Experimental investigation of butanol gasoline blends effect on the mass fraction burned in a spark ignition engine

Abstract

Abstract-The growing energy demand and the limitation of the fossil fuels force the transportation sector to seek for alternative energy sources. Butanol has emerged as one of the potential alternative energy solution especially for spark ignition engines. Experimental study on engine combustion characteristics particularly on mass fraction burned (MFB) of spark ignition engines fueled with secondary butyl alcohol (sec-butanol) gasoline blends was carried out. Engine was operated at engine speeds 3500 RPM with 50% of wide throttle open (WTO) for each blend (5%, 10% and 15% volume of sec-butanol) and neat gasoline. The in-cylinder pressure data were collected and the average cycle was integrate to obtain MFB profiles. Based on the MFB results at using sec-butanol gasoline blends is always taken higher value of degree of crank angle compared to gasoline fuels. However, throughout the analysis, by addition of 15% of volume in gasoline fuels reduced the 10 -90% early flame propagation, 10 -90% combustion duration and early position of degree of crank angle at 50% of MFB for 1.7%, 4.5% and 5.9% respectively with respect ot gasoline fuels.Index Terms-sec-butanol, gasoline fuels (G100), mass fraction burned (MFB) I. INTRODUCTION nergy security is an increasing critical issues due to the potential of fossil fuels dearth in near future [1]. As in consequences, the global energy consumption brings adverse effect toward environment and human health [2]. In 2013, the most consumed energy came from non-renewable energy which accounted for 82.67% among other energy sources in which crude oil, coal and natural gas by 30.92%, 28.95% and 22.81% respectively [3]. The petroleum fuels play a key factor especially in transportation area to meet the basic necessity of human needs. In order to combat the scarcity of petroleum fuels particularly in transportation areas a more efforts need to be done to find clean and sustainable alternative fuel [4].Gasoline engines are mostly the best choices for private and commercial used [5]. The use of oxygenated fuels in gasoline engines has a great potential of reducing the dependency of the petroleum fuels [6]. The main oxygenated alternative fuel used is alcohols mainly from ethanol for operation of gasoline-type vehicles [7]. However, for the past few years, the investigation of ethanol has received considerable critical attention with less attention paid to the butanol as a sustainable alternative fuel.Butanol is consider as an advanced alternative biofuel [8,9]. Butanol is a four carbon atom alcohol with chemical formula of C 4 H 10 O [10]. There are four types of butanol isomers categorized as n-butanol, secbutanol, tert-butanol and iso-butanol [11,12]. Each butanol is recognized based on their hydroxyl attached to one of the carbon atoms [13]. Each of these isomers have different physical and chemical properties [14]. As compared to ethanol, butanol is the most similar fuel properties to the gasoline fuel such as lower heating value, stoichiometric air-fuel ratio, research octane number a...