Effects of charge motion control during cold start of SI engines

An experimental study was conducted to investigate the effects of various intake charge motion control approaches on the cold start-up process of a port fuel injected SI engine. Engine experiments were performed to assess the effectiveness of enhanced charge motion on mixture preparation, combustion, and hydrocarbon (HC) emissions. Different charge motions were produced by three different shapes of charge motion control valves (CMCV), which block off 75% of the engine's intake ports. Cold-fluid steady state experiments were carried out with the CMCV open and closed. Increased charge motion with the CMCV closed was found to shorten the combustion duration, which caused the 50% mass fraction burned to occur up to 5⁰ CA earlier for the same spark timing. By the use of the CMCV, significant improvements in combustion stability (up to 1.5% reduction in COV) and fuel efficiency (up to 8% reduction in ISFC) were achieved with increased levels of spark timing retard due to enhanced air-fuel mixing and relatively faster burning. Engine start-up experiments were conducted with three different geometric charge motion control valves.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Mechanical Engineering.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2005

Author dc:creator

• Lee, Dongkun

Advisor dc:contributor.advisor

• John B. Heywood.

• Mechanical Engineering.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/33915

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/33915