Abstract
This work explores the dependence of fuel distillation and flame speed on low-speed pre-ignition (LSPI). Findings are based on cylinder pressure analysis, as well as the number count, clustering, intensity, duration, and onset crank angle of LSPI events. Four fuels were used, with three of the fuels being blends with gasoline, and the fourth being neat gasoline. The blended fuels consisted of single molecules of different molecular types: a ketone (cyclopentanone), an alcohol (2-methyl-1-butanol), and an aromatic (ethylbenzene). All three pure molecules have RON values within ±2 and boiling points within ±5 °C. These fuels were blended with gasoline to a 25% mass fraction and were used to run the engine at identical LSPI prone operating conditions. The findings highlight that fuels with similar boiling properties and octane numbers can exhibit similar LSPI number counts, but with vastly different LSPI magnitudes and intensities. Moreover, the results highlight fundamental fuel properties such as flame speed are critical to characterizing the LSPI propensity and behavior of the fuel.
Original language | English |
---|---|
Pages (from-to) | 474-482 |
Number of pages | 9 |
Journal | Fuel |
Volume | 230 |
DOIs | |
State | Published - Oct 15 2018 |
Funding
This research was conducted as part of the Co-Optimization of Fuels & Engines (Co-Optima) project sponsored by the U.S. Department of Energy ( DOE ) Office of Energy Efficiency and Renewable Energy ( EERE ), Bioenergy Technologies and Vehicle Technologies Offices. Co-Optima is a collaborative project of multiple National Laboratories initiated to simultaneously accelerate the introduction of affordable, scalable, and sustainable biofuels and high-efficiency, low-emission vehicle engines. A special thanks is due to program managers Kevin Stork, Gurpreet Singh, Leo Breton, and Mike Weismiller.
Keywords
- Fuel effects
- LSPI
- Preignition
- Spark ignition
- Superknock