This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Optical Diagnostics of Isobaric and Conventional Diesel Combustion in a Heavy-Duty Diesel Engine
Technical Paper
2022-01-0418
ISSN: 0148-7191, e-ISSN: 2688-3627
Annotation ability available
Sector:
Language:
English
Abstract
Compared to conventional diesel combustion (CDC), isobaric combustion can achieve higher thermal efficiency while lowering heat transfer losses and nitrogen oxides (NOx). However, isobaric combustion suffers from higher soot emissions. While the aforementioned trends are well established, there is limited literature about the high-temperature reaction zones, the liquid-phase penetration distance, and the flame tip propagation velocity of isobaric combustion. In the present study, the line-of-sight integrated imaging of Mie-scattering, combustion luminosity, and CH* chemiluminescence were conducted in an optically accessible single-cylinder heavy-duty diesel engine. The engine was equipped with a flat-bowl-shaped optical piston to allow bottom-view imaging of the combustion chamber. The experiments were conducted using n-heptane fuel for CDC and isobaric combustion modes. The peak cylinder pressure (PCP) and the fuel mean effective pressure (Fuel MEP) for both combustion modes are kept as 70 bar and 19 bar, respectively. For a given combustion mode, flame image velocimetry (FIV) analysis was performed on the consecutive combustion luminosity image pairs to obtain in-flame flow-field details, and the liquid-phase penetration distance and flame tip propagation velocity were also estimated. The combustion luminosity and FIV analysis show that compared to CDC, isobaric combustion has resulted in less prominent flame-flame interactions, which explained the lower heat release rate. Double-injection-based CDC has resulted in a shorter spray penetration distance compared to triple-injection-based isobaric combustion; however, shorter than the boundary of piston-bowl wall. In addition, it was found that CDC has a sudden increase in flame tip propagation velocity preceded by flame propagation due to flame-piston bowl impingement from the second injection and successive movement towards the squish region. However, isobaric combustion showed a trend of constant or slightly decreased flame tip propagation velocity for which the second injection flames remain within the piston bowl wall.
Authors
Topic
Citation
Panthi, N., Goyal, H., AlRamadan, A., Badra, J. et al., "Optical Diagnostics of Isobaric and Conventional Diesel Combustion in a Heavy-Duty Diesel Engine," SAE Technical Paper 2022-01-0418, 2022, https://doi.org/10.4271/2022-01-0418.Also In
References
- Hildingsson , L. , Persson , H. , Johansson , B. , Collin , R. et al. Optical Diagnostics of HCCI and UNIBUS Using 2-D PLIF of OH and Formaldehyde SAE Technical Paper 2005-01-0175 2005 https://doi.org/10.4271/2005-01-0175
- Christensen , M. and Johansson , B. Supercharged Homogeneous Charge Compression Ignition (HCCI) with Exhaust Gas Recirculation and Pilot Fuel SAE Technical Paper 2000-01-1835 2000 https://doi.org/10.4271/2000-01-1835
- Christensen , M. , Johansson , B. , and Einewall , P. Homogeneous Charge Compression Ignition (HCCI) using Isooctane, Ethanol and Natural Gas - A Comparison With Spark Ignition Operation SAE Technical Paper 972874 1997 https://doi.org/10.4271/972874
