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Optimized PFI+DI Operation For Minimizing DI Gasoline Engine Particulates
ISSN: 0148-7191, e-ISSN: 2688-3627
Published April 03, 2018 by SAE International in United States
This content contains downloadable datasetsAnnotation ability available
Direct Injection (DI) fueled gasoline engines provide higher efficiency than port fueled injected (PFI) engines. However, emission of small particulates is greatly increased when DI is used. Particulate mass emission is increased by more than a factor of 10 and particulate number is increased by a factor of 10-100 relative to PFI engines leading to health concerns and to implementation and consideration of new regulations.
Optimized combinations of PFI and DI can greatly reduce DI-generated particulate emissions without compromising efficiency and performance. A DI enhanced PFI mode of engine operation is employed where PFI is the dominant means in dual-injection fueling over a drive cycle, and the fuel fraction that is directly injected is reduced/minimized while still preventing knock at high loads. Further reduction can be obtained by optimal use of spark retard. The already low particulate emissions are further reduced by decreasing the percentage of DI fuel that results in particulate generation from wall wetting; this is accomplished by adjustment of injection timing, injection rate and pulse length.
We have developed a computational model of DI-generated particulates over the torque and speed map for gasoline engine operation with combined PFI and DI. The computational model includes models for knock suppression and for particulate generation from wall wetting. These models are calibrated using experimental data. We have used this computational approach to determine illustrative reductions in DI generated particulates for turbocharged gasoline engines various drive cycles. These reductions in DI-generated particulates for the US06 and UDDS cycles are greater than 20 and 50 times, respectively relative to the use of DI alone. An optimized PFI+DI system could be used in combination with a GPF for even further particulate reduction while also reducing GPF cost and the efficiency loss from GPF back pressure.
CitationBromberg, L. and Cohn, D., "Optimized PFI+DI Operation For Minimizing DI Gasoline Engine Particulates," SAE Technical Paper 2018-01-1415, 2018, https://doi.org/10.4271/2018-01-1415.
Data Sets - Support Documents
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- Zhao, F., Harrington, D.L., Lai, M.C. , “Automotive Gasoline Direct-injection Engines,” (SAE International, 2002), ISBN 10: 0768008824 ISBN 13: 9780768008821.
- Fraser, N., Blaxill, H., Lumsden, G., and Bassett, M. , “Challenges for Increased Efficiency Through Gasoline Engine Downsizing,” SAE Int. J. Eng. 2:991-1008, 2009, doi:10.4271/2009-01-1053.
- Mounting Evidence Indicts Fine-Particle Pollution,” Science 307(5717):1858-1861, 2005 PMID: 15790822.
- Whitaker, P., Kapus, P., Ogris, M., and Hollerer, P. , “Measures to Reduce Particulate Emissions from Gasoline DI Engines,” SAE paper 2011-01-1219, doi:10.4271/2011-01-1219.
- Zimmerman, N., Wang, J.M., Jeong, C.H. et al. , “Field Measurements of Gasoline Direct Injection Emission Factors Spatial and Seasonal Variability,” Environ. Sci. Technol. 50:2035-2043, 2016, doi:10.1021/acs.est.5b04444.
- Karjalainen, P., Pirjola, L., Heikkilä, J., Lähde, T. et al. , “Exhaust Particles of Modern Gasoline Vehicles: A Laboratory and an On-road Study,” Atmos. Environ. 97:262-270, 2014.
- Morey, B. , “Balancing GDI Fuel Economy and Emissions,” SAE Automotive Engineering, June 2015, p. 20
- United States Department of Transportation , “Final Regulatory Impact Analysis, Corporate Average Fuel Economy for MY 2012-MY 2016 Passenger Cars and Light Trucks,” (Washington, D.C., 2010).
- Chan, T.W., Meloche, E., Kubsh, J., Rosenblatt, D. et al. , “Evaluation of a Gasoline Particulate Filter to Reduce Particle Emissions from a Gasoline Direct Injection Vehicle,” SAE Int. J. Fuels Lubr. 5(3):1277-1290, 2012, doi:10.4271/2012-01-1727.
- Bidner, D, Cunninhan, R ., Russ, S ., Hilditch,J. and Rollinger, J. , Method and System For Engine Control, US Patent 8, 100, 107, 2012.
- Cohn, D.R. and Bromberg, L. , “Gasoline Particulate Reduction Using Optimized Port and Direct Injection,” US patent 9, 441, 570, 2016.
- Heiduk, T., Kuhn, M ., Stichlmeir, M and Unselt, F. , “The new 1.8L TFSI Engine from Audi part 2: Mixture Formation, Combustion Method and Turbocharging,” MTZ 72, (7-8), 58-64, 2011 doi: 10.1365/s38313-011-0078-1.
- F. Posada Sanchez, A. Bandivadekar and J. German , “Estimated Cost of Emission Reduction Technologies for Light-Duty Vehicles,” The International Council on Clean Transportation, www.theicct.org, March 2012.
- R.J. Minjares and F. Posada Sanchez , “Estimated Cost of Gasoline Particulate Filters,” The International Council on Clean Transportation, www.theicct.org, Sept. 2011, Paper number: 2011-8, 2011.
- Hedge, M., Weber, P., Gingrich, J., Alger, T. et al. , “Effect of EGR on Particle Emissions from a GDI Engine,” SAE Int. J. Engines 4(1):650-666, 2011, doi:10.4271/2011-01-0636.
- Ketterer, J. and Cheng, W. , “On the Nature of Particulate Emissions from DISI Engines at Cold-Fast-Idle,” SAE Int. J. Engines 7(2):986-994, 2014, di:10.4271/2014-01-1368.
- Ketterer, J. , “Soot Formation in Direct Injection Spark Ignition Engines Under Cold-Idle Operating Conditions,” Ph.D. thesis, Massachusetts Institute of Technology, PhD thesis, Available at http://hdl.handle.net/1721.1/85538, 2013