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The Optimization of a 26.2 cc, OHV, 4-Cycle Engine Aspiration System to Achieve 1999 CARB Emissions Standards
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This paper reviews the emissions reduction program that was pursued during the development of the small 26.2 cc, OHV, 4-cycle engine recently introduced by the Ryobi Group of Companies. This new engine's packaging and power density is designed to compete directly with pervasive, hand held, two-stroke power plants. The 4-cycle OHV design produces substantially less HC and CO emissions relative to the existing two stroke state-of-the-art hand held power plant. The challenge of minimizing NOx emission however is complicated by the practical limitations of low cost, diaphragm carburetor fuel metering systems. The levels of NOx emitted by the production engine are controlled by a careful manipulation of combustion chamber design, compression ratio, spark ignition timing, and internal and external exhaust gas recirculation. The results of experimental evaluations used to achieve a 1999 CARB standard capable design are discussed.
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Conley, J., Suchdev, L., Olsen, J., Kurihara, K. et al., "The Optimization of a 26.2 cc, OHV, 4-Cycle Engine Aspiration System to Achieve 1999 CARB Emissions Standards," SAE Technical Paper 961737, 1996, https://doi.org/10.4271/961737.Also In
Design, Modeling, and Emission Control for Small Two- and Four-Stroke Engines
Number: SP-1195; Published: 1996-08-01
Number: SP-1195; Published: 1996-08-01
References
- “California Exhaust Emission Standards and Test Procedures for the 1994 and Subsequent Model Year Utility and Lawn and Garden Equipment Engines” State of California Air Resources Board Hearing December 14 1990
- “Utility Engine Regulation Status Report” California Air Resources Board Staff Report Scheduled for consideration January 25 1996 Public Meeting
- Conley J. Olsen J. Kurihara K. Rickard G. “The New Ryobi 26.2 cc, OHV, 4-stroke Engine for Hand-Held Power Equipment Applications” SAE paper No. 961728 1996
- Conley J. Olsen J. Kurihara K. Rickard G. Hermann H. “The Development of a Durable, Cost Effective, Overhead Valve Train for Application to Small 4-Cycle Engines” SAE paper No. 961729 1996
- Sun X. Brereton G. Morrison K. Patterson D. “Small Engine Emissions” Off Highway Engineering December 1995 5 9
- Conley J. Asher D. “Team Management Practices and the Development of the AC 4-Cycle Engine” Proceedings of IMPRO 1996 The Juran Institute Wilton, Connecticut 1996
- Eccleston B. Hurn R. “Exhaust Emissions from Small, Utility Internal Combustion Engines” SAE Paper 720197 , SAE Transactions 81 1972
- Kollman R. Letz S. Meyer W. “Exhaust Emission characteristics of a Small, 2-Stroke Cycle Spark Ignition Engine” SAE Paper 730159 , SAE Transactions 82 1973
- Hare C. Springer K. Dliver W. Houtman W. “Small Engine Emissions and their Impact” SAE Paper 730858, SAE Transactions 82 1973
- White J. Carroll J. Hare C. Laurenco J. “Emissions Factors for Small Utility Engines” SAE Paper 910560 1991
- Daniel W. “Why Engine Variables Affect Exhaust Hydrocarbon Emissions” SAE Paper 700108 , SAE Transactions 79 1970
- Coates S. Lassanske G. “Measurement and Analysis of Gaseous Exhaust Emissions from Recreational and Small Commercial Marine Craft” SAE Paper 901597 1990
- Bowman C. “Kinetics of Pollutant Formation and Destruction in Combustion” Progress in Energy Combustion Science 1 33 45 1975
- Blumberg P. Kummer J. “Prediction of No x Formation in Spark-Ignition Engines--An Analysis of Methods of Control,” Combustion Science and Technology 4 73 96 1971
- Benson J. Stebar R. “Effects of Charge Dilution on Nitric Oxide Emission from a Single-Cylinder Engine” SAE paper 710008 , SAE Transactions 80 1971
- Komiyama K. Heywood J. “Predicting NO x Emissions and Effects of Exhaust Gas Recirculation in Spark-lgnition Engines” SAE Paper 930475, SAE Transactions 82 1973
- Sakai Y. Miyazaki H. Mukai K. “The Effect of Combustion Chamber Shape on Nitrogen Oxides” SAE Paper 730154 1973
- Brereton G. Morrison K. Christy H. Schwartz G. Patterson D. “Measured Emissions of Small Engines Under Steady and Transient Operations” SAE paper 941806 1994
- Sun X. Brereton G. Morrison K. Patterson D. “Emissions Analysis of Small Utility Engines” SAE Paper 952080 1995