. In addition, particle size distribution (PSD), number-based geometric mean particle diameter (GMD), and smoke number were also determined from the data collected. The results of the research showed PM mass emission indices (EIs) in the range of 20 to 700 mg/kg fuel and PM number EIs ranging from 0.5 x 10(15) to 5 x 10(15) particles/kg fuel depending on engine load and fuel type. In addition, significant reductions in both the SO2 and PM EIs were observed for the use of the FT fuel. These reductions were on the order of approximately 90% for SO2 and particle mass EIs and approximately 60% for the particle number EI, with similar decreases observed for black carbon. Also, the size of the particles generated by JP-8 combustion are noticeably larger than those emitted by the APU burning the FT fuel with the geometric mean diameters ranging from 20 to 50 nm depending on engine load and fuel type. Finally, both particle-bound sulfate and organics were reduced during FT-2 combustion. The PM sulfate was reduced by nearly 100% due to lack of sulfur in the fuel, with the PM organics reduced by a factor of approximately 5 as compared with JP-8.
authors.affiliation: U.S. Environmental Protection Agency, Office of Research and Development, National Risk Management Research Laboratory, Research Triangle to Park, NC 27711, USA. kinsey.john@epa.gov
authors.forename: John S
authors.initials: JS
authors.lastname: Kinsey
authors.forename: Michael T
authors.initials: MT
authors.lastname: Timko
authors.forename: Scott C
authors.initials: SC
authors.lastname: Herndon
authors.forename: Ezra C
authors.initials: EC
authors.lastname: Wood
authors.forename: Zhenhong
authors.initials: Z
authors.lastname: Yu
authors.forename: Richard C
authors.initials: RC
authors.lastname: Miake-Lye
authors.forename: Prem
authors.initials: P
authors.lastname: Lobo
authors.forename: Philip
authors.initials: P
authors.lastname: Whitefield
authors.forename: Donald
authors.initials: D
authors.lastname: Hagen
authors.forename: Changlie
authors.initials: C
authors.lastname: Wey
authors.forename: Bruce E
authors.initials: BE
authors.lastname: Anderson
authors.forename: Andreas J
authors.initials: AJ
authors.lastname: Beyersdorf
authors.forename: Charles H
authors.initials: CH
authors.lastname: Hudgins
authors.forename: K Lee
authors.initials: KL
authors.lastname: Thornhill
authors.forename: Edward
authors.initials: E
authors.lastname: Winstead
authors.forename: Robert
authors.initials: R
authors.lastname: Howard
authors.forename: Dan I
authors.initials: DI
authors.lastname: Bulzan
authors.forename: Kathleen B
authors.initials: KB
authors.lastname: Tacina
authors.forename: W Berk
authors.initials: WB
authors.lastname: Knighton
mesh_terms: D000393:Air Pollutants / Q000737:chemistry*; D000401:Aircraft; D003031:Coal; D059206:Natural Gas; D010316:Particle Size; D052638:Particulate Matter; D010578:Petroleum; D001335:Vehicle Emissions / Q000032:analysis*
chemical_list: D000393:Air Pollutants; D003031:Coal; D059206:Natural Gas; D052638:Particulate Matter; D010578:Petroleum; D001335:Vehicle Emissions