An Experimental Study of Knock in a Natural Gas Fuelled Spark Ignition Engine Ecole Des Mines De Nantes, France

Format:

Conference/Event

Author/Creator:

Brecq, G., author.

Conference Name:

SAE International Fall Fuels & Lubricants Meeting & Exhibition (2001-09-24 : San Antonio, Texas, United States)

Spring Fuels & Lubricants Meeting & Exhibition (2002-05-06 : Reno, Nevada, United States)

Language:

English

Physical Description:

1 online resource

Place of Publication:

Warrendale, PA SAE International 2001

Summary:

Experiments were conducted on a single cylinder SI engine fuelled by natural gas. Equivalence ratios varying from 0.7 to 1.0 were used and the spark timing was changed from no knock to high knock conditions. Pressure crank angle data from 160 consecutive cycles was analysed. It was found that coefficient of variation of peak pressure (COVPP) and standard deviation of the angle of occurrence of peak pressure (SDAPP) can be used to set the engine for knock free operation. These parameters show a sudden rise from a minimum value that they attain near a spark timing where knock sets inches When the average knock intensity is low, there are two groups of cycles. The first comprises of non-knocking to slightly knocking ones. The other contains cycles with relatively high knock intensity. The sudden emergence of two groups is responsible for the observed trends of SDAPP. At high overall knock intensities the first group is absent. A threshold value could be fixed for the maximum rate of pressure rise to indicate the onset of knock. It was not possible to detect the onset of knock from cyclic variations in the IMEP or maximum rate of pressure rise

Notes:

Vendor supplied data

Publisher Number:

2001-01-3562

Access Restriction:

Restricted for use by site license