energies Review Spark Ignition Engine Combustion, Performance and Emission Products from Hydrous Ethanol and Its Blends with Gasoline Musaab O. El-Faroug 1,2,3, Fuwu Yan 1,2, Maji Luo 1,2,* and Richard Fiifi Turkson 1,2,4 1 Hubei Key Laboratory of Advanced Technology for Automotive Components, Wuhan University of Technology, Wuhan 430070, China;
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[email protected] (R.F.T.) 2 Hubei Collaborative Innovation Center for Automotive Components Technology, Wuhan University of Technology, Wuhan 430070, China 3 Mechanical Engineering Department, Faculty of Engineering, Elimam Elmahdi University, Kosti 11588, Sudan 4 Mechanical Engineering Department, Ho Polytechnic, P.O. Box HP 217, Ho 036, Ghana * Correspondence:
[email protected]; Tel.: +86-136-1863-8815 Academic Editor: Wenming Yang Received: 5 September 2016; Accepted: 15 November 2016; Published: 25 November 2016 Abstract: This paper reviews the serviceability of hydrous ethanol as a clean, cheap and green renewable substitute fuel for spark ignition engines and discusses the comparative chemical and physical properties of hydrous ethanol and gasoline fuels. The significant differences in the properties of hydrous ethanol and gasoline fuels are sufficient to create a significant change during the combustion phase of engine operation and consequently affect the performance of spark-ignition (SI) engines. The stability of ethanol-gasoline-water blends is also discussed. Furthermore, the effects of hydrous ethanol, and its blends with gasoline fuel on SI engine combustion characteristics, cycle-to-cycle variations, engine performance parameters, and emission characteristics have been highlighted. Higher water solubility in ethanol-gasoline blends may be obviously useful and suitable; nevertheless, the continuous ability of water to remain soluble in the blend is significantly affected by temperature.