Insights relating to octane rating and the underlying role of autoignition

The methods prescribed by the ASTM for Research and Motor octane number ratings are generally accepted as indicative of the anti-knock properties of gasoline when applied in spark ignition engines. However, it has been shown by the author that the manifestation of autoignition in the CFR engine that is used for octane rating differs significantly from that which is typically experienced in a modern production engine under knocking conditions (SAE paper 2005-01-2081). The present research examines the knock measurement system prescribed by the ASTM method and demonstrates how knock intensity is defined by the pressure rise associated with bulk autoignition heat release and that it is insensitive to the high frequency pressure fluctuations.

Grantor dc:publisher.institution

Department of Mechanical Engineering

Year dc:date.issued

2006

Author dc:creator

• Swarts, André

Advisor dc:contributor.advisor

• Yates, Andrew

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/11427/5465

OAI identifier oai:identifier

oai:open.uct.ac.za:11427/5465