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Sub-200 g/kWh BSFC on a Light Duty Gasoline Engine
ISSN: 0148-7191, e-ISSN: 2688-3627
Published April 5, 2016 by SAE International in United States
Annotation ability available
Increasingly stringent global fuel economy and carbon dioxide (CO2) legislation for light duty passenger cars has created an interest in unconventional operating modes. One such mode in spark ignition (SI) gasoline engines is lean combustion. While lean operation in SI engines has previously demonstrated the ability to reduce fuel consumption, the degree of enleanment capability of the system is limited by increasingly unstable combustion in the lean region, particularly for homogeneous lean approaches. MAHLE Jet Ignition® (MJI) is a pre-chamber-based combustion system that extends this lean limit beyond the capabilities of modern SI engines by increasing the ignition energy present in the system. This allows the engine to exploit the benefits of homogeneous ultra-lean (λ > ∼1.6) combustion, namely reduced fuel consumption and reduced emissions of nitrogen oxides (NOx).
Pre-chamber combustors such as that utilized in MJI have been studied extensively for decades. Pre-chamber-based jet ignition concepts have unique features such as flame quenching and ignition site targeting that enable further system optimization. In the present study, the engine performance improvement pathways of the system are explored through an examination of experimental results from single-cylinder and multi-cylinder engines incorporating the jet igniter. System operation is presented in detail. A minimum brake specific fuel consumption (BSFC) value of 200 g/kWh and a peak brake thermal efficiency (BTE) value of greater than 41% are analyzed and discussed, as are emissions data. Performance across the engine operating map and relevant system limitations are also presented. Accurate understanding of the potential performance of the jet ignition system throughout a typical engine operating envelope can lead to further system optimization, enable concept scalability, and inform system cost-benefit analyses.
CitationBunce, M. and Blaxill, H., "Sub-200 g/kWh BSFC on a Light Duty Gasoline Engine," SAE Technical Paper 2016-01-0709, 2016, https://doi.org/10.4271/2016-01-0709.
- Quader, A., "Lean Combustion and the Misfire Limit in Spark Ignition Engines," SAE Technical Paper 741055, 1974, doi:10.4271/741055.
- Husted, H., Piock, W., and Ramsay, G., "Fuel Efficiency Improvements from Lean, Stratified Combustion with a Solenoid Injector," SAE Int. J. Engines 2(1):1359-1366, 2009, doi:10.4271/2009-01-1485.
- Germane, G., Wood, C., and Hess, C., "Lean Combustion in Spark-Ignited Internal Combustion Engines - A Review," SAE Technical Paper 831694, 1983, doi:10.4271/831694.
- Heywood, J., Internal Combustion Engine Fundamentals, McGraw-Hill, 1988.
- Yamamoto, H., “Investigation on Relationship Between Thermal Efficiency and NOx Formation in Ultra-Lean Combustion,” SAE Journal Paper JSAE 9938083, 1999.
- Dober, G. G., Watson, H. C., “Quasi-Dimensional and CFD Modelling of Turbulent and Chemical Flame Enhancement in an Ultra Lean Burn S.I. Engine,” Modeling of SI Engines SP-1511, 2000.
- Ward, M., "High-Energy Spark-Flow Coupling in an IC Engine for Ultra-Lean and High EGR Mixtures," SAE Technical Paper 2001-01-0548, 2001, doi:10.4271/2001-01-0548.
- Qiao, A. and Wu, X., "Research on the New Ignition Control System of Lean- and Fast-Burn SI Engines," SAE Technical Paper 2008-01-1721, 2008, doi:10.4271/2008-01-1721.
- Ricardo, H., "Recent Research Work on the Internap-Combustion Engine," SAE Technical Paper 220001, 1922, doi:10.4271/220001.
- Gussak, L., Karpov, V., and Tikhonov, Y., "The Application of Lag-Process in Prechamber Engines," SAE Technical Paper 790692, 1979, doi:10.4271/790692.
- Robinet, C., Higelin, P., Moreau, B., Pajot, O. et al., "A New Firing Concept for Internal Combustion Engines: 'I'APIR'," SAE Technical Paper 1999-01-0621, 1999, doi:10.4271/1999-01-0621.
- Murase, E., Ono, S., Hanada, K., and Oppenheim, A., "Pulsed Combustion Jet Ignition in Lean Mixtures," SAE Technical Paper 942048, 1994, doi:10.4271/942048.
- Toulson, E., Schock, H., and Attard, W., "A Review of Pre-Chamber Initiated Jet Ignition Combustion Systems," SAE Technical Paper 2010-01-2263, 2010, doi:10.4271/2010-01-2263.
- Attard, W., Fraser, N., Parsons, P., and Toulson, E., "A Turbulent Jet Ignition Pre-Chamber Combustion System for Large Fuel Economy Improvements in a Modern Vehicle Powertrain," SAE Int. J. Engines 3(2):20-37, 2010, doi:10.4271/2010-01-1457.
- Attard, W., Kohn, J., Parsons, P., “Ignition Energy Development for a Spark Initiated Combustion System Capable of High Load, High Efficiency and Near Zero NOx Emissions,” SAE Journal Paper JSAE 20109088, 2010.
- Attard, W. and Blaxill, H., "A Gasoline Fueled Pre-Chamber Jet Ignition Combustion System at Unthrottled Conditions," SAE Int. J. Engines 5(2):315-329, 2012, doi:10.4271/2012-01-0386.
- Attard, W. and Blaxill, H., "A Lean Burn Gasoline Fueled Pre-Chamber Jet Ignition Combustion System Achieving High Efficiency and Low NOx at Part Load," SAE Technical Paper 2012-01-1146, 2012, doi:10.4271/2012-01-1146.
- Gomes, J., Valle, R., Pujatti, F., and Pereira, J., “Torch Ignition System Analysis in an Spark Ignition Engine,” SAE Technical Paper 2005-01-4149, 2005, doi:10.4271/2005-01-4149.
- Bunce, M., Blaxill, H., Kulatilaka, W., and Jiang, N., "The Effects of Turbulent Jet Characteristics on Engine Performance Using a Pre-Chamber Combustor," SAE Technical Paper 2014-01-1195, 2014, doi:10.4271/2014-01-1195.
- Bunce, M., Chinnathambi, P., Blaxill, H., “The Effects of Pre-Chamber-Initiated Lean Burn Combustion on Efficiency and Emissions,” Proceedings of the Institute of Mechanical Engineers 2015 Internal Combustion Engines conference, London, UK, 2015.
- Lean Gasoline Engine Emission Challenges, Parks, J., Edwards, K., Huff, S., Thomas, J., Norman, K., Prikhodko, V., Partridge, W., Choi, J., Chambon, P., Storey, J., Barone, T., CLEERS Focus Group Presentation, 3/31/2011.