Optical Diagnostics Investigation into the Effect of Pilot Injection Dwell Time and Injection Pressure on Combustion Characteristics and Soot Emissions in a Single-Cylinder Optical Diesel Engine
Publication: Journal of Energy Engineering
Volume 144, Issue 5
Abstract
The present work investigates the effect of the injection dwell time and injection pressure on soot reduction potential in an optical single-cylinder light-duty diesel engine. The engine operated under a double-injection scheme under low load and low engine speed conditions. The conducted experiments considered two different dwell times for three different injection pressures. The fuel quantity of the main injection was adjusted to maintain the same indicated mean effective pressure (IMEP) value among all cases considered. Findings were analyzed via means of pressure trace and apparent heat release rate (AHRR) analyses, as well as a series of optical diagnostics techniques, namely high-speed imaging and planar laser-induced incandescence (pLII). The combination of dwell time and injection pressure substantially affects charge reactivity and soot oxidation potential. The analysis suggests that a shorter dwell time combined with a higher injection pressure can lead to an enhanced potential for engine-out particulate reduction by creating an in-cylinder environment that promotes soot oxidation. Overall, results indicate that a close-coupled pilot and main injection scheme can reduce soot levels, albeit while increasing specific fuel consumption by up to 12% to maintain the same engine power output levels.
Get full access to this article
View all available purchase options and get full access to this article.
Acknowledgments
The authors are thankful to the following people for their contribution over the last years, presented in alphabetical order: Edward Benbow and Asanka Munasinghe from Imperial College and Colin Hall from Obelisk Technology Ltd. The authors from Imperial College would like to acknowledge support from Ford Motor Co. Ltd. UK. The research has also received funding from the People Programme (Marie Curie Actions) of the European Union’s Seventh Framework Programme FP7/2007-2013/ under REA Grant Agreement No. 607214 (ECCO-MATE Project).
References
Aleiferis, P. G., Y. Hardalupas, A. M. K. P. Taylor, K. Ishii, and Y. Urata. 2004. “Flame chemiluminescence studies of cyclic combustion variations and air-to-fuel ratio of the reacting mixture in a lean-burn stratified-charge spark-ignition engine.” Combust. Flame 136 (1–2): 72–90. https://doi.org/10.1016/j.combustflame.2003.09.004.
Amagai, K., Y. Hashimoto, and M. Arai. 1999. “Ignition and combustion characteristics of two-stage injection diesel spray.” JSAE Rev. 20 (3): 407–411. https://doi.org/10.1016/S0389-4304(99)00023-5.
Anders, H., M. Christensen, B. Johansson, A. Franke, M. Richter, and M. Aldén. 1999. A study of the homogeneous charge compression ignition combustion process by chemiluminescence imaging. Warrendale, PA: SAE International.
Bakker, P. C., J. E. De Abreu Goes, L. M. T. Somers, and B. H. Johansson. 2014. Characterization of low load PPC operation using RON70 fuels., 1–13. Warrendale, PA: SAE International.
Beatrice, C., P. Belardini, C. Bertoli, M. G. Lisbona, and M. N. Migliaccio. 2001. “Combustion patterns in common rail D.I. engines inferred by experiments and C.F.D. computations.” Combust. Sci. Technol. 162 (1–6): 235–261. https://doi.org/10.1080/00102200108952143.
Beatrice, C., P. Belardini, C. Bertoli, M. G. Lisbona, and G. M. Rossi Sebastiano. 2002. “Diesel combustion control in common rail engines by new injection strategies.” Int. J. Engine Res. 3 (1): 23–36. https://doi.org/10.1243/1468087021545513.
Bozkurt, M., M. Fikri, and C. Schulz. 2012. “Investigation of the kinetics of OH* and CH* chemiluminescence in hydrocarbon oxidation behind reflected shock waves.” Appl. Phys. B: Lasers Opt. 107 (3): 515–527. https://doi.org/10.1007/s00340-012-5012-y.
Busch, S., K. Zha, P. C. Miles, A. Warey, F. Pesce, R. Peterson, and A. Vassallo. 2015. “Experimental and numerical investigations of close-coupled pilot injections to reduce combustion noise in a small-bore diesel engine.” SAE Int. J. Engines 8 (2): 660–678. https://doi.org/10.4271/2015-01-0796.
Chen, S. K. 2000. Simultaneous reduction of NOx and particulate emissions by using multiple injections in a small diesel engine. Warrendale, PA: SAE International.
Ehleskog, R., R. Ochoterena, and S. Andersson. 2007. Effects of multiple injections on engine-out emission levels including particulate mass from an HSDI diesel engine. Warrendale, PA: SAE International.
Ehleskog, R., and R. L. Ochoterena. 2008. Soot evolution in multiple injection diesel flames. Warrendale, PA: SAE International.
Founti, M., Y. Hardalupas, C. Hong, C. Keramiotis, K. G. Ramaswamy, N. Soulopoulos, A. Taylor, D. P. Touloupis, and G. Vourliotakis. 2015. An experimental investigation on the effect of diluent addition on flame characteristics in a single cylinder optical diesel engine. Warrendale, PA: SAE International.
Gill, K., C. Marriner, K. Sison, and H. Zhao. 2005. In-cylinder studies of multiple diesel fuel injection in a single cylinder optical engine. Warrendale, PA: SAE International.
Han, Z., A. Uludogan, G. Hampson, and R. Reitz. 1996. Mechanism of soot and NOx emission reduction using multiple-injection in a diesel engine. Warrendale, PA: SAE International.
