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Investigation of Post Oxidation and Its Dependency on Engine Combustion and Exhaust Manifold Design
Technical Paper
2002-01-0744
ISSN: 0148-7191, e-ISSN: 2688-3627
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English
Abstract
In response to ever more stringent emission limits (EURO IV, SULEV), engine developers are increasingly turning their attention to engine start-up and warm-up phases. Since in this phase the catalytic converter has not yet reached its operating temperature, problems occur especially with regard to hydrocarbon emissions (HC) which are emitted untreated. Secondary air injection represents one option for heating up the catalytic converter more quickly. The engine is operated during the heating up cycle with retarded ignition angles and a rich mixture. Ambient air (secondary air) is injected close to the exhaust valve seat. During the spontaneously occurring post oxidation phase, the reactive exhaust components ignite and heat up the catalytic converter while simultaneously reducing HC.
The various processes which affect the post oxidation, are not well known up to now. In order to achieve concrete improvements, detailed knowledge of its influences are necessary. This paper will give an overview of these complex relationships. For the investigations fast response measuring techniques are installed to record the reaction of the secondary air and exhaust gas so the local formation of the reaction zone can be detected. A high-speed camera is used to display the reaction fields on an exhaust manifold made of quartz glass. The internal dimensions of this glass manifold correspond to the series production manifold. A comparison with the appropriate image sequences from CFD calculations aids in understanding and interpreting the processes. We can see that not only the quality of the mixture formation and combustion in the combustion chamber but most especially the distribution of flow, temperature and concentration of air and exhaust gas in the exhaust manifold are decisive for optimum post oxidation.
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Authors
Topic
Citation
Koehlen, C., Holder, E., and Vent, G., "Investigation of Post Oxidation and Its Dependency on Engine Combustion and Exhaust Manifold Design," SAE Technical Paper 2002-01-0744, 2002, https://doi.org/10.4271/2002-01-0744.Also In
References
- Kollmann K. Abthoff J. Zahn W. “Secondary Air Injection with a New Developed Electrical Blower for Reduced Exhaust Emissions” SAE 940472
- Niefer H. Weining H. Bargende M. Waltner A. “Verbrennung, Ladungswechsel und Abgasreinigung der neuen Mercedes-Benz V-Motoren mit Dreiventiltechnik und Doppelzündung” MTZ 58 1997
- Umehara K. Tateishi T. Nishimura H. Mismi M. “HC-Reduction System for Cold Start and Warm-Up Phases - Improvement of Catalyst Warm-Up by Retarded Ignition” JSAE Review 18 1997 57 82
- Russ S. Thiel M. Lavoie G. “SI Engine Operation with Retarded Ignition: Part 2-HC Emissions and Oxidation” SAE 1999-01-3507
- Meyer R. Heywood J. “Liquid Fuel Transport Mechanisms into the Cylinder of a Firing Port-Injected SI Engine During Start Up” SAE 970865
- Takeda K. Yaegashi T. Sekiguchi K. Saito K. Imatake N. “Mixture Preparation and HC Emissions of a 4-Valve Engine with Port Fuel Injection During Cold Start and Warm-up” SAE 950074
- Crane M. Thring R. Podnar D. Dodge L. “Reduced Cold-Start Emissions Using Rapid Exhaust Port Oxidation (REPO) in a Spark-Ignition Engine” SAE 970264
- Finaly I. Boam D. Bingham J. Clark T. “Fast Response FID Measurement of Unburned Hydrocarbons in the Exhaust Port of a Firing Gasoline Engine” SAE 902165
- Henein N. Tagomori M. Yassine M. Asmus T. “Cycle-by-Cycle Analysis of HC Emissions during Cold Start of Gasoline Engines” SAE 952402
- Ma T. Collings N. Hands T. “Reduction of Exhaust Emissions during Engine Cold Start by means of an Afterburner Operating in the Hydrogen Ignitable Regime” 4 th International EAEC Conference on Vehicle and Traffic Systems Technology Strasbourg 2 365 372 1993
- Kessler M. “Ionenstromsensorik im Dieselmotor” University Karlsruhe 2002
- Gerhardt P. Homann K. Löffler S. Wolf H. “Large Ionic Species in Sooting Acetylene and Benzene Flames” 20 th Symposium (International) on Combustion 1121 1128 1988
- Seifert H. “Twenty Years successful Development of Gas Exchange Program PROMO” Motortechnische Zeitschrift 478 488 1996
- Nebel M. “Transient simulation of the flow in an exhaust manifold” Konferenz-Einzelbericht: Berechnung u. Simulation im Fahrzeugbau VDI-Berichte 1283 401 409 1996