Some Evidence for Chemical Effects on Octane Requirement Increase from Deposits in Spark Ignition Engines Shell Research and Technology Centre

Format:

Conference/Event

Author/Creator:

Price, R. J., author.

Conference Name:

International Spring Fuels & Lubricants Meeting & Exposition (1997-05-05 : Dearborn, Michigan, United States)

Language:

English

Physical Description:

1 online resource

Place of Publication:

Warrendale, PA SAE International 1997

Summary:

ABSTRACT.The octane requirement increase (ORI) observed in spark ignition engines essentially occurs due to the effect of deposits in the combustion chamber changing the heat transfer characteristics between the end-gas and the combustion chamber walls. In addition, the volume occupied by deposits produces a change in compression ratio inside each cylinder which also contributes to ORI. However, all the ORI observed in spark ignition engines cannot be explained by these physical effects alone and for some time the existence of a chemical mechanism of ORI has been postulated. Evidence is presented from a laboratory experiment which demonstrates that deposits are indeed able to influence the ignition delay times of fuel-air mixtures by providing a source of active species which help initiate autoignition. Such effects have also been observed in some engine experiments, thus confirming the existence of chemically based ORI

Notes:

Vendor supplied data

Publisher Number:

971668

Access Restriction:

Restricted for use by site license