Experimental investigation of performance and emission improvement by altering ignition timing with use of E10 ethanol blend in SI engine

Abstract

In this study, the best ignition timing for an SI engine with the use of E10 ethanol blend was experimentally investigated. Ignition timing was retarded successively by 2° up to 6° at most (denoted as −2, −4 and −6 respectively) and then advanced by 2° successively up to 6° (denoted as +2, +4 and +6 respectively) with respect to the advance values realised with gasoline (termed as ‘original advance values’) at full load operation. It was generally observed that overall efficiency increases with advanced ignitions. The best performance and emissions were obtained with +4. This increase amounts to 6% for 4° advanced ignition at 3000 rev min⁻¹. Advanced ignition timing resulted with increase in NO_x emissions, while CO and CO₂ remained relatively unaffected. Increasing retard in ignition timing caused poorer combustion and hence more fuel consumption but less hydrocarbon emissions.

Keywords:

• E10
• Gasoline
• SI engine
• Emission
• Spark timing

This work was supported by The Research Fund of the Uludag University (Project no. UAP(M)-2010/17) and the authors are grateful for infrastructure support from TUBITAK (Project no. 107 M405).