Flame Kernel Growth and Related Effects of Spark Plug Electrodes: Fluid Motion Interaction in an Optically Accessible DISI Engine
One of the aspects that are usually neglected during the design phase of an engine is the effect of the spark plug on the flow field inside the combustion chamber. Because of the difficulties in the experimental investigation of the mutual interaction between flow alteration and early flame kernel convection effect inside the engine combustion chamber, CFD-3D simulation is usually exploited in such cases. Experimentally speaking, a particular type of engine has to be used in order to directly observe the flame propagation process. In this study, a double electrode spark plug was fitted into an optically accessible engine and a high-speed camera was used to capture the initial stages of the combustion process. Both the arc and the kernel phases were observed. Then, a morphologic analysis was carried out and the position of the center of mass of the flame, relative to the spark plug position, was calculated. The crossflow orientation was chosen for the spark plug and the kernel growth process was observed for different air-fuel ratios. It was observed that during a normal cycle the flow field between the electrodes tends to transport the arc deforming it. Because of that, the kernel growth phase takes place away from the electrodes and the flame propagates with a preferential direction dictated by the flow field.
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 Communication from the Commission to the European Parliament, the European Council, the Council, the European Economic and Social Committee, the Committee of the Regions and the European Investment Bank. A Clean Planet for all A European strategic long-term vision for a prosperous, modern, competitive and climate neutral economy COM/2018/773 final.
 Ferrari, Giancarlo Internal Combustion Engines, Società Editoriale Esculapio, 2016, pp. 471-519.
 Cimarello, A. (a.a. 2014-2015). Analysis of Advanced Ignition Systems in Leaning Operating Conditions using an Optical Access Engine. Tesi di dottorato. Università degli Studi di Perugia, Dipartimento di Ingegneria.
 Ozdor, N., Dulger, M., and Sher, E., “Cyclic Variability in Spark Ignition Engines: A Literature Survey,” SAE Technical Paper 940987, 1994, 10.4271/940987.
 Fontanesi, S., d’Adamo, A., Rutland, C.J., "Large-Eddy simulation analysis of spark configuration effect on cycle-to-cycle variability of combustion and knock", International Journal of Engine Research, 2015, doi:10.1177/1468087414566253.
 d'Adamo, Alessandro & Breda, Sebastiano & Berni, Fabio & Fontanesi, Stefano. (2018). Understanding the Origin of Cycle-to-Cycle Variation Using Large-Eddy Simulation: Similarities and Differences between a Homogeneous Low-Revving Speed Research Engine and a Production DI Turbocharged Engine. SAE International Journal of Engines. 12. 10.4271/03-12-01-0007.
 Schiffmann, P., “Root Causes of Cycle-To-Cycle Combustion Variations in Spark Ignited Engines,” Ph.D. thesis, University of Michigan, Ann Arbor, MI, USA, 2016.
 Ge, Haiwen & Zhao, Peng. (2019). Numerical Investigation of the Spark Plug Orientation Effects on Flame Kernel Growth. 10.4271/2019-01-0005.
 Shekhawat, Yajuvendra & Haworth, D.C. & d'Adamo, Alessandro & Berni, F. & Fontanesi, Stefano & Schiffmann, Philipp & Reuss, David & Sick, V.. (2017). An Experimental and Simulation Study of Early Flame Development in a Homogeneous-charge Spark-Ignition Engine. Oil and Gas Science and Technology. 72. 10.2516/ogst/2017028.
 Wang, Yanyu, et al. “Investigation of Impacts of Spark Plug Orientation on Early Flame Development and Combustion in a DI Optical Engine.” SAE International Journal of Engines, vol. 10, no. 3, 2017, pp. 995–1010. JSTOR, www.jstor.org/stable/26285106. Accessed 27 Jan. 2020.
 Aleiferis, P., Taylor, A., Whitelaw, J., Ishii, K. et al., "Cyclic Variations of Initial Flame Kernel Growth in a Honda VTEC-E Lean-Burn Spark-Ignition Engine," SAE Technical Paper 2000-01-1207, 2000, https://doi.org/10.4271/2000-01-1207.
 Anderson, R. W., and J. R. Asik. “Ignitability Experiments in a Fast Burn, Lean Burn Engine.” SAE Transactions, vol. 92, 1983, pp. 390–404. JSTOR, www.jstor.org/stable/44668078. Accessed 27 Jan. 2020.
 Bowditch, F., “A New Tool for Combustion Research A Quartz Piston Engine,” SAE Technical Paper 610002, 1961, doi:10.4271/610002.
 Irimescu, A., Merola, S., and Martinez, S., "Influence of Engine Speed and Injection Phasing on Lean Combustion for Different Dilution Rates in an Optically Accessible Wall-Guided Spark Ignition Engine," SAE Int. J. Engines 11(6):1343-1369, 2018, https://doi.org/10.4271/2018-01-1421.
 Merola, S.S., Marchitto, L., Tornatore, C., Valentino, G., and Irimescu, A., “Optical Characterization of Combustion Processes in a DISI Engine Equipped with Plasma-Assisted Ignition System,” Appl. Therm. Eng. 69(1-2):177-187, 2014, doi:10.1016/j.applthermaleng.2014.04.046.
 Irimescu, A.; Marchitto, L.; Merola, S.S.; Tornatore, C.; Valentino, G. Evaluation of different methods for combined thermodynamic and optical analysis of combustion in spark ignition engines. Energy onvers. Manag. 2014, 87, 914–927, doi:10.1016/j.enconman.2014.07.037.
 Martinez, S.; Irimescu, A.; Merola, S.; Lacava, P.; Curto, P. Flame Front Propagation in an Optical GDI Engine under Stoichiometric and Lean Burn Conditions. Energies 2017, 10, 1337, doi:10.3390/en10091337.
 Heywood, John B. Internal Combustion Engine Fundamentals. New York: McGraw-Hill, 1988, pp. 392.