Investigation on combustion and emissions of DME/gasoline mixtures in a spark-ignition engine

Dimethyl ether (DME) has a lot of good properties and is thought to be one of the best alternative fuels for IC engines in the future. In order to improve the efficiency, combustion stability and emissions performance of a spark-ignited (SI) gasoline engine at stoichiometric condition, an experimental study aiming at improving engine performance through DME addition was carried out on a four-cylinder SI engine. The engine was modified to be fueled with the mixture of gasoline and DME which were injected into the engine intake ports simultaneously. A hybrid electronic control unit (HECU) was dedicatedly developed to control the injection timings and durations of gasoline and DME. The spark timing was adjusted to reach the maximum brake torque (MBT) without knocking. Various DME fractions were selected to investigate the effect of DME addition on engine performance, thermal efficiency, combustion characteristics, cyclic variation and emissions under stoichiometric conditions. The experimental results showed that thermal efficiency, NOx and HC emissions are improved with the increase of DME addition level. The combustion performance was improved when DME addition fraction was less than 10%. CO emission first decreased and then increased with the increase of DME enrichment level at stoichiometric condition.

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

[2]  Toshio Shudo,et al.  Hydrogen as an ignition-controlling agent for HCCI combustion engine by suppressing the low-temperature oxidation , 2007 .

[3]  Alex M. K. P. Taylor,et al.  Science review of internal combustion engines , 2008 .

[4]  Robert W. Dibble,et al.  AUTOIGNITION OF DIMETHYL ETHER AND DIMETHOXY METHANE SPRAYS AT HIGH PRESSURES , 1997 .

[5]  Yong Li,et al.  Effects of hydrogen addition on cycle-by-cycle variations in a lean burn natural gas spark-ignition engine , 2008 .

[6]  Derek Dunn-Rankin,et al.  Lean Combustion Technology and Control , 2011 .

[7]  R. Borup,et al.  Dimethyl ether (DME) as an alternative fuel , 2006 .

[8]  Seungmook Oh,et al.  Performance and emission characteristics of an SI engine operated with DME blended LPG fuel , 2009 .

[9]  Choongsik Bae,et al.  Gasoline−Di-methyl Ether Homogeneous Charge Compression Ignition Engine , 2007 .

[10]  Choongsik Bae,et al.  Dimethyl ether (DME) spray characteristics in a common-rail fuel injection system , 2003 .

[11]  Zunqing Zheng,et al.  Study on the controlling strategies of homogeneous charge compression ignition combustion with fuel of dimethyl ether and methanol , 2006 .

[12]  F. Dryer,et al.  Measurements of dimethyl ether/air mixture burning velocities by using particle image velocimetry , 2004 .

[13]  John B. Heywood,et al.  Internal combustion engine fundamentals , 1988 .

[14]  Seung Hyun Yoon,et al.  Combustion and emission characteristics of DME as an alternative fuel for compression ignition engines with a high pressure injection system , 2008 .

[15]  C. R. Ferguson.  Internal Combustion Engines: Applied Thermosciences , 1986 .

[16]  Seung Hwan Bang,et al.  Experimental Investigation of Spray and Combustion Characteristics of Dimethyl Ether in a Common-Rail Diesel Engine , 2007 .

[17]  J. Simmie,et al.  Burning velocities of dimethyl ether and air , 2001 .

[18]  Mingfa Yao,et al.  Experimental Study on Homogeneous Charge Compression Ignition Combustion With Fuel of Dimethyl Ether and Natural Gas , 2006 .

[19]  Huang Zhen,et al.  Heat Release Analysis on Combustion and Parametric Study on Emissions of HCCI Engines Fueled with 2-Propanol/n-Heptane Blend Fuels , 2006 .

[20]  C. Bae,et al.  The potential of di-methyl ether (DME) as an alternative fuel for compression-ignition engines: A review , 2008 .

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

[22]  C. Lee,et al.  Effect of Premixed Gasoline Fuel on the Combustion Characteristics of Compression Ignition Engine , 2004 .

[23]  Zuo-hua Huang,et al.  Experimental Study on Premixed Combustion of Dimethyl Ether- Hydrogen-Air Mixtures , 2008 .

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