Pre-chamber jet ignition is a promising combustion technology to achieve fast combustion in natural gas engines. First, the ignition and combustion characteristics of mixtures in a pre-chamber system with different diameter orifices were studied under engine-relevant pressures and temperatures in a rapid compression machine. The tested fuels, CH4/air stoichiometric mixtures, were diluted by different proportions of CO2/N2 to simulate the corresponding exhaust gas recirculation conditions in engines. High-speed photography was applied to visualize the jet ignition and combustion processes. The experimental results revealed that two ignition patterns existed in the pre-chambers depending on the diameter of orifices. Pre-chamber jet flame ignition pattern appeared when the orifice diameter of the pre-chamber exceeded a critical value, which produced jet flame and ignited the mixtures in the main chamber directly. Pre-chamber jet auto-ignition pattern produced jet which promoted the auto-ignition of mixture in the main chamber when the orifice diameter was smaller and presented much shorter combustion durations. Based on the experimental results in the rapid compression machine, a practical pre-chamber system was designed in a single-cylinder natural gas engine to investigate the combustion performance and emission characteristics. The experimental results indicated appropriate 0.8%–1.4% increases of indicated thermal efficiency were achieved by pre-chamber jet ignition due to the higher combustion efficiency and shorter combustion duration compared to conventional spark ignition. Lower total hydrocarbon and CO emissions but higher NOx emissions were produced by pre-chamber jet ignition due to the faster burning velocity and higher combustion temperature.
KorakianitisTNamasivayamAMCrookesRJ.Natural-gas fueled spark-ignition (SI) and compression-ignition (CI) engine performance and emissions. Prog Energ Combust2011; 37(1): 89–112.
2.
BhandariKBansalAShuklaAKhareM.Performance and emissions of natural gas fueled internal combustion engine: a review. J Sci Ind Res2005; 64(5): 333–338.
3.
SeminRAB. A technical review of compressed natural gas as an alternative fuel for internal combustion engines. Am J Eng Appl Sci2008; 1(4): 302–311.
4.
WeiLGengP.A review on natural gas/diesel dual fuel combustion, emissions and performance. Fuel Process Technol2016; 142: 264–278.
5.
HiremathSSKhandalSVBanapurmathNRMathVBGaitondeVN.Comparative analysis of performance of dual fuel (DF) and homogeneous charge compression ignition (HCCI) engines fuelled with honne oil methyl ester (HOME) and compressed natural gas (CNG). Fuel2017; 196: 134–143.
6.
YousefiAGuoHBiroukM.An experimental and numerical study on diesel injection split of a natural gas/diesel dual-fuel engine at a low engine load. Fuel2018; 212(Suppl. C): 332–346.
7.
SongHLiuCLiFWangZHeXShuaiS, et al. A comparative study of using diesel and PODEn as pilot fuels for natural gas dual-fuel combustion. Fuel2017; 188: 418–426.
MaFDingSWangYWangYWangJZhaoS.Study on combustion behaviors and cycle-by-cycle variations in a turbocharged lean burn natural gas SI engine with hydrogen enrichment. Int J Hydrogen Energ2008; 33(23): 7245–7255.
10.
GharehghaniAKoochakMMirsalimMYusafT.Experimental investigation of thermal balance of a turbocharged SI engine operating on natural gas. Appl Therm Eng2013; 60(1–2): 200–207.
11.
BartolucciLCordinerSMuloneVRoccoV.Natural gas stable combustion under ultra-lean operating conditions in internal combustion engines. Energ Proced2016; 101: 886–892.
12.
ShahzadRNaveenchandranPRashidAAzizA.Characteristics of lean and stoichiometric combustion of compressed natural gas in a direct injection engine. Applied Mechanics and Materials2012; 110–116: 357–369.
13.
IbrahimABariS.Optimization of a natural gas SI engine employing EGR strategy using a two-zone combustion model. Fuel2008; 87(10): 1824–1834.
