This content is not included in your SAE MOBILUS subscription, or you are not logged in.
Effects of Intake Manifold Conditions on Dual-Fuel CNG-Diesel Combustion in a Light Duty Diesel Engine Operated at Low Loads
ISSN: 0148-7191, e-ISSN: 2688-3627
Published April 05, 2016 by SAE International in United States
Annotation ability available
The use of compressed natural gas (CNG) in light duty applications is still restricted to conventional spark ignition engines operating at low compression ratio, so overall efficiency is limited. A combustion concept that has been successfully applied on large stationary engines and to some extent on heavy-duty engines is dual-fuel combustion, where a compression-ignited diesel pilot injection is used to ignite a homogeneous charge of methane gas and air. CNG is injected in the intake ports during the intake stroke and later in the cycle the premixed air-CNG mixture is ignited via a pilot diesel injection close to top dead center. However, this concept has not been applied to a significant extent on light duty engines yet. The main reasons are linked to high temperature methane oxidation requirements and poor combustion efficiency at diluted conditions at low loads. Therefore, in this paper an experimental investigation of the effects of different intake manifold conditions on the dual-fuel combustion process is presented, based on performance and emissions of a light duty diesel engine rebuilt for dual-fuel operation operated at low loads and lean conditions. The main goal is to understand how intake temperature and pressure affects the combustion process and to identify possible control strategies for those parameters over the low load range of operation. Results show that intake air temperature plays an important role in the flame propagation process at highly diluted conditions and higher air temperature allows a sharp reduction in total unburned hydrocarbon emissions (TUHC). Reduced intake air pressure can expand the operating range of lean CNG-Diesel dual-fuel engines by means of greater combustion efficiency, despite higher pumping losses. Maximum gross indicated efficiency recorded during the experiments was 42%. It was possible to run below 4g/kWh TUHC emissions and with high enough exhaust temperature for high efficiency methane oxidation in the aftertreatment system beyond 5 bar IMEPg. Loads ranged between 3 bar and 8 bar IMEPg.
CitationGarcia Valladolid, P. and Tunestal, P., "Effects of Intake Manifold Conditions on Dual-Fuel CNG-Diesel Combustion in a Light Duty Diesel Engine Operated at Low Loads," SAE Technical Paper 2016-01-0805, 2016, https://doi.org/10.4271/2016-01-0805.
- European Environment Agency, “Monitoring of CO2 emissions from passenger cars - Regulation 443/2009,” http://www.eea.europa.eu/, accessed Oct. 2015.
- European Environment Agency, “Regulation (EU) No 333/2014 of the European Parliament and of the Council of 11 March 2014 amending Regulation (EC) No 443/2009 to define the modalities for reaching the 2020 target to reduce CO2 emissions from new passenger cars,” http://eur-lex.europa.eu/, accessed Oct. 2015
- Eurogas, “Long-term Outlook for Gas to 2035”, Brussels, 2013.
- McTaggart-Cowan, G., Mann, K., Wu, N., and Munshi, S., "An Efficient Direct-Injection of Natural Gas Engine for Heavy Duty Vehicles," SAE Technical Paper 2014-01-1332, 2014, doi:10.4271/2014-01-1332.
- McTaggart-Cowan, G., Mann, K., Huang, J., Singh, A. et al., "Direct Injection of Natural Gas at up to 600 Bar in a Pilot-Ignited Heavy-Duty Engine," SAE Int. J. Engines 8(3):981-996, 2015, doi:10.4271/2015-01-0865.
- Zaccardi, J. and Serrano, D., "A Comparative Low Speed Pre-Ignition (LSPI) Study in Downsized SI Gasoline and CI Diesel-Methane Dual Fuel Engines," SAE Int. J. Engines 7(4):1931-1944, 2014, doi:10.4271/2014-01-2688.
- Singh, A., Anderson, D., Hoffman, M., Filipi, Z. et al., "An Evaluation of Knock Determination Techniques for Diesel-Natural Gas Dual Fuel Engines," SAE Technical Paper 2014-01-2695, 2014, doi:10.4271/2014-01-2695.
- Tagai, T., Ishida, M., Ueki, H., and Watanabe, T., "Effects of Equivalence Ratio and Temperature of CNG Premixture on Knock Limit in a Dual Fueled Diesel Engine," SAE Technical Paper 2003-01-1934, 2003, doi:10.4271/2003-01-1934.
- Sasaki, N., Nakata, K., Kawatake, K., Sagawa, S. et al., "The Effect of Fuel Compounds on Pre-ignition under High Temperature and High Pressure Condition," SAE Technical Paper 2011-01-1984, 2011, doi:10.4271/2011-01-1984.
- Taniguchi, S., Masubuchi, M., Kitano, K., and Mogi, K., "Feasibility Study of Exhaust Emissions in a Natural Gas Diesel Dual Fuel (DDF) Engine," SAE Technical Paper 2012-01-1649, 2012, doi:10.4271/2012-01-1649.
