Numerical study of combustion characteristics and emissions of a diesel–methane dual-fuel engine for a wide range of injection timings

Computational fluid dynamics simulations are performed to investigate the combustion and emission characteristics of a diesel/natural gas dual-fuel engine. The computational fluid dynamics model is validated against experimental measurements of cylinder pressure, heat release rate, and exhaust emissions from a single-cylinder research engine. The model predictions of in-cylinder diesel spray distribution and location of diesel ignition sites are related to the behavior observed in measured and predicted heat release rate and emissions. Various distributions of diesel fuel inside the combustion chamber are obtained by modifying the diesel injection timing and the spray included angle. Model predictions suggest that the distribution of diesel fuel in the combustion chamber has a significant impact on the characteristics of heat release rate, explaining experimental observations. Regimes of combustion in the dual-fuel engine are identified. Turbulent flame speed calculations, premixed turbulent combustion regime diagram analysis, and high-temperature front propagation speed estimation indicated that the dual-fuel combustion in this engine was supported by successive local auto-ignition and not by turbulent flame propagation.

[1]  M. C. Cameretti,et al.  A numerical and experimental study of dual fuel diesel engine for different injection timings , 2016 .

[2]  Bo Yang,et al.  Simulation of Dual-Fuel-CI and Single-Fuel-SI Engine Combustion Fueled with CNG , 2016 .

[3]  Peng Geng,et al.  A review on natural gas/diesel dual fuel combustion, emissions and performance , 2016 .

[4]  E. S. Guerry,et al.  Injection timing effects on partially premixed diesel–methane dual fuel low temperature combustion , 2016 .

[5]  S. Aggarwal,et al.  Two-stage ignition and NTC phenomenon in diesel engines , 2015 .

[6]  Ke Zeng,et al.  Combustion performance and stability of a dual-fuel diesel–natural-gas engine , 2015 .

[7]  P. K. Senecal,et al.  Modeling Turbulent Combustion Using a RANS Model, Detailed Chemistry, and Adaptive Mesh Refinement , 2014 .

[8]  Hewu Wang,et al.  Effects of pilot fuel quantity on the emissions characteristics of a CNG/diesel dual fuel engine with optimized pilot injection timing , 2013 .

[9]  T. Korakianitis,et al.  Natural-gas fueled spark-ignition (SI) and compression-ignition (CI) engine performance and emissions , 2011 .

[10]  Antonio Paolo Carlucci,et al.  Experimental investigation and combustion analysis of a direct injection dual-fuel diesel–natural gas engine , 2008 .

[11]  Rolf D. Reitz,et al.  Development of a Hybrid, Auto-Ignition/Flame-Propagation Model and Validation Against Engine Experiments and Flame Liftoff , 2007 .

[12]  Rolf D. Reitz,et al.  Development of a Flame Propagation Model for Dual-Fuel Partially Premixed Compression Ignition Engines , 2006 .

[13]  Dimitrios T. Hountalas,et al.  Combustion and exhaust emission characteristics of a dual fuel compression ignition engine operated with pilot Diesel fuel and natural gas , 2004 .

[14]  K. C. Midkiff,et al.  Effect of pilot injection timing, pilot quantity and intake charge conditions on performance and emissions for an advanced low-pilot-ignited natural gas engine , 2004 .

[15]  Song-Charng Kong,et al.  Modeling and experiments of dual-fuel engine combustion and emissions , 2004 .

[16]  Ghazi A. Karim,et al.  Combustion in Gas Fueled Compression: Ignition Engines of the Dual Fuel Type , 2003 .

[17]  Youtong Zhang,et al.  Modeling and Simulation of a Dual Fuel (Diesel/Natural Gas) Engine With Multidimensional CFD , 2003 .

[18]  D. T. Hountalas,et al.  A Simulation Model for the Combustion Process of Natural Gas Engines with Pilot Diesel Fuel as an Ignition Source , 2001 .

[19]  Christopher J. Rutland,et al.  A new droplet collision algorithm , 2000 .

[20]  Peter J. O'Rourke,et al.  A Spray/Wall Interaction Submodel for the KIVA-3 Wall Film Model , 2000 .

[21]  B. Launder,et al.  The numerical computation of turbulent flows , 1990 .

[22]  John B. Heywood,et al.  Flow in the piston-cylinder-ring crevices of a spark-ignition engine: effect on hydrocarbon emissions, efficiency and power , 1982 .

[23]  R. Reitz.  Directions in internal combustion engine research , 2013 .

[24]  David R. Cocker,et al.  Emission rates of regulated pollutants from on-road heavy-duty diesel vehicles , 2006 .

[25]  A. Gosman,et al.  Solution of the implicitly discretised reacting flow equations by operator-splitting , 1986 .