This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Evolution in Size and Morphology of Diesel Particulates Along the Exhaust System
Technical Paper
2004-01-1981
ISSN: 0148-7191, e-ISSN: 2688-3627
This content contains downloadable datasets
Annotation ability available
Sector:
Language:
English
Abstract
The physical and morphological properties of the particulate matter emitted from a 1.7-liter light-duty diesel engine were characterized by observing its evolution in size and fractal geometry along the exhaust system. A common-rail direct-injection diesel engine, the exhaust system of which was equipped with a turbocharger, EGR, and two oxidation catalysts, was powered with a California low-sulfur diesel fuel at various engine-operating conditions. A unique thermophoretic sampling system, a high-resolution transmission electron microscope (TEM), and customized image processing/data acquisition systems were key instruments that were used for the collection of particulate matter, subsequent imaging of particle morphology, and detailed analysis of particle dimensions and fractal geometry, respectively. The measurements were carried out at four different positions along the exhaust pipe. The rapid insertion of sampling probe into the exhaust stream, whose residence time resolves as short as 10 msec, provided near interference-free sampling of diesel particulates. From analyses for the soot samples collected at 2500-rpm and 25%-load, it was revealed that the primary particle diameter decreased from 28.6 nm to 19.1 nm and the corresponding radius of gyration of aggregate particles also decreased from 101.6 nm to 49.6 nm along the exhaust pipe. This reduction of particle sizes implies that particle sizes are significantly affected by aftertreatment components in the exhaust system. The detailed fractal analysis supported this finding; a fractal dimension of particles was slightly higher right after the first catalyst than those evaluated at other sampling positions, which indicates that particles became more spherical in shape during passing through the first catalyst. The fractal dimensions varied in a range of 1.5 to 1.7 along the exhaust pipe. It is speculated that the catalytic oxidation and aerodynamics of exhaust streams were major parameters influencing the distributions of measured sizes and fractal geometry. A chemical analysis using energy dispersion spectroscopy revealed that diesel particulates consist of elemental carbons in most portions.
Recommended Content
Topic
Citation
Lee, K. and Zhu, J., "Evolution in Size and Morphology of Diesel Particulates Along the Exhaust System," SAE Technical Paper 2004-01-1981, 2004, https://doi.org/10.4271/2004-01-1981.Data Sets - Support Documents
| Title | Description | Download |
|---|---|---|
| Unnamed Dataset 1 |
Also In
References
- Lahaye, J. Prado, G. “Soot in Combustion Systems and Its Toxic Properties,” NATO Conference Series VI:7 Plenum Press New York 1983
- Keane, M.J. Xing, S.-G. Harrison, J.C. Ong, T. Wallace, W.E. “Genotoxicity of diesel-exhaust particles dispersed in simulated pulmonary surfactant,” Mutation Research 260 233 238 1991
- Wallace, W.E. Keane, M.J. Hill, C.A. Xu, J. Ong, T. “Mutagenicity of Diesel Exhaust Particles and Oil Shale Particles Dispersed in Lecithin Surfactant,” J. of Toxicology and Environmental Health 21 163 171 1987
- Vuk, C.T. Jones, M.A. Johnson, J.H. “The Measurement and Analysis of the Physical Character of Diesel Particulate Emissions,” SAE 760131
- Baumgard, K.J. Kittelson, D.B. “The Influence of a Ceramic Particle Trap on the Size Distribution of Diesel Particulates,” SAE 850009
- Abdul-Khalek, I.S. Kittelson, D.B. Graskow, B. R. Wei, Q. Brear, F. “Diesel Exhaust Particle Size: Measurement Issues and Trends,” SAE 980525
- Lee, K.O. Zhu, J. Ciatti, S. Yozgatligil, A. Choi, M “Sizes, Graphitic Structures and Fractal Geometry of Light-Duty Diesel Engine Particulates,” SAE 2003-01-3169
- Zhu, J. Lee, K.O. Sekar, R. Choi, M. “Morphological Study of the Particulate Matter from a Light-Duty Diesel Engine,” 3 rd Joint Meeting of the U.S. Section of the Combustion Institute Chicago, IL March 17-19 2003
- Lee, K.O. Zhu, J. Sekar, R. Yozgatligil, A. Choi, M. “Characterization of Particulate Sizes, Microstructures, and Fractal Geometry of a Light Duty Diesel Engine via Thermophoretic Sampling,” 13 th CRC On-Road Vehicle Emissions Workshop San Diego, CA April 7-9 2003
- Personal communication with Prof. Megaridis University of Illinois Chicago
- HCCI Panel at the SAE Powertrain & Fluid Systems Conference & Exhibition Pittsburgh October 27-30 2003
- Lee, K.O. Cole, R. Sekar, R. Choi, M.Y. Kang, J Bae, C.S. Shin, H.D. “Morphological Investigation of the Microstructure, Dimensions, and Fractal Geometry of Diesel Particulates,” 29 th Proc. Comb. Inst. 2002
- Schaefer D. W. “Fractal Models and the structure of Materials,” MRS Bulletin 13 2 22 27 1988
- Meakin, P. “On growth and Form,” Stanley Ostrowsky Martinus-Nijhoff Publishers Boston 111 135 1986