Laminar burning velocity of gasoline and the gasoline surrogate components iso-octane, n-heptane and toluene

Abstract

-Removing the biomass limit is one of the great challenges to further enlarge the share of renewable ethanol as alternative for fossil fuels. One of the possible solutions for this constraint are the ternary GEM (Gasoline-Ethanol-Methanol) blends. The air-to-fuel ratio of these blends is hereby chosen at the value of an E85-blend (9.75 kg air/ kg fuel) while the ethanol is replaced by methanol/gasoline and therefore these blends are called 'isostoichiometric'. If the methanol is produced out of renewable sources, these blends can help extend the part of clean fuels on the market. The ternary blends show few differences in physical properties for the total range of possible blends and are considered as drop-in alternatives to the original E85-blend for a flex fuel engine. In this paper the performance and engine-out emissions of four of these GEM-blends were examined on a 4 cylinder 1.8 l PFI production engine. A single cylinder engine with high compression ratio was used for a preliminary study of the knock behavior of these blends. The measurement results are compared with those on neat gasoline, methanol and ethanol to demonstrate the potential of these ternary blends as a fossil fuel alternative. All the GEM fuels which were tested gave very similar results to E85 and can therefore indeed be used as 'drop-in' fuels for flex-fuel vehicles.

Laminar Flame Characteristics of C1–C5 Primary Alcohol-Isooctane Blends at Elevated Temperature

“…Figure 2a,b gives the laminar flame speeds of pure ethanol and isooctane flames at 0.1 MPa, respectively. It is seen the present data are in good agreement with the data from literatures [10,[46][47][48][49][50]. Figure 2c gives the laminar flame speeds of ethanol-isooctane blend-air mixtures versus volume fraction of ethanol at 0.1 MPa.…”

“…Heavy alcohols have high energy contents and blend well with traditional fuels. Isooctane is identified as the representative branched paraffin and, hence an important constituent in the surrogates of traditional fuels [9][10][11], therefore, investigating alcohol-isooctane blends can provide valuable information for understanding the potential of alcohols as alternative fuels.…”

Laminar flame speed of lignocellulosic biomass-derived oxygenates and blends of gasoline/oxygenates

“…In traditional petroleum-based gasoline fuels, the oxygenated components are quite limited which can be neglected. The same consideration with previously proposed surrogate gasoline in literature [24][25][26][27][28][29], in the present work the surrogate gasoline composition only consisted of hydrocarbon fuels. Fractions of alkanes and aromatics compounds (i.e.…”

“…However, commercial gasoline consists of hundreds or thousands chemical components and its composition varies among the different sites of production, a quantitative understanding of the role of the species composition on the laminar flame speed property is still complex to perform for the wide range of operating conditions similar with those encountered in real engines generally investigated. Therefore, utilization of component identified surrogate gasoline that can successfully reproduce the properties of commercial gasoline fuel is necessary [24][25][26][27][28][29]. In the present work, a surrogate gasoline to emulate the commercial gasoline consists of five pure components: hexane, 2, 3-dimethylbut-2-ene, cyclohexane, iso-octane and toluene is proposed.…”

“…In the present work, a surrogate gasoline to emulate the commercial gasoline consists of five pure components: hexane, 2, 3-dimethylbut-2-ene, cyclohexane, iso-octane and toluene is proposed. Hereby, as the petroleum based gasoline contains quite limited oxygenated compounds which can be neglected the surrogate gasoline proposed in the present work only consisted of hydrocarbon fuels [14][15][16][17][18][19][20][21][22][23][24][25]. The second purpose of the present study is therefore to experimentally elucidate if this five-component surrogate gasoline fuel is capable to reproduce the laminar flame speed property of commercial gasoline.…”