Measurement of Emissions from Jet Engines and Other Combustion Sources Using the Engine Soot Compliance Monitor (ESCoM)
Abstract
The International Civil Aviation Organization (ICAO) has set emissions standards for non-volatile PM (nvPM) emissions, primarily light absorbing carbon, from aircraft engines. It relies on the SAE E-31 Committee to draw up specific technical standards for the measurement of these emissions as well as certification procedures for nvPM emission monitors. Currently, two instruments have been certified as meeting the committee's criteria - one utilizes photoacoustic absorption spectroscopy and the other laser induced incandescence. In order to meet the need for another measurement approach, Aerodyne Research is developing the Engine Soot Compliance Monitor (ESCOM) based on its CAPS PMssa monitor.
CAPS PMssa monitors provide simultaneous measurement of both particle extinction and scattering on the same sample volume (and thus particle absorption) with great sensitivity (0.1 ug m-3) and accuracy. The mass concentration of nvPM is obtained by dividing the measured absorption by a representative mass absorption coefficient (MAC), such as for mature soot. This approach offers the potential for being based on an absolute particle standard rather than a comparison to the Sunset Laboratory OC/EC Analyzer (the current standard). The ESCOM, which combines an internal carbon dioxide sensor with the CAPS PMssa, provides a real time measurement of the nvPM emission index (a measure of the amount of nvPM emitted per kg of fuel expended) if the chemical composition of the fuel is known. We will present results from the NASA/DLR-sponsored ND-MAX campaigns which involved measurements of nvPM emissions from a test-bed mounted engine and from an Airbus A320, respectively, using a version of the monitor which operated at 630 nm. These tests involved various types of biofuel mixtures as well as standard jet fuel. We will also describe a new version, which operates at 780 nm, thus avoiding an interference posed by high concentrations of nitrogen dioxide in engine emissions. Results from our new ESCOM instrument, collected during the EPA-sponsored (in collaboration with U.S. Air Force AEDC) VARIAnT4 campaign which included calibration and certification tests, will be shown as well.- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFM.A32A..05F
- Keywords:
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- 0305 Aerosols and particles;
- ATMOSPHERIC COMPOSITION AND STRUCTURE;
- 0321 Cloud/radiation interaction;
- ATMOSPHERIC COMPOSITION AND STRUCTURE;
- 0345 Pollution: urban and regional;
- ATMOSPHERIC COMPOSITION AND STRUCTURE;
- 6344 System operation and management;
- POLICY SCIENCES & PUBLIC ISSUES