14.
IbrahimABariS.An experimental investigation on the use of EGR in a supercharged natural gas SI engine. Fuel2010; 89(7): 1721–1730.
15.
HuELiXMengXChenYChengYXieY, et al. Laminar flame speeds and ignition delay times of methane—air mixtures at elevated temperatures and pressures. Fuel2015; 158: 1–10.
16.
RicardoHR.Recent research work on the internal-combustion engine. SAE Trans1922; 17: 1–93.
GussakLKarpovVSlutskiiVSpasskiiA.Burning rate and stability in forechamber flame ignition in an internal-combustion engine. Combust Explos Shock Waves1983; 19(5): 628–630.
19.
MaxsonJAHensingerDMHomKOppenheimAK.Performance of multiple stream pulsed jet combustion systems. SAE technical paper 910565, 1991.
20.
HensingerDMMaxsonJAHomKOppenheimAK.Jet Plume injection and combustion. SAE Trans 1992; 101: 571–580.
21.
WakaiKKitoSSumidaI.Effect of small hydrogen jet flame on augmentation of lean combustion. SAE technical paper 931943, 1993.
22.
RobinetCHigelinPMoreauBPajotOAndrzejewskiJ.A new firing concept for internal combustion engines: “I’APIR.” SAE technical paper 1999-01-0621, 1999.
23.
SasakiHSekiyamaSNakashimaK.A new combustion system of a heat-insulated natural gas engine with a pre-chamber having a throat valve. Int J Engine Res2002; 3(4): 197–208.
24.
ZhengQPZhangHMZhangDF.A computational study of combustion in compression ignition natural gas engine with separated chamber. Fuel2005; 84(12): 1515–1523.
25.
GetzlaffJPapeJGruenigCKuhnertDLatschR. Investigations on pre-chamber spark plug with pilot injection. SAE technical paper 2007-01-0479, 2007.
26.
HeyneSMeierMImbertBFavratD.Experimental investigation of prechamber autoignition in a natural gas engine for cogeneration. Fuel2009; 88(3): 547–552.
27.
AttardWPFraserNParsonsPToulsonE.A turbulent jet ignition pre-chamber combustion system for large fuel economy improvements in a modern vehicle powertrain. SAE Int J Engines2010; 3(2): 20–37.
28.
AttardWPKohnJParsonsP.Ignition energy development for a spark initiated combustion system capable of high load, high efficiency and near zero NOx emissions. SAE Int J Engines2010; 3: 481–496.
29.
AttardWPParsonsP.Flame kernel development for a spark initiated pre-chamber combustion system capable of high load, high efficiency and near zero NOx emissions. SAE Int J Engines2010; 3: 408–427.
30.
AttardWPParsonsP.A normally aspirated spark initiated combustion system capable of high load, high efficiency and near zero NOx emissions in a modern vehicle powertrain. SAE Int J Engines2010; 3(2): 269–287.
31.
AttardWPBlaxillH.A single fuel pre-chamber jet ignition powertrain achieving high load, high efficiency and near zero NOx emissions. SAE Int J Engines2011; 5: 734–746.
32.
AttardWPBlaxillH.A gasoline fueled pre-chamber jet ignition combustion system at unthrottled conditions. SAE Int J Engines2012; 5: 315–329.
33.
AttardWPToulsonEHuisjenAChenXZhuGSchockH.Spark ignition and pre-chamber turbulent jet ignition combustion visualization. SAE technical paper 2012-01-0823, 2012.
34.
ShahATunestalPJohanssonB.Investigation of performance and emission characteristics of a heavy duty natural gas engine operated with pre-chamber spark plug and dilution with excess air and EGR. SAE Int J Engines2012; 5: 1790–1801.
35.
ShahATunestalPJohanssonB. Effect of relative mixture strength on performance of divided chamber “Avalanche Activated Combustion” ignition technique in a heavy duty natural gas engine. SAE technical paper 2014-01-1327, 2014.