- Gottschalk, W., Lezius, U., and Mathusall, L., "Investigations on the Potential of a Variable Miller Cycle for SI Knock Control," SAE Technical Paper 2013-01-1122, 2013, doi:10.4271/2013-01-1122.
- Zoldak, P. and Naber, J., "Spark Ignited Direct Injection Natural Gas Combustion in a Heavy Duty Single Cylinder Test Engine - AFR and EGR Dilution Effects," SAE Technical Paper 2015-01-2808, 2015, doi:10.4271/2015-01-2808.
- EPA, “Methane and Nitrous Oxide Emissions from Natural Source”, 2010. U.S. Environmental Protection Agency, Washington, DC, USA.
- Hirasawa, Y., Tanaka, Y., Banno, Y., and Nagata, M., "Development of Methane Oxidation Catalyst and Its Mechanism," SAE Technical Paper 2005-01-1098, 2005, doi:10.4271/2005-01-1098.
- Liu, B., Checkel, M., Hayes, R., Zheng, M. et al., "Experimental and Modelling Study of Variable Cycle Time for a Reversing Flow Catalytic Converter for Natural Gas/Diesel Dual Fuel Engines," SAE Technical Paper 2000-01-0213, 2000, doi:10.4271/2000-01-0213.
- Königsson F.,”On Combustion in the CNG-Diesel Dual Fuel Engine” Ph.D. thesis, Department of Machina Design, Royal Institute of Technology, Stockholm, 2014.
- Garcia, P. and Tunestal, P., "Experimental Investigation on CNG-Diesel Combustion Modes under Highly Diluted Conditions on a Light Duty Diesel Engine with Focus on Injection Strategy," SAE Int. J. Engines 8(5):2177-2187, 2015, doi:10.4271/2015-24-2439.
- Serrano, D., Obiols, J., and Lecointe, B., "Optimization of Dual Fuel Diesel-Methane Operation on a Production Passenger Car Engine - Thermodynamic Analysis," SAE Technical Paper 2013-01-2505, 2013, doi:10.4271/2013-01-2505.
- Ogawa, H., Zhao, P., Kato, T., and Shibata, G., "Improvement of Combustion and Emissions in a Dual Fuel Compression Ignition Engine with Natural Gas as the Main Fuel," SAE Technical Paper 2015-01-0863, 2015, doi:10.4271/2015-01-0863.
- Andersson, Ö., “Experiment!: Planning, Implementing and Interpreting.” (Wiley, 2012), 178, ISBN: 978-0-470-68825-0
- Königsson, F., Kuyper, J., Stalhammar, P., and Angstrom, H., "The Influence of Crevices on Hydrocarbon Emissions from a Diesel-Methane Dual Fuel Engine," SAE Int. J. Engines 6(2):751-765, 2013, doi:10.4271/2013-01-0848.
- Dronniou, N., Kashdan, J., Lecointe, B., Sauve, K. et al., "Optical Investigation of Dual-fuel CNG/Diesel Combustion Strategies to Reduce CO2 Emissions," SAE Int. J. Engines 7(2):873-887, 2014, doi:10.4271/2014-01-1313.
- Einewall, P. and Johansson, B., "Cylinder to Cylinder and Cycle to Cycle Variations in a Six Cylinder Lean Burn Natural Gas Engine," SAE Technical Paper 2000-01-1941, 2000, doi:10.4271/2000-01-1941.
- Sun, L., liu, Y., Zhou, L., and Zeng, K., "Experimental Investigation of Cycle-by-Cycle Variations in a Natural Gas/Diesel Dual Fuel Engine with EGR," SAE Technical Paper 2013-01-0853, 2013, doi:10.4271/2013-01-0853.
- Dec, J., "A Conceptual Model of DI Diesel Combustion Based on Laser-Sheet Imaging," SAE Technical Paper 970873, 1997, doi:10.4271/970873.
- Pickett, L., Siebers, D., and Idicheria, C., "Relationship Between Ignition Processes and the Lift-Off Length of Diesel Fuel Jets," SAE Technical Paper 2005-01-3843, 2005, doi:10.4271/2005-01-3843.
- Lequien, G., Li, Z., Andersson, O., and Richter, M., "Lift-Off Length in an Optical Heavy-Duty Diesel Engine," SAE Int. J. Engines 8(2):635-646, 2015, doi:10.4271/2015-01-0793.
- Heywood, J.B., “Internal Combustion Engine Fundamentals”, (New York, McGraw-Hill Book Co, 1988), 592, ISBN: 978-0-07-028637-5
- Johansson, B., Andersson, Ö., Tunestål, P., Tunér, M., “Combustion Engines. Volume 1” (Lund, Media-Tryck Lund, 2014), 111, ISBN: 978-91-7623-095-4