- Kokjohn , S.L. , Musculus , M.P.B. , and Reitz , R.D. Evaluating Temperature and Fuel Stratification for Heat-Release Rate Control in a Reactivity-Controlled Compression-Ignition Engine Using Optical Diagnostics and Chemical Kinetics Modeling Combustion and Flame 162 6 2015 2729 2742 10.1016/j.combustflame.2015.04.009
- Tang , Q. , Liu , H. , Ran , X. , Li , M. et al. Effects of Direct-Injection Fuel Types and Proportion on Late-Injection Reactivity Controlled Compression Ignition Combustion and Flame 211 2020 445 455 10.1016/j.combustflame.2019.10.018
- Kokjohn , S. , Reitz , R.D. , Splitter , D. , and Musculus , M. Investigation of Fuel Reactivity Stratification for Controlling PCI Heat-Release Rates Using High-Speed Chemiluminescence Imaging and Fuel Tracer Fluorescence SAE International Journal of Engines 5 2 2012 2012-01-0375 10.4271/2012-01-0375
- Goyal , H. , Kook , S. , Hawkes , E. , Chan , Q.N. et al. Influence of Engine Speed on Gasoline Compression Ignition (GCI) Combustion in a Single-Cylinder Light-Duty Diesel Engine SAE Technical Paper 2017-01-0742 2017 https://doi.org/10.4271/2017-01-0742
- Goyal , H. , Kook , S. , and Ikeda , Y. The Influence of Fuel Ignition Quality and First Injection Proportion on Gasoline Compression Ignition (GCI) Combustion in A Small-Bore Engine Fuel 235 2019 10.1016/j.fuel.2018.08.090
- Goyal , H. and Kook , S. Ignition Process of Gasoline Compression Ignition (GCI) Combustion in a Small-Bore Optical Engine Fuel 256 2019 115844 10.1016/j.fuel.2019.115844
- Goyal , H. , Zhang , Y. , Kook , S. , Kim , K.S. et al. Low- to High-Temperature Reaction Transition in a Small-Bore Optical Gasoline Compression Ignition (GCI) Engine SAE International Journal of Engines 12 5 2019 473 488 10.4271/03-12-05-0031
- Goyal , H. , Dyuisenakhmetov , A. , Houidi , M. , Johansson , B. et al. The Effect of Engine Speed, Exhaust Gas Recirculation, and Compression Ratio on Isobaric Combustion SAE International Journal of Engines 13 5 2020 1 13 10.4271/03-13-05-0038
- Dyuisenakhmetov , A. , Goyal , H. , Ben Houidi , M. , Babayev , R. et al. Isobaric Combustion at a Low Compression Ratio SAE Technical Paper 2020-01-0797 2020 https://doi.org/10.4271/2020-01-0797
- Goyal , H. , Panthi , N. , Ben Houidi , M. , Ramadan , A.S. , et al. Performance Analysis and In-Cylinder Visualization of Conventional Diesel and Isobaric Combustion in an Optical Diesel Engine SAE Paper 2021-24-0040 2021 https://doi.org/10.4271/2021-24-0040
- Panthi , N. , Goyal , H. , Ben Houidi , M. , AlRamadan , A.S. et al. Flow-Field Analysis of Isobaric Combustion Using Multiple Injectors in an Optical Accessible Diesel Engine SAE Paper 2021-24-0042 2021 https://doi.org/10.4271/2021-24-0042
- Goyal , H. , Jiminez , C.A. , Nyrenstedt , G. , Im , H. et al. Energy Distribution Analysis of Multiple Injectors for the Double Compression Expansion Engine Concept SAE International Journal of Engines 14 6 2021 1 15 10.4271/03-14-06-0048
- Goyal , H. , Nyrenstedt , G. , Cabezas , K.M. , Panthi , N. et al. A Simulation Study to Understand the Efficiency Analysis of Multiple Injectors for the Double Compression Expansion Engine (DCEE) Concept SAE Technical Paper 2021-01-0444 2021 https://doi.org/10.4271/2021-01-0444
- Jimenez , C.D.A. , Nyrenstedt , G. , Goyal , H. , Andersson , A. et al. Effects of Multiple Injectors on Spray Characteristics and Efficiency in Internal Combustion Engines SAE Technical Paper 2021-01-0501 2021 https://doi.org/10.4271/2021-01-0501
