This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Numerical Study on Swirl-Type High-Dilution Stratified EGR Combustion System
Technical Paper
2000-01-1949
ISSN: 0148-7191, e-ISSN: 2688-3627
Annotation ability available
Sector:
Language:
English
Abstract
High-dilution stratified EGR combustion system operating at stoichiometric air-fuel ratio (A/F) could offer significant fuel economy saving comparable to the lean burn or stratified charge direct injection SI engines, while still complies with stringent emission standards by using the conventional three-way catalytic converter. The most critical challenge is to keep substantial separation between EGR gas and air-fuel mixture, or to minimize the mixing between these two zones to an acceptable level for stable and complete combustion. Swirl-type stratified EGR and air-fuel flow structure is considered desirable for this purpose, because the circular engine cylinder tends to preserve the swirl motion and the axial piston movement has minimal effect on the flow structure swirling about the same axis. In this study, KIVA3V was used to simulate mixing and combustion processes in a typical pent-roof gasoline engine cylinder during compression and expansion strokes. Overall EGR rate, swirl ratios and directions of both air and EGR gas, and EGR amount mixed into the stoichiometric air-fuel mixture, were varied to understand critical issues in the processes and to find out the limitations. The effects of differences in velocity, temperature and density between the air and the EGR gas, turbulence intensity, and centrifugal force, on the mixing between the two zones were discussed. The simulation results demonstrated the expected benefits and feasibility of this high-dilution stratified EGR combustion system concept.
Authors
Topic
Citation
Xu, M., Chen, G., Daniels, C., and Dong, M., "Numerical Study on Swirl-Type High-Dilution Stratified EGR Combustion System," SAE Technical Paper 2000-01-1949, 2000, https://doi.org/10.4271/2000-01-1949.Also In
References
- Han S. Cheng W. K. “Design and Demonstration of a Spark Ignition Engine Operating in a Stratified-EGR Mode,” SAE Paper 980122
- Jackson N. S. Stokes J. Lake T. H. Sapsford S. M. Heikal M. Denbratt I. “Understanding the CCVS Stratified EGR Combustion System,” SAE Paper 960837
- Ditiu M. “Triple Stratification in a Spark Ignition Engine: The Effect on the Emission at Unthrottled Light Load,” SAE Paper 1999-01-0575
- Groves W. N. Bjorkhaug M. “Stratified Exhaust Gas Recirculation in a S. I. Engine,” SAE Paper 860318
- Martelli R. L. Warren C. Stockhausen W. F. “Stratified Exhaust Residual Engine,”
- Amsden A. A. “KIVA-3V: A Block-Structured KIVA Program for Engines with Vertical or Canted Valves,” Los Alamos National Laboratory Report LA-13313-MS
- Bird R. B. Steward W. E. Lightfoot E. N. “Transport Phenomena,” John Wiley & Sons
- Amsden A. A. O'Rourke P. J. Butler T. D. “KIVA-II: A Computer Program for Chemically Reactive Flows with Sprays,” Los Alamos National Laboratory Report LA-11560-MS
- Amsden A. A. “KIVA-3: A KIVA Program with Block-Structure Mesh for Complex Geometries,” Los Alamos National Laboratory Report LA-12503-MS