Article pubs.acs.org/EF
Demonstration of a Regulatory Method for Aircraft Engine Nonvolatile PM Emissions Measurements with Conventional and Isoparaffinic Kerosene fuels Prem Lobo,*,†,‡ Jamey Condevaux,§ Zhenhong Yu,∥ Joshua Kuhlmann,§ Donald E. Hagen,† Richard C. Miake-Lye,∥ Philip D. Whitefield,† and David W. Raper‡ †
Center of Excellence for Aerospace Particulate Emissions Reduction Research, Missouri University of Science and Technology, Rolla, Missouri 65409, United States ‡ Centre for Aviation, Transport, and the Environment, Manchester Metropolitan University, Manchester M1 5GD, United Kingdom § Williams International, 2280 East West Maple Road, Walled Lake, Michigan 48390, United States ∥ Aerodyne Research Inc., Billerica, 45 Manning Road, Billerica, Massachusetts 01821, United States ABSTRACT: The aviation industry is exploring the economic viability and environmental sustainability of the use of alternative fuels to power aircraft main engines and auxiliary power units. The International Civil Aviation Organization is also developing a regulatory standard for aircraft engine nonvolatile particulate matter (nvPM) emissions to meet the growing public demand for improvement in air quality. This study compared the nvPM emissions in the exhaust stream of a small (26.7 kN maximum rated thrust. ICAO also sets SN standards for engines 26.7 kN. In this context, nvPM is defined as the emitted particles at the aircraft engine exhaust nozzle exit plane that do not volatilize below a temperature of 350 °C. The new standard for aircraft engine nvPM emissions will align the aviation sector with other transportation modes that currently regulate PM emissions. © 2016 American Chemical Society
ICAO/CAEP is also evaluating the contribution of nvPM emissions from all aircraft engines, including those of ≤26.7 kN rated thrust, such as turboprop, turboshaft, and auxiliary power unit engines. A standard methodology for the sampling and measurement of nvPM emissions from the exhaust of aircraft engines, designed to operate in parallel with existing sampling systems for gaseous emissions and smoke certification, has been developed by the Society of Automotive Engineers (SAE) and specified in Aerospace Information Report (AIR) 6241.3 Performance evaluation and comparisons of the AIR6241 compliant systems have been successfully completed.4 The data obtained using these standardized systems will assist ICAO/ CAEP in the development of a protocol that will be used for the certification of nvPM emissions from aircraft engines, and it will also be used to better assess the impacts of aviation operations on local air quality, global climate, and health. The aviation industry, including engine manufacturers and commercial airlines, is actively exploring the economic viability and environmental sustainability of the use of alternative fuels.5 Any new fuel must be certified by the American Society for Received: June 29, 2016 Published: August 23, 2016 7770
DOI: 10.1021/acs.energyfuels.6b01581 Energy Fuels 2016, 30, 7770−7777
Article
Energy & Fuels
compartment of the heated box was maintained at 60 ± 15 °C and housed a Dekati DI-1000 ejector diluter. The nvPM sample was diluted using filtered, dry nitrogen. The dilution factor was maintained in the range 8−13, as prescribed by AIR6241.3 The diluted nvPM sample with a flow rate 25 ± 2 slpm was transferred by a temperature controlled carbon loaded PTFE sample transfer line 25 m in length, 7.9 mm i.d., maintained at 60 ± 15 °C to a 1 μm cyclone and then a second three-way splitter to direct the sample to the instrumentation in the nvPM measurement system. The nvPM emissions were characterized in terms of number, mass, size distributions, and chemical composition using realtime, high resolution instruments. The AVL Particle Counter (APC) Advanced4 was used to measure the nvPM number concentration. The APC used in this study consisted of a twostage diluter with a catalytic stripper in between to remove volatile particles, and an n-butanol-based TSI 3790E condensation particle counter (CPC) which has a >50% counting efficiency at 10 nm. The dilution in the APC was adjusted such that the nvPM number concentration measured by the CPC always remained in the single particle count mode (