- Okamoto , T. and Uchida , N. New Concept for Overcoming the Trade-Off between Thermal Efficiency, Each Loss and Exhaust Emissions in a Heavy Duty Diesel Engine SAE International Journal of Engines 9 2 2016 10.4271/2016-01-0729
- Uchida , N. and Watanabe , H. A New Concept of Actively Controlled Rate of Diesel Combustion (ACCORDIC): Part II—Simultaneous Improvements in Brake Thermal Efficiency and Heat Loss with Modified Nozzles International Journal of Engine Research 20 1 2019 34 45 10.1177/1468087418820472
- Babayev , R. , Houidi , M. , Andersson , A. , and Johansson , B. Isobaric Combustion: A Potential Path to High Efficiency, in Combination with the Double Compression Expansion Engine (DCEE) Concept SAE Technical Paper 2019-01-0085 2019 https://doi.org/10.4271/2019-01-0085
- Liu , X. , Aljabri , H. , Mohan , B. , Babayev , R. et al. A Numerical Investigation of Isobaric Combustion Strategy in a Compression Ignition Engine International Journal of Engine Research 2020 10.1177/1468087420970376
- Babayev , R. , Houidi , M. , Shankar , V. , Shankar , B. , et al. Injection Strategies for the Isobaric Combustion SAE Technical Paper 2019-01-2267 2019 10.4271/2019-01-2267
- Nyrenstedt , G. , Tang , Q. , Sampath , R. , Alramadan , A. , Houidi , M. , Cenker , E. , Magnotti , G. , and Johansson , B. A Comparative Study of Isobaric Combustion and Conventional Diesel Combustion in Both All-Metal and Optical Engines Fuel 295 120638 1 11 2021 10.1016/j.fuel.2021.120638
- Docquier , N. , Lacas , F. , and Candel , S. Closed-Loop Equivalence Ratio Control of Premixed Combustors Using Spectrally Resolved Chemiluminescence Measurements Proceedings of the Combustion Institute 29 1 2002 139 145 10.1016/S1540-7489(02)80022-0
- Najm , H.N. , Paul , P.H. , Mueller , C.J. , and Wyckoff , P.S. On the Adequacy of Certain Experimental Observables as Measurements of Flame Burning Rate Combustion and Flame 113 3 1998 312 332 10.1016/s0010-2180(97)00209-5
- Tinaut , F.V. , Reyes , M. , Giménez , B. , and Pastor , J.V. Measurements of OH* and CH* Chemiluminescence in Premixed Flames in a Constant Volume Combustion Bomb under Autoignition Conditions Energy and Fuels 25 1 2011 119 129 10.1021/ef1013456
- Liu , Y. , Tan , J. , Wan , M. , Zhang , L. et al. Quantitative Measurement of OH* and CH* Chemiluminescence in Jet Diffusion Flames ACS Omega 5 26 2020 15922 15930 10.1021/acsomega.0c01093
- Tang , Q. , Sampath , R. , Sharma , P. , Nyrenstedt , G. et al. Optical Study on the Fuel Spray Characteristics of the Four-Consecutive-Injections Strategy Used in High-Pressure Isobaric Combustion SAE Technical Paper 2020-01-1129 2020 https://doi.org/10.4271/2020-01-1129
- Kook , S. , Park , S. , and Bae , C. Influence of Early Fuel Injection Timings on Premixing and Combustion in a Diesel Engine Energy and Fuels 22 1 2008 331 337 10.1021/ef700521b
- Aleiferis , P.G. and Rosati , M.F. Controlled Autoignition of Hydrogen in a Direct-Injection Optical Engine Combustion and Flame 159 7 2012 2500 2515 10.1016/j.combustflame.2012.02.021
- Clark , L. , Kook , S. , Chan , Q. , and Hawkes , E. Influence of Injection Timing for Split-Injection Strategies on Well-Mixed High-Load Combustion Performance in an Optically Accessible Spark-Ignition Direct-Injection (SIDI) Engine SAE Technical Paper 2017-01-0657 2017 https://doi.org/10.4271/2017-01-0657