This paper experimentally investigates the impact of EGR on the combustion performance and emissions of methane/hydrogen blends for the diesel pilot ignition (DPI) combustion strategy. Different speed/load cases were evaluated on a single-cylinder compression ignition engine for hydrogen energy shares ranging from 0% to 20%. As hydrogen was added to the premixed mixture, the combustion phasing (CA50) was held constant by either adjusting the pilot start of injection (SOI) timing or using EGR at constant intake pressure (varying premixed equivalence ratio). The experimental results show that the use of EGR at constant intake pressure with methane/hydrogen blends leads to lower unburned hydrocarbon (UHC), carbon-monoxide (CO), and nitric oxide (NO) emissions when compared to the methane-only baseline. Adiabatic flame temperature calculations were used to help explain the observed engine out nitric oxides (NOx) emissions trends. The UHC emissions, however, were significantly higher than the baseline split-injection diesel case due to incomplete combustion and crevice effects. Combustion efficiency improved without a thermal efficiency reduction with hydrogen addition, suggesting that substitution with hydrogen can be beneficial for dual-fuel compression ignition strategies that utilize natural gas. The decay rate for CH4 and H2 was more than linear, which is attributed to the chemical effects of hydrogen addition and EGR.
Abdel-RahmanAA.On the emissions from internal-combustion engines: a review. Int J Energy Res1998; 22(6): 483–513.
2.
MehraRKDuanHJuknelevičiusRMaFLiJ.Progress in hydrogen enriched compressed natural gas (hcng) internal combustion engines - a comprehensive review. Renew Sustain Energ Rev2017; 80: 1458–1498.
3.
ZhangXMyhrvoldNPHausfatherZCaldeiraK.Climate benefits of natural gas as a bridge fuel and potential delay of near-zero energy systems. Appl Energy2016; 167: 317–322.
4.
EPA. Environmental protection agency department of transportation national highway traffic safety administration 49 cfr parts 523, 234, and 535 greehouse gas emissions standards and fuel efficiency standards for medium-and heavy-duty engines and vehicles -ph, 2016.
5.
EPA. Environmental protection agency department of transportation national highway traffic safety administration 49 cfr parts 523, 234, and 535 greehouse gas emissions standards and fuel efficiency standards for medium-and heavy-duty engines and vehicles; fin, 2010.
6.
YuHHuEChengYYangKZhangXHuangZ.Effects of hydrogen addition on the laminar flame speed and markstein length of premixed dimethyl ether–air flames. Energy Fuels2015; 29(7): 4567–4575.
7.
KarimG.Hydrogen as a spark ignition engine fuel. Int J Hydrogen Energy2003; 28(5): 569–577.
8.
VerhelstSWallnerT.Hydrogen-fueled internal combustion engines. Prog Energy Combust Sci2009; 35(6): 490–527.
9.
SalviBLSubramanianKA.Sustainable development of road transportation sector using hydrogen energy system. Renew Sustain Energ Rev2015; 51: 1132–1155.
10.
Al-BreikiMBicerY.Comparative life cycle assessment of sustainable energy carriers including production, storage, overseas transport and utilization. J Clean Prod2021; 279: 123481.
11.
SrinivasanKAgarwalAKrishnanSRMuloneV.Natural gas engines for transportation and power generation. Berlin: Springer, 2019.
WeiLGengP.A review on natural gas/diesel dual fuel combustion, emissions and performance. Fuel Process Technol2016; 142: 264–278.
18.
YousefiAGuoHBiroukM.Effect of diesel injection timing on the combustion of natural gas/diesel dual-fuel engine at low-high load and low-high speed conditions. Fuel2019; 235: 838–846.
19.
MousaviSMSarayRKBahlouliKPoorghasemiKMaghbouliASadeghluA.Effects of pilot diesel injection strategies on combustion and emission characteristics of dual-fuel engines at part load conditions. Fuel2019; 258: 116153.
20.
García ValladolidPTunestålPMonsalve-SerranoJGarcíaAHyvönenJ. Impact of diesel pilot distribution on the ignition process of a dual fuel medium speed marine engine. Energy Convers Manag2017; 149: 192–205.
21.
WangZZhaoZWangD, et al. Impact of pilot diesel ignition mode on combustion and emissions characteristics of a diesel/natural gas dual fuel heavy-duty engine. Fuel2016; 167: 248–256.
22.
WeaverCSTurnerSH.Dual fuel natural gas/diesel engines: technology, performance, and emissions. SAE international paper, 1994.
23.
