Size distribution, chemical composition and oxidation reactivity of particulate matter from gasoline direct injection (GDI) engine fueled with ethanol-gasoline fuel

Abstract Ethanol-gasoline blended fuels have been widely applied in markets recently, as ethanol reduces life-cycle greenhouse gas emissions and improves anti-knock performance. However, its effects on particulate matter (PM) emissions from gasoline direct injection (GDI) engine still need further investigation. In this study, the effects of ethanol-gasoline blended fuels on particle size distributions, number concentrations, chemical composition and soot oxidation activity of GDI engine were investigated. It was found that ethanol-gasoline blended fuels increased the particle number concentration in low-load operating conditions. In higher load conditions, the ethanol-gasoline was effective for reducing the particle number concentration, indicating that the chemical benefits of ethanol become dominant, which could reduce soot precursors such as large n-alkanes and aromatics in gasoline. The volatile organic mass fraction in ethanol-gasoline particulates matter was higher than that in gasoline particulate matter because ethanol reduced the amount of soot precursors during combustion and thereby reduced the elemental carbon proportions in PM. Ethanol addition also increased the proportion of small particles, which confirmed the effects of ethanol on organic composition. Ethanol-gasoline reduced the concentrations of most PAH species, except those with small aromatic rings, e.g., naphthalene. Soot from ethanol-gasoline has lower activation energy of oxidation than that from gasoline. The results in this study indicate that ethanol-gasoline has positive effects on PM emissions control, as the soot oxidation activity is improved and the particle number concentrations are reduced at moderate and high engine loads.

[1]  Seungmok Choi,et al.  Effects of Engine Operating Parameters on Morphology of Particulates from a Gasoline Direct Injection (GDI) Engine , 2013 .

[2]  Pavlos Aleiferis,et al.  Heat flux characteristics of spray wall impingement with ethanol, butanol, iso-octane, gasoline and E10 fuels , 2013 .

[3]  Ameya V. Joshi,et al.  Experimental Study of Carbon Black and Diesel Engine Soot Oxidation Kinetics Using Thermogravimetric Analysis , 2012 .

[4]  Michael C. Drake,et al.  Piston Fuel Films as a Source of Smoke and Hydrocarbon Emissions from a Wall-Controlled Spark-Ignited Direct-Injection Engine , 2003 .

[5]  L. Ntziachristos,et al.  Review of motor vehicle particulate emissions sampling and measurement: From smoke and filter mass to particle number , 2014 .

[6]  Anastassios M. Stamatelos,et al.  Thermogravimetric analysis of soot emitted by a modern diesel engine run on catalyst-doped fuel , 2003 .

[7]  Randy L. Vander Wal,et al.  Soot oxidation: dependence upon initial nanostructure , 2003 .

[8]  M. Maricq,et al.  The Impact of Ethanol Fuel Blends on PM Emissions from a Light-Duty GDI Vehicle , 2012 .

[9]  Su Han Park,et al.  Atomization and spray characteristics of bioethanol and bioethanol blended gasoline fuel injected through a direct injection gasoline injector , 2009 .

[10]  B. Stanmore,et al.  The oxidation of soot: a review of experiments, mechanisms and models , 2001 .

[11]  Jose Martin Herreros,et al.  University of Birmingham Impact of Fuel and Injection System on Particle Emissions from a GDI Engine , 2014 .

[12]  A. La Rocca,et al.  Part-load particulate matter from a GDI engine and the connection with combustion characteristics , 2014 .

[13]  J. Keskinen,et al.  Impact of vehicle development and fuel quality on exhaust nanoparticle emissions of traffic. , 2013, Environmental science & technology.

[14]  John A. Williams,et al.  High precision in-cylinder gas thermometry using Laser Induced Gratings: Quantitative measurement of evaporative cooling with gasoline/alcohol blends in a GDI optical engine , 2014 .

[15]  S. M. Sarathy,et al.  Alcohol combustion chemistry , 2014 .

[16]  D. Rothamer,et al.  Detailed Morphological Properties of Nanoparticles from Gasoline Direct Injection Engine Combustion of Ethanol Blends , 2013 .

[17]  C. Bergvall,et al.  Determination of highly carcinogenic dibenzopyrene isomers in particulate emissions from two diesel- and two gasoline-fuelled light-duty vehicles , 2009 .

[18]  Bianca Maria Vaglieco,et al.  Investigating the origin of nuclei particles in GDI engine exhausts , 2012 .

[19]  B. Stanmore,et al.  Experimental and theoretical study of oxygen diffusion within packed beds of carbon black , 2000 .

[20]  A. Majumdar,et al.  Opportunities and challenges for a sustainable energy future , 2012, Nature.

[21]  Jeff J. Jetter,et al.  Impact of gasoline composition on particulate matter emissions from a direct-injection gasoline engine: Applicability of the particulate matter index , 2014 .

[22]  Mark A. Villela,et al.  Evaluating the regulated emissions, air toxics, ultrafine particles, and black carbon from SI-PFI and SI-DI vehicles operating on different ethanol and iso-butanol blends , 2014 .

[23]  R. Stone,et al.  Measurement of Enthalpies of Vaporization of Isooctane and Ethanol Blends and Their Effects on PM Emissions from a GDI Engine , 2011 .

[24]  J. Herreros,et al.  Fuel Effect on Particulate Matter Composition and Soot Oxidation in a Direct-Injection Spark Ignition (DISI) Engine , 2014 .

[25]  John B. Heywood,et al.  Piston Fuel Film Observations in an Optical Access GDI Engine , 2001 .

[26]  Alberto Ayala,et al.  Determination of Suspended Exhaust PM Mass for Light-Duty Vehicles , 2014 .

[27]  Zhijin Zhang,et al.  Combustion and particle number emissions of a direct injection spark ignition engine operating on ethanol/gasoline and n-butanol/gasoline blends with exhaust gas recirculation , 2014 .

[28]  Steven H. Cadle,et al.  Effect of Ambient Temperature and E-10 Fuel on Primary Exhaust Particulate Matter Emissions from Light-Duty Vehicles , 1997 .

[29]  Peter Eastwood,et al.  Particulate Emissions from Vehicles , 2008 .

[30]  David L. Harrington,et al.  Automotive Spark-Ignited Direct-Injection Gasoline Engines , 2000 .

[31]  O. Armas,et al.  Impact of fuel formulation on the nanostructure and reactivity of diesel soot , 2012 .

[32]  J. Rodríguez-Fernández,et al.  Characterization of the Diesel Soot Oxidation Process through an Optimized Thermogravimetric Method , 2011 .

[33]  P. Gilot,et al.  Determination of kinetic data for soot oxidation. Modeling of competition between oxygen diffusion and reaction during thermogravimetric analysis , 1993 .

[34]  Keiya Nishida,et al.  Spray evaporation of ethanol–gasoline-like blend and combustion of ethanol–gasoline blend injected by hole-type nozzle for direct-injection spark ignition engines , 2014 .

[35]  Miguel Hernández-Campos,et al.  Experimental determination of some physical properties of gasoline, ethanol and ETBE blends , 2013 .

[36]  Matthew A. Ratcliff,et al.  Effects of Gasoline Direct Injection Engine Operating Parameters on Particle Number Emissions , 2012 .