This content is not included in your SAE MOBILUS subscription, or you are not logged in.
Air-Assisted Direct Firing for SI Combustion Engines
ISSN: 0148-7191, e-ISSN: 2688-3627
Published November 02, 2009 by SAE International in United States
Annotation ability available
The conception, design, simulation, and experimental evaluation of a novel SI combustion system will be presented in this paper. First, a new one-cylinder research engine was designed based on the combination of a port fuel injection engine with a centrally located direct minimal fuel-air mixture injection system. This combustion system is designed for low and mediate load conditions for moderate engine speeds, and aids the ignition process even when very high exhaust gas recirculation rates are present. It is also expected that the ignition stability under full load and under warm-up conditions will be improved significantly. The engine hardware fulfills the requirements of the MBtech “Integrated Combustion Development Process”, which allows operation of the research engine at all engine loads and speeds, while still supporting full optical access. A new additional injector is integrated on a four-valve cylinder head on a pent-roof combustion domain. This injector provides a minimal amount of fuel-air mixture under moderate pressure, in order to facilitate the ignition process in the presence of high EGR rates. Numerical simulation of the in-cylinder mixture formation process helps to improve the experimental setup for the combustion process as well as the injector layout design. For the proposed firing system, the thermodynamical results show promising improvements in fuel consumption and firing stability, while maintaining all of the advantages of the classic homogeneous SI combustion process.
CitationDittrich, P., Krämer, S., and Biemelt, A., "Air-Assisted Direct Firing for SI Combustion Engines," SAE Technical Paper 2009-01-2658, 2009, https://doi.org/10.4271/2009-01-2658.
- Waltner, A. Lückert, P. Schaupp, U. Rau, E. Kemmler, R. “Future Technology of the Spark-ignition Engine: Spray-guided Direct Injection with Piezo Injector“ th Vienna 2006
- Housten, R. Cathcart, G. Combustion and Emission Characteristics of Orbital's Combustion Process Applied to Multi-Cylinder Automotive Direct Injected 4-Stroke Engines SAE Technical Paper no. 980153 1998
- Krämer, S. Dittrich, P. Biemelt, A. Mlejnek, A. Reinhardt, N. “Optimierung des thermodynamischen Motorprozesses mittels integrierter Brennverfahrensentwicklung” ATZ/MTZ Extra 58922 June 2007
- Warnecke, V. Achleitner, E. Bäcker, H. “Development Status of the Siemens VDO Piezo Injection System for Spray-guided Combustion” th Vienna 2006
- Leonhard, R. Gerhardt, J. “Direct Injection – From Vision to Reality” th Vienna 2006
- Ducker, Ch. “Combustion Optimization of a Single Cylinder Engine with Combinated Injection” Thesis, University of Applied Sciences, Munich 2005