Publications:Estimation of Combustion Variability Using In-Cylinder Ionization Measurements
From ISLAB/CAISR
| Title | Estimation of Combustion Variability Using In-Cylinder Ionization Measurements |
|---|---|
| Author | Stefan Byttner and Thorsteinn Rögnvaldsson and Nicholas Wickström |
| Year | 2001 |
| PublicationType | Conference Paper |
| Journal | |
| HostPublication | |
| Conference | SAE International Fall Fuels & Lubricants Meeting & Exhibition, September 2001, San Antonio, TX, USA, Session: Experimental Investigation of SI Engines (Part A&B) |
| DOI | http://dx.doi.org/10.4271/2001-01-3485 |
| Diva url | http://hh.diva-portal.org/smash/record.jsf?searchId=1&pid=diva2:327068 |
| Abstract | This paper investigates the use of the ionization current to estimate the Coefficient of Variation for the Indicated Mean Effective Pressure, COV(IMEP), which is a common variable for combustion stability in a spark-ignited engine. Stable combustion in this definition implies that the variance of the produced work, measured over a number of consecutive combustion cycles, is small compared to the mean of the produced work. The COV(IMEP) is varied experimentally either by increasing EGR flow or by changing the air-fuel ratio, in both a laboratory setting (engine in dynamometer) and in an on-road setting. The experiments show a positive correlation between COV(Ion integral), the Coefficient of Variation for the integrated Ion Current, and COV(IMEP), when measured under low load on an engine in a dynamometer, but not under high load conditions. On-road experiments show a positive correlation, but only in the EGR and the lean burn case. An approach based on individual cycle classification for real-time estimation of combustion stability is discussed. |
