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The Evaluation of a Computer Controlled Air Pump for Improved Automobile Emissions
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Abstract
Proof-of-concept testing was performed to determine the effectiveness of a computer controlled air pump (CCAP) in reducing the unburned hydrocarbons (UHC) and carbon monoxide (CO) emitted from automobile engines. For the initial phase of testing, a prototype CCAP was designed and evaluated on a dynamometer test-stand at the University of Tennessee. This CCAP maintained the engine's exhaust at a stoichiometric air/fuel ratio by utilizing a second oxygen sensor mounted downstream from the catalyst. In this way, the catalyst's conversion efficiency for CO and UHC was always high, even if the engine was running rich. Results of this steady-state testing indicated that the CCAP was able to reduce UHC and CO emissions without a corresponding increase in oxide of nitrogen (NOx) emissions. Additionally, catalyst temperatures did not increase dramatically.
For the second phase of testing, the CCAP was installed on a vehicle and four sets of emission tests were performed at the Environmental Protection Agency's Environmental Research Center Annex in Research Triangle Park, NC. As a result of testing, it was determined that the CCAP has merit as a system to decrease CO and UHC emissions during acceleration and power enrichment. However, the CCAP must be activated after the catalyst has lit-off (or it can delay catalyst light-off and result in poor emissions). NOx emissions remained essentially unchanged and catalyst temperatures did not increase by more than 110 °C. Recomendations for further study are made.
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Citation
Snook, L. and Hodgson, J., "The Evaluation of a Computer Controlled Air Pump for Improved Automobile Emissions," SAE Technical Paper 940977, 1994, https://doi.org/10.4271/940977.Also In
References
- Black, Frank M. “Control of Motor Vehicle Emissions - The U.S. Experience” Critical Reviews in Environmental Control 21 5 6 373 410 1991
- Heywood, John B. Internal Combustion Engine Fundamentals McGraw Hill 1988
- National Research Council Rethinking the Ozone Problem in Urban and Regional Air Pollution National Academy Press 1992
- Probst, Charles O. Bosch Fuel Injection and Engine Management Robert Bently, Inc., Publishers 1989
- Hodgson, J.W. Adams, R.K. The Student Team “The University of Tennessee Methanol Corsica - Engineering for Low Emissions, High Performance” SAE Paper No. 902100 Society of Automotive Engineers 1990
- Cooper, Barry “The Future of Catalytic Systems” Automotive Engineering 100 4 Society of Automotive Engineers April 1992
- Bozek, John W. Evans, Richard Tyree, Clifford D. Zerafa, Kenneth L. “Operating Characteristics of Zirconia Galvanic Cells (Lambda Sensors) in Automotive Closed-Loop Emission Control Systems” SAE Paper No. 920289 Society of Automotive Engineers 1992
- Gabele, Peter A. Knapp, Kenneth T. Snow, Richard F. Siudak, Paula D. Perry, Ned K. McArvver, Alexander Q, “A Characterization of Emissions from an Early Model FFV” Air & Waste Management Association 1991
- Federal Register April 11 1989
- Kelly, Nelson A. Grobliki, Peter J. “Real-World Emissions from a Modern Production Vehicle Driven in Los Angeles” Air & Waste 43 October 1993