KahilaHKaarioOAhmadZ, et al. A large-eddy simulation study on the influence of diesel pilot spray quantity on methane-air flame initiation. Combust Flame2019; 206: 506–521.
24.
AndersonMSaloKFridellE.Particle- and gaseous emissions from an LNG powered ship. Environ Sci Technol2015; 49(20): 12568–12575.
25.
UshakovSStenersenDEinangPM.Methane slip from gas fuelled ships: a comprehensive summary based on measurement data. J Mar Sci Technol2019; 24(4): 1308–1325.
26.
TyrewalaDGhandhiJRothamerD. Investigation of premixed fuel composition and pilot reactivity impact on diesel pilot ignition in a single-cylinder compression ignition engine. SAE technical papers, 2023-01-0282, 2023.
27.
Bade ShresthaSKarimG. Hydrogen as an additive to methane for spark ignition engine applications. In: IECEC-97 proceedings of the thirty-second intersociety energy conversion engineering conference, 1997, vol. 2, pp.910–915.
28.
AkansuSKahramanNCeperB.Experimental study on a spark ignition engine fuelled by methane–hydrogen mixtures. Int J Hydrogen Energy2007; 32(17): 4279–4284.
29.
ZhaoRXuLSuX, et al. A numerical and experimental study of marine hydrogen–natural gas–diesel tri–fuel engines. Pol Marit Res2020; 27(4): 80–90.
30.
DimopoulosPRechsteinerCSolticPLaemmleCBoulouchosK.Increase of passenger car engine efficiency with low engine-out emissions using hydrogen–natural gas mixtures: a thermodynamic analysis. Int J Hydrogen Energy2007; 32(14): 3073–3083.
31.
SaravananNNagarajanG.An experimental investigation on manifold-injected hydrogen as a dual fuel for diesel engine system with different injection duration. Int J Energy Res2009; 33(15): 1352–1366.
32.
LiuSWangYZhengZYaoMXieH.Study of the effects of adding hydrogen to diesel/cng dual fuel engine on the emission and fuel consumption. J Combust Sci Technol2003; 9: 539–545.
33.
ChengQAhmadZKaarioOVuorinenVLarmiM.Experimental study on tri-fuel combustion using premixed methane-hydrogen mixtures ignited by a diesel pilot. Int J Hydrogen Energy2021; 46(40): 21182–21197.
34.
ZhouJHCheungCSLeungCW.Combustion, performance and emissions of a diesel engine with h2, ch4 and h2–ch4 addition. Int J Hydrogen Energy2014; 39(9): 4611–4621.
35.
Abu-JraiAMAl-MuhtasebAHHasanAO.Combustion, performance, and selective catalytic reduction of nox for a diesel engine operated with combined tri fuel (h2, ch4, and conventional diesel. Energy2017; 119: 901–910.
36.
AlrazenHAAbu TalibARAhmadKA.A two-component cfd studies of the effects of h2, cng, and diesel blend on combustion characteristics and emissions of a diesel engine. Int J Hydrogen Energy2016; 41(24): 10483–10495.
37.
MansorMRAAbboodMMMohamadTI. The influence of varying hydrogen-methane-diesel mixture ratio on the combustion characteristics and emissions of a direct injection diesel engine. Fuel2017; 190: 281–291.
38.
TyrewalaD.Experimental investigation of low-carbon fuels for use in advanced dual-fuel combustion: diesel pilot ignition. PhD Thesis, University of Wisconsin-Madison, 2024.
39.
SmithGGoldenDFrenklachM, et al. Gri-mech 3.0.
40.
BayliffSWindomBMarcheseA, et al. Controlled end gas auto ignition with exhaust gas recirculation on a stoichiometric, spark ignited, natural gas engine. In: Internal combustion engine division fall technical conference, 2020, vol. 84034, p.V001T03A011. American Society of Mechanical Engineers.
41.
BayliffSM.Evaluation of controlled end gas auto ignition with exhaust gas recirculation in a stoichiometric, spark ignited, natural gas engine. Master’s Thesis, Colorado State University, 2020.
42.
HampsonGJ.High efficiency natural gas engine combustion using controlled auto-ignition. In: Internal combustion engine division fall technical conference, 2019, vol. 59346, p.V001T03A019. American Society of Mechanical Engineers.
43.
SanliAYılmazITGümüşM.Assessment of combustion and exhaust emissions in a common-rail diesel engine fueled with methane and hydrogen/methane mixtures under different compression ratio. Int J Hydrogen Energy2020; 45(4): 3263–3283.
