Characterization of Emissions From the Use of Alternative Aviation Fuels

Abstract

Alternative fuels for aviation are now a reality. These fuels not only reduce reliance on conventional petroleum-based fuels as the primary propulsion source, but also offer promise for environmental sustainability. While these alternative fuels meet the aviation fuels standards and their overall properties resemble those of the conventional fuel, they are expected to demonstrate different exhaust emissions characteristics because of the inherent variations in their chemical composition resulting from the variations involved in the processing of these fuels. This paper presents the results of back-to-back comparison of emissions characterization tests that were performed using three alternative aviation fuels in a GE CF-700-2D-2 engine core. The fuels used were an unblended synthetic kerosene fuel with aromatics (SKA), an unblended Fischer Tropsch synthetic paraffinic kerosene (SPK) and a semi-synthetic 50-50 blend of Jet A-1 and hydroprocessed SPK. Results indicate that while there is little dissimilarity in the gaseous emissions profiles from these alternative fuels, there is however a significant difference in the particulate matter emissions from these fuels. These differences are primarily attributed to the variations in the aromatic and hydrogen contents in the fuels with some contributions from the hydrogen-to-carbon ratio of the fuels.

Characterization of the Fine Particle Emissions from the Use of Two Fischer–Tropsch Fuels in a CFM56-2C1 Commercial Aircraft Engine

“…10,14,17,19 Most other data were collected near the engine exit using a sampling protocol which does not capture the volatile sulfur and organic particles formed in the downstream plume. [6][7][8][9][10][11][12][14][15][16][18][19][20][21]23 In addition, some data sets only provide normalized EIs rather than actual emissions, thus further restricting their usefulness for comparison to other work. Table S4 in the Supporting Information shows the emissions reductions associated with the use of the FT jet fuels and blends evaluated in our study as compared to other alternative fuel measurements reported in the literature.…”

Particle emissions of two unblended alternative jet fuels in a full scale jet engine

“…Total particle number (A) and particle mass (B) emission index for the different thrust settings and fuels (EEPS, 5.6 -200 nm).It must be noted that the impact of the fuel composition on the particle reduction potential is strongly depending on the jet engine used. Chan et al[27] used a GE CF-700-2D-2 turbofan engine (20 kN) for testing the emissions from three different alternative fuels in comparison to regular Jet A-1. Their fuels "CH-SKA" and "FT-SPK" are chemically comparable to the ReadiJet and ATJ fuels of this experiment.…”