ISI BILIMI VE TEKNIGI DERGISI-JOURNAL OF THERMAL SCIENCE AND TECHNOLOGY, vol.41, no.1, pp.11-21, 2021 (SCI-Expanded)
The phase equilibria, engine performance and gas emissions of gasoline-ethanol-water blends with pyridine and isobutanol added for increased water tolerance, were investigated. It was observed that pyridine addition produced slightly higher ratios of ethanol and water in the stable fuel blend when compared to isobutanol, and the water ratio increased with the additive amount. Engine performances and combustion characteristics of the fuel blends were measured in a single cylinder, four-stroke, spark-ignition (SI) gasoline engine using different engine speeds and compared with the commercial gasoline. The best engine performance results were obtained from the HEP2 blend, consisting of 8.94% ethanol, 4.26% water and 4.21% pyridine. Using this fuel blend, engine torque increased by 8.3% at low speeds, engine effective power increased by %5 at high speeds while specific fuel consumption decreased by 14% at optimum engine speeds. Compared to the commercial gasoline blend, NOx, CO and HC emissions were found to be reduced by as much as %32, %17.9 and %45.9, respectively. Results showed that the fuel properties of pyridine and isobutanol added gasoline-ethanol-water blends were enhanced due to increased ethanol and water content and the HEP2 blend can be used in SI engines as an alternative to commercially available gasoline, with advantages of increased engine performance and reduced emission rates.