Detailed Chemical Kinetic Modeling of Diesel Combustion with Oxygenated Fuels

The influence of oxygenated hydrocarbons as additives to diesel fuels on ignition, NOx emissions and soot production has been examined using a detailed chemical kinetic reaction mechanism. N-heptane was used as a representative diesel fuel, and methanol, ethanol, dimethyl ether and dimethoxymethane were used as oxygenated fuel additives. It was found that addition of oxygenated hydrocarbons reduced NOx levels and reduced the production of soot precursors. When the overall oxygen content in the fuel reached approximately 25% by mass, production of soot precursors fell effectively to zero, in agreement with experimental studies. The kinetic factors responsible for these observations are discussed.

[1]  William J. Pitz,et al.  A WIDE RANGE MODELING STUDY OF DIMETHYL ETHER OXIDATION , 1997 .

[2]  D. Montalvo,et al.  The Effect of Oxygenated Fuels on Emissions from a Modern Heavy-Duty Diesel Engine , 1993 .

[3]  B. I. Parsons,et al.  352. The oxidation of hydrocarbons and their derivatives. Part II. Structural effects in the ester series , 1956 .

[4]  T. J. Held,et al.  A comprehensive mechanism for methanol oxidation , 1998 .

[5]  Marco J. Castaldi,et al.  Aromatic and Polycyclic Aromatic Hydrocarbon Formation in a Laminar Premixed n-Butane Flame , 1998 .

[6]  J. Dec.  A Conceptual Model of DI Diesel Combustion Based on Laser-Sheet Imaging* , 1997 .

[7]  Noboru Miyamoto,et al.  Smokeless, Low NOx, High Thermal Efficiency, and Low Noise Diesel Combustion with Oxygenated Agents as Main Fuel , 1998 .

[8]  C. Westbrook,et al.  Comprehensive Mechanism for Methanol Oxidation , 1979 .

[9]  R. Blint,et al.  Concentration profiles in rich and sooting ethylene flames , 1988 .

[10]  William J. Pitz,et al.  The Autoignition Chemistry of Paraffinic Fuels and Pro-Knock and Anti-Knock Additives: A Detailed Chemical Kinetic Study , 1991 .

[11]  Frederick L. Dryer,et al.  The reaction kinetics of dimethyl ether. II: Low‐temperature oxidation in flow reactors , 2000 .

[12]  Marco J. Castaldi,et al.  Experimental and modeling investigation of aromatic and polycyclic aromatic hydrocarbon formation in a premixed ethylene flame , 1996 .

[13]  N. Marinov,et al.  A detailed chemical kinetic model for high temperature ethanol oxidation , 1999 .

[14]  James A. Miller,et al.  Kinetic and thermodynamic issues in the formation of aromatic compounds in flames of aliphatic fuels , 1992 .

[15]  Frederick L. Dryer,et al.  The reaction kinetics of dimethyl ether. I: High‐temperature pyrolysis and oxidation in flow reactors , 2000 .

[16]  C. Bamford,et al.  Comprehensive Chemical Kinetics , 1976 .

[17]  C. Westbrook,et al.  Prediction of laminar flame properties of methanol-air mixtures , 1980 .

[18]  M. Frenklach,et al.  Detailed modeling of soot particle nucleation and growth , 1991 .

[19]  J. Naber,et al.  Effects of Gas Density and Vaporization on Penetration and Dispersion of Diesel Sprays , 1996 .

[20]  C. Westbrook,et al.  A Comprehensive Modeling Study of n-Heptane Oxidation , 1998 .

[21]  William J. Pitz,et al.  DETAILED CHEMICAL KINETIC MECHANISMS FOR COMBUSTION OF OXYGENATED FUELS , 2000 .

[22]  C. M. Lund,et al.  HCT : a general computer program for calculating time-dependent phenomena involving one-demensional hydrodynamics, transport, and detailed chemical kinetics , 1978 .

[23]  Timothy J. Wallington,et al.  Experimental and Modeling Study of Premixed Atmospheric-Pressure Dimethyl Ether−Air Flames , 2000 .

[24]  C. Westbrook,et al.  Diesel combustion: an integrated view combining laser diagnostics, chemical kinetics, and empirical validation , 1999 .

[25]  M. Maricq,et al.  The Effect of Dimethoxy Methane Additive on Diesel Vehicle Particulate Emissions , 1998 .

[26]  James A. Miller.  Theory and modeling in combustion chemistry , 1996 .