This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Investigation of Combustion Robustness in Catalyst Heating Operation on a Spray Guided DISI Engine
Technical Paper
2009-01-1489
ISSN: 0148-7191, e-ISSN: 2688-3627
Annotation ability available
Sector:
Language:
English
Abstract
In catalyst heating operation for DISI (Direct Injection Spark Ignition) engines, split injection has been generally known to improve combustion stability which is critical for the trade-off between tailpipe emissions and vehicle idle NVH. This is also the case for a spray guided DISI engine employing multi-hole injectors and with both injector and spark plug centrally located in the chamber. There are some special challenges with regard to combustion robustness because of the close proximity between injector and spark plug. Investigations have been carried out through engine testing and CFD simulation to ensure combustion robustness.
For catalyst heating operation, the first injection occurs during induction, which forms a relatively well mixed but lean mixture in the cylinder before ignition, and the second injection occurs close to ignition, which produces a stratified fuel rich mixture in the central region of the combustion chamber. Combustion initialization is found to be sensitive to spark plug protrusion and orientation, injector orientation and 2nd injection timing relative to ignition. In some extreme conditions, misfire can occur. This is likely to be associated with the close proximity between the sprays and spark plug electrodes. However, the exact mechanisms are not so apparent. Various hypotheses have been postulated. Some of findings from the engine experiments and CFD simulations suggest that the sprays close to the spark plug electrodes may affect and interfere with the sparking process either through turbulence, bulk motion or liquid fuel mechanisms. Extensive engine testing has lead to optimized design and calibration that ensure robust combustion.
Recommended Content
Authors
Topic
Citation
Chen, X., Fu, H., Smith, S., and Sandford, M., "Investigation of Combustion Robustness in Catalyst Heating Operation on a Spray Guided DISI Engine," SAE Technical Paper 2009-01-1489, 2009, https://doi.org/10.4271/2009-01-1489.Also In
SI Combustion and Direct Injection SI Engine Technology, 2009
Number: SP-2241; Published: 2009-04-20
Number: SP-2241; Published: 2009-04-20
References
- Iwamoto Y. et al Development of Gasoline Direct Injection Engine SAE World Congress 970541 1997
- Harada Jun et al Development of Direct Injection Gasoline Engine SAE World Congress 970540 1997
- Hentschel W., et al Optical Diagnostics and CFD Simulations to Support the Combustion Process Development of the Volkswagen FSI Direct-Injection Gasoline Engine SAE World Congress 2001-01-3648 2001
- Schaupp Uwq et al Thermodynamic Potential of the Spray-Guided Combustion System for Gasoline Engines at Mercedes-Benz Aachener Kolloquium 2007
- Sadakane Shinji et al Development of a New V-6 High Performance Stoichiometric Gasoline Direct Injection Engine SAE World Congress 2005-01-1152 2005
- Ladenfeld Tilo et al Gasoline Direct Injection Engine – SULEV Emissions Concept SAE World Congress 2004-01-0041 2004
- Wurms Rainer et al Audi Turbo FSI Technology Aachener Kolloquium 2003
- Lecointe Betrand et al Downsizing a Gasoline Engine Using Turbocharging with Direct Injection SAE World Congress 2003-01-0542 2003
- Luttermann Christoph et al BMW High Precision Fuel Injection in Conjunction with Twin-Turbo Technology: a Combination of Maximum Dynamics and High Fuel Efficiency SAE World Congress 2007-01-1560 2007