This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Injection Timing and Bowl Configuration Effects on In-Cylinder Particle Mass
Annotation ability available
Sector:
Language:
English
Abstract
The formation of particles in the combustion chamber of a direct injection diesel engine has been studied with the use of the Total Cylinder Sampling Method. With this method, nearly the entire contents of the cylinder of an operating diesel engine can be quickly removed at various times during the combustion process. The particle mass and size distributions present in the sample can then be analyzed. If quenching of the combustion process is quick and complete, the resulting samples are representative of the particle mass and size distributions present in the cylinder near the time sampling begins. This paper discusses the effect of injection timing and piston bowl shape on the particle formation and oxidation. Example size distribution measurements are also shown.
The particle concentrations in the cylinder were measured for three different injection timings with the standard piston installed in the engine. Measurements were also made at the base timing with an alternate piston containing a more reentrant bowl. The particle concentrations rise quickly after the start of combustion, peaking approximately 12 degrees later. Peak levels are 4 to 9 times the exhaust levels. Oxidation during the expansion stroke reduces the particle mass concentration to the exhaust levels. Injection timing had a significant effect on the profiles measured. While peak concentrations were similar, the oxidation was less effective in reducing the mass as the timing was retarded. This resulted in the advanced timing condition having the lowest exhaust concentrations of the standard piston conditions. At other conditions, oxidation was less effective in reducing the mass, resulting in higher exhaust concentrations.
The reentrant bowl configuration results showed peak cylinder concentrations similar to the standard piston, but the profile was broader than for the standard bowl. Oxidation continued further into the expansion stroke, leading to exhaust concentrations only half as high as for the standard bowl configuration. Measurements of both the agglomerate and primary particle size distributions can also be made on samples collected during these experiments. This paper presents an example of these measurements. The size of the agglomerates appears to approach that of the exhaust by approximately 20 CAD after the start of combustion. The size of the primary particles increases during early combustion but is reduced later in the cycle due to oxidation. The total reduction in the primary particle size is not enough to account for the reduction of total particle mass, indicating that some particles are being completely oxidized while others are oxidized only partially.
Recommended Content
Authors
Topic
Citation
Pipho, M., Kittelson, D., Luo, L., and Zarling, D., "Injection Timing and Bowl Configuration Effects on In-Cylinder Particle Mass," SAE Technical Paper 921646, 1992, https://doi.org/10.4271/921646.Also In
References
- Brehob, D. D. Kittelson D. B. “A Review of CI In-Cylinder Diagnostics for the Investigation of Soot Loading, Composition, and Temperature,” SAE Paper No. 880815 1988
- Hedding, G. H. Kittelson D. B. Scherrer H. Lui X. Dolan D. F. “Total Cylinder Sampling from a Diesel Engine,” SAE Paper No. 810257 1981
- Lui, X. Kittelson D. B. “Total Cylinder Sampling form a Diesel Engine (Part II),” SAE Paper No. 820360 1982
- Du, C. J. Kittelson D. B. “Total Cylinder Sampling from a Diesel Engine: Part III - Particle Measurements,” SAE Paper No. 830243 1983
- Pipho, M. J. Ambs J. L. Kittelson D. B. “In-Cylinder Measurements of Particulate Formation in an Indirect Injection Diesel Engine,” SAE Paper No. 860024 1986
- Kittelson, D. B. Pipho M. J. Ambs J. L. Luo L. “In-Cylinder Measurements of Soot Production in a Direct-Injection Diesel Engine,” SAE Paper No. 861569 1986
- Pipho, Michael J. Total Cylinder Sampling From a Diesel Engine University of Minnesota June 1990
- Takeuchi, K. Kubota K. Konagai M. Watanabe M. Kihara R. “The New Isuzu 2.5 Liter and 2.8 Liter 4-Cylinder Direct Injection Diesel Engine,” SAE Paper No. 850261 1985
- Mueller, R. S. Vitvlugt M. W. “Valve Selector Hardware,” SAE Paper No. 780146 1978
- Hedding, G. H. Kittelson D. B. Scherrer H. Lui X. Dolan D. F. “Total Cylinder Sampling from a Diesel Engine,” SAE Paper No. 810257 1981
- Du, C. J. Kittelson D. B. “Total Cylinder Sampling from a Diesel Engine: Part III - Particle Measurements,” SAE Paper No. 830243 1983
- Pipho, M. J. Ambs J. L. Kittelson D. B. “In-Cylinder Measurements of Particulate Formation in an Indirect Injection Diesel Engine,” SAE Paper No. 860024 1986
- Kittelson, D. B. Pipho M. J. Ambs J. L. Siegla D. C. “Particle Concentrations in a Diesel Cylinder: Comparison of Theory and Experiment,” SAE Paper No. 861569 1986
- Luo, Lang In-Cylinder Particulate Size Distributions In a Direct Injection Diesel Engine University of Minnesota 1991
- Luo, Lang In-Cylinder Particulate Size Distribution Measurements in a Direct Injection Diesel Engine University of Minnesota 1991
- Fennimore, C. P. Jones G. W. “Oxidation of Soot by Hydroxyl Radicals,” J. of Physical Chemistry 71 3 593 597
- Hiroyosu, H. Yoshimatsu A. Arai M. “Mathematical Model for Predicting the Rate of Heat Release and Exhaust Emissions in IDI Diesel Engines,” Inst. of Mech. Engineers 1982
- Pipho, Michael J. Total Cylinder Sampling From a Diesel Engine University of Minnesota 1991