Ethanol/Gasoline Droplet Heating and Evaporation: Effects of Fuel Blends and Ambient Conditions

Abstract

This paper focuses on the modelling of blended ethanol/gasoline fuel droplet heating and evaporation in conditions representative of internal combustion engines. The effects of ambient conditions (ambient pressure, ambient temperature and radiative temperature), and ethanol/gasoline fuel blend ratios on multi-component fuel droplet heating and evaporation are investigated using the analytical solutions to the heat transfer and species diffusion equations. The ambient pressures, gas and radiative temperatures, and ethanol/gasoline fuel ratios are considered in the ranges 3-30 bar, 400-650 K, 1000-2000 K, and 0% (pure gasoline)-100% (pure ethanol), respectively. Transient diffusion of 21 hydrocarbons, temperature gradient, and recirculation inside droplets are accounted for using the Discrete Component Model (DCM). The droplet lifetimes of all mixtures decrease at high ambient temperatures ( 400 K), under all ambient pressures (3-30 bar). The combination of ethanol and gasoline fuels has a noticeable impact on droplet heating and evaporation; for pure ethanol, the predicted droplet surface temperature is 33.9% lower, and lifetime 24.3% higher, than that for gasoline fuel under the same conditions. Finally, taking into account radiation increases the gasoline fuel droplet evaporation times by up to 28.6%, and those of ethanol fuel droplets by up to 21.8%, compared to the cases where radiation is ignored.

The Impact of Biodiesel Fuel on Ethanol/Diesel Blends

“…Soybean is a type of biodiesel fuel which refers to single alkyl esters of a long-chain fatty acid derived from vegetable oils. The physical properties of ethanol (anhydrous) are inferred from [35]. The physical properties for each component are calculated, with appropriate blending rules, to form the average properties of the blend.…”

“…The heating and evaporation of multi-component fuel droplets are essential processes for various combustion applications [29,30]. These processes have been widely investigated and different models have been proposed in [31,32], and validated in [33][34][35][36]. Some studies have been made to envisage the feasibility of blending biofuels with fossil fuels in terms of heating and evaporation [35,37].…”

“…These processes have been widely investigated and different models have been proposed in [31,32], and validated in [33][34][35][36]. Some studies have been made to envisage the feasibility of blending biofuels with fossil fuels in terms of heating and evaporation [35,37]. In this paper, the new key findings are the investigation into mixing different fractions of EBD blends with consideration of their droplet lifetimes and surface temperatures, viscosities, and CN.…”

Joint effect of advection, diffusion, and capillary attraction on the spatial structure of particle depositions from evaporating droplets

“…The processes of heat and mass transfer occurring in droplets and films are of interest in various applications such as fuel droplet evaporation and combustion in engines [1,2], interaction of droplets with surfaces of varying wettabilities in ink-jet printing [3], obtaining stable ultrathin film surfaces on the basis of polar liquids [4], removing nanoparticles from a solid surface [5], and many other applications.…”

Introductory Chapter: Biofuels - Challenges and Opportunities

“…To conclude, the use of biofuels is expected to contribute to the energy sustainability and reduction of global warming. For instance, many efforts have been made to replace gasoline and diesel fuels with ethanol/gasoline and biodiesel/diesel fuel blends, respectively [11][12][13][14][15][16]. These efforts have been driven mainly by the importance of reducing greenhouse emissions and fossil fuel costs [17][18][19].…”