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New Fuels and Advanced Combustion Modes for Innovative Internal Combustion Engines

A special issue of Energies (ISSN 1996-1073). This special issue belongs to the section "I2: Energy and Combustion Science".

Deadline for manuscript submissions: closed (30 September 2024) | Viewed by 17414

Special Issue Editors


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Guest Editor
Department of Civil and Mechanical Engineering, University of Cassino and Southern Latium, 03043 Cassino, Italy
Interests: energy systems analyses and development; internal combustion engine modeling and testing; alternative fuels
Special Issues, Collections and Topics in MDPI journals

E-Mail Website
Guest Editor
Department of Civil and Mechanical Engineering, University of Cassino and Southern Latium, 03043 Cassino, Italy
Interests: carbon-free fuels; biofuels; combustion analysis; 1D engine modeling; 3D combustion simulation
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Today, the need to reduce both greenhouse gas and pollutant emissions is a challenge for the whole energy sector. This leads to both the introduction of new technologies and the improvement of the most widely used, traditional ones. Among the latter, internal combustion engines (ICEs) provide about