36.
ShahATunestalPJohanssonB. Effect of pre-chamber volume and nozzle diameter on pre-chamber ignition in heavy duty natural gas engines. SAE technical paper 2015-01-0867, 2015.
37.
ToulsonEHuisjenAChenXSquibbCZhuGSchockH, et al. Visualization of propane and natural gas spark ignition and turbulent jet ignition combustion. SAE Int J Engines2012; 5: 1821–1835.
38.
TakashimaYTanakaHSakoTFurutaniM.Evaluation of engine performance and combustion in natural gas engine with pre-chamber plug under lean burn conditions. SAE Int J Engines2014; 8: 221–229.
39.
XiongQMoriyoshiYMorikawaKtakahashiYKuboyamaTYamadaT. Improvement in thermal efficiency of lean burn pre-chamber natural gas engine by optimization of combustion system. SAE technical paper 2017-01-0782, 2017.
40.
GentzGThelenBGholarnisheeriMLitkePBrownAHokeJ, et al. A study of the influence of orifice diameter on a turbulent jet ignition system through combustion visualization and performance characterization in a rapid compression machine. Appl Therm Eng2015; 81: 399–411.
41.
GentzGRToulsonE.Experimental studies of a liquid propane auxiliary fueled turbulent jet igniter in a rapid compression machine. SAE Int J Engines2016; 9: 777–785.
42.
GentzGGholamisheeriMToulsonE.A study of a turbulent jet ignition system fueled with iso-octane: pressure trace analysis and combustion visualization. Appl Energ2017; 189: 385–394.
43.
BiswasSQiaoL.Prechamber hot jet ignition of ultra-lean H2/air mixtures: effect of supersonic jets and combustion instability. SAE Int J Engines2016; 9: 1584–1592.
44.
BiswasSTanvirSWangHQiaoL.On ignition mechanisms of premixed CH4/air and H2/air using a hot turbulent jet generated by pre-chamber combustion. Appl Therm Eng2016; 106: 925–937.
45.
BiswasSQiaoL.Ignition of ultra-lean premixed H2/air using multiple hot turbulent jets generated by pre-chamber combustion. Appl Therm Eng2018; 132: 102–114.
46.
QinFShahAHuangZ-WPengL-NTunestalPBaiX-S.Detailed numerical simulation of transient mixing and combustion of premixed methane/air mixtures in a pre-chamber/main-chamber system relevant to internal combustion engines. Combust Flame2018; 188: 357–366.
47.
DiHHeXZhangPWangZWooldridgeMSLawCK, et al. Effects of buffer gas composition on low temperature ignition of iso-octane and n-heptane. Combust Flame2014; 161(10): 2531–2538.
48.
HeywoodJB.Internal combustion engine fundamentals. New York: McGraw-Hill, 1988.
49.
ColemanHGlenn SteeleW. Experimentation, validation, and uncertainty analysis for engineers. Noise Control Engineering Journal2010; 58: 343–344.
50.
SensMBinderEBenzAKramerL. Pre-Chamber ignition as a key technology for highly efficient si engines–new approaches and operating strategies. In: 39th International Vienna motor symposium, Vienna, Austria, April 26, 2018.
51.
IidaNKawaguchiOSatoGT.Premixed flame propagating into a narrow channel at a high speed, part 1: flame behaviors in the channel. Combust Flame1985; 60(3): 245–255.
52.
IidaNKawaguchiOSatoGT.Premixed flame propagating into a narrow channel at a high speed, part 2: transient behavior of the properties of the flowing gas inside the channel. Combust Flame1985; 60(3): 257–267.
53.
SideyJAMMastorakosE. Pre-chamber ignition mechanism: simulations of transient autoignition in a mixing layer between reactants and partially-burnt products. Flow Turbul Combust2018; 101(4): 1093–1102.
54.
LawCK.Combustion physics. New York: Cambridge University Press, 2010.
