Examination of nanoparticles from gasoline direct-injection (GDI) engines using transmission electron microscopy (TEM)
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Gasoline direct-injection (GDI) engines have been reported to produce significantly more particulate matter (PM) mass and particulate number (PN) emissions than do port-fuel-injection (PFI) spark ignition engines. Because smallsized particles are of great concern in terms of their regulation, transmission electron microscopy (TEM) was used to evaluate the sizes of primary and aggregate particles that were thermophoretically collected from three different GDI engines under various engine operating conditions. A low load and retarded fuel injection generally reduced the particle size. Consequently, when the fuel injection timing was delayed at low loads, primary and aggregate particles became extremely small. In particular, a number of nanoparticles were sub-23-nm particles. Careful high-resolution TEM (HRTEM) analyses provided the first evidence that these nanoparticles are solid carbon particles with clear fringe patterns and young soot (and/or highly condensed semi-volatiles) with amorphous carbon patterns. Therefore, this result suggests that the current cut-off size at 23 nm for PN regulation in Euro 6 must be further reduced to include sub-23-nm carbon nanoparticles.
Key WordsSub-23-nm particles Solid carbon nanoparticles GDI engines TEM analysis Morphology PN regulation
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- Andersson, J., Giechaskiel, B., Munoz-Bueno, R., Sandbach, E. and Dilara, P. (2007). Particle Measurement Programme (PMP) Light-duty Inter-laboratory Correlation Exercise (ILCE-LD) Final Report. Institute for Environment and Sustainability. EUR 22775 EN.Google Scholar
- Andersson, J., Mamakos, A., Giechaskiel, B., Carriero, M. and Martini, G. (2010). Particle Measurement Programme (PMP) Heavy-duty Inter-laboratory Correlation Exercise (ILCE-HD) Final Report. Final Report. Joint Research Center, Ispra (VA). EUR 24561 EN.Google Scholar
- CARB (2010). Preliminary Discussion Paper — Proposed Amendments to California’s Low-emission Vehicle Regulations — Particulate Matter Mass, Ultrafine Solid Particle Number, and Black Carbon Emissions. California Air Resources Board, Sacramento, CA. 11 May.Google Scholar
- Giechaskiel, B., Chirico, R., DeCarlo, P. F., Clairotte, M., Adam, T., Martini, G., Heringa, M. F., Richter, R., Prevot, A. S. H., Baltensperger, U. and Astorga, C. (2010). Evaluation of the particle measurement programme (PMP) protocol to remove the vehicles’ exhaust aerosol volatile phase. Science of the Total Environment 408,21, 5106–5116.CrossRefGoogle Scholar
- Jung, H., Zheng, Z., Johnson, K. C., Liu, Z., Durbin, T. D., Kittelson, D. B., Hu, S. and Huai, T. (2011). Measurement of diesel solid nanoparticle emissions using a catalytic stripper for comparison with Europe’s PMP protocol. Directions in Engine-Efficiency and Emissions Research (DEER).Google Scholar
- Lee, K., Seong, H., Church, W. and McConnell, S. (2012). Examination of particulate emissions from alcohol blended fuel combustion in a GDI engine. The 8 th Int. Symp. Diagnostics and Modeling of Combustion in Internal Combustion Engines (COMODIA). Fukuoka, Japan.Google Scholar