Hardalupas, Y., and M. Orain. 2004. “Local measurements of the time-dependent heat release rate and equivalence ratio using chemiluminescent emission from a flame.” Combust. Flame 139 (3): 188–207. https://doi.org/10.1016/j.combustflame.2004.08.003.
Hong, C. K. H. 2015. Laser induced incandescence and high speed imaging in Hydra optical diesel engine. London: Imperial College.
Johnson, T. 2015. “Review of vehicular emissions trends.” SAE Int. J. Engines 8 (3): 1152–1167. https://doi.org/10.4271/2015-01-0993.
Kathrotia, T., U. Riedel, A. Seipel, K. Moshammer, and A. Brockhinke. 2012. “Experimental and numerical study of chemiluminescent species in low-pressure flames.” Appl. Phys. B: Lasers Opt. 107 (3): 571–584. https://doi.org/10.1007/s00340-012-5002-0.
Koci, C. P., Y. Ra, R. Krieger, M. Andrie, D. E. Foster, R. M. Siewert, and R. P. Durrett. 2009. “Multiple-event fuel injection investigations in a highly-dilute diesel low temperature combustion regime.” SAE Int. J. Engines 2 (1): 837–857. https://doi.org/10.4271/2009-01-0925.
Kohse-Höinghaus, K. 1994. “Laser techniques for the quantitative detection of reactive intermediates in combustion systems.” Prog. Energy Combust. Sci. 20 (3): 203–279. https://doi.org/10.1016/0360-1285(94)90015-9.
Koyanagi, K., H. Öing, G. Renner, and R. Maly. 1999. Optimizing common rail-injection by optical diagnostics in a transparent production type diesel engine. Warrendale, PA: SAE International.
Lee, T., and R. D. Reitz. 2003. The effects of split injection and swirl on a HSDI diesel engine equipped with a common rail injection system. Warrendale, PA: SAE International.
Li, X., C. Guan, Y. Luo, and Z. Huang. 2015. “Effect of multiple-injection strategies on diesel engine exhaust particle size and nanostructure.” J. Aerosol Sci. 89: 69–76. https://doi.org/10.1016/j.jaerosci.2015.07.008.
Liu, Y., and R. D. Reitz. 2005. Optimizing HSDI diesel combustion and emissions using multiple injection strategies. Warrendale, PA: SAE International.
Mingfa, Y., W. Hu, Z. Zunqing, and Y. Yan. 2009. Experimental study of multiple injections and coupling effects of multi-injection and EGR in a HD diesel engine. Warrendale, PA: SAE International.
Musculus, M. P. B., P. C. Miles, and L. M. Pickett. 2013. “Conceptual models for partially premixed low-temperature diesel combustion.” Prog. Energy Combust. Sci. 39 (2–3): 246–283. https://doi.org/10.1016/j.pecs.2012.09.001.
Najafabadi, M. I. 2017. Optical study of stratification for partially premixed combustion. Eindhoven, Netherlands: Technische Universiteit Eindhoven.
Najafabadi, M. I., L. Egelmeers, B. Somers, N. Deen, B. Johansson, and N. Dam. 2017. “The influence of charge stratification on the spectral signature of partially premixed combustion in a light-duty optical engine.” Appl. Phys. B: Lasers Opt. 123 (4): 1–13. https://doi.org/10.1007/s00340-017-6688-9.
Nehmer, D., and R. Reitz. 1994. Measurement of the effect of injection rate and split injections on diesel engine soot and NOx emissions. Warrendale, PA: SAE International.
O’Connor, J., and M. P. B. Musculus. 2013. “Post Injections for soot reduction in diesel engines: A review of current understanding.” SAE Int. J. Engines 6 (1): 400–421.
Ogawa, H., N. Miyamoto C. Li, and A. Sakai. 2000. Improvements of diesel combustion and emissions with two-stage fuel injection at different piston positions. Warrendale, PA: SAE International.
Patterson, M., S. Kong, G. Hampson, and R. Reitz. 1994. Modeling the effects of fuel injection characteristics on diesel engine soot and NOx emissions. Warrendale, PA: SAE International.
Vanegas, A., H. Won, C. Felsch, M. Gauding, and N. Peters. 2008. Experimental investigation of the effect of multiple injections on pollutant formation in a common-rail DI diesel engine. Warrendale, PA: SAE International.
Woschni, G., and J. Fieger. 1979. Determination of local heat transfer coefficients at the piston of a high speed diesel engine by evaluation of measured temperature distribution. Warrendale, PA: SAE International.
Yang, S. Y., and S. H. Chung. 2013. “An experimental study on the effects of high-pressure and multiple injection strategies on DI diesel engine emissions.” Fuel 78: 1303–1317. https://doi.org/10.4271/2013-01-0045.
Zhang, Y., T. Ito, and K. Nishida. 2001. Characterization of mixture formation in split-injection diesel sprays via laser absorption-scattering (LAS) technique. Warrendale, PA: SAE International.
Zhang, Y., and K. Nishida. 2004. “Effect of injection temporal splitting on the characteristics of fuel-air mixture formation in a common rail diesel spray.” Proc. Inst. Mech. Eng. Part D: J. Automobile Eng. 218 (3): 323–331. https://doi.org/10.1243/095440704322955849.
Information & Authors
Information
Published In
Journal of Energy Engineering
Volume 144 • Issue 5 • October 2018
Copyright
©2018 American Society of Civil Engineers.
History
Received: Feb 2, 2018
Accepted: Apr 19, 2018
Published online: Aug 2, 2018
Published in print: Oct 1, 2018
Discussion open until: Jan 2, 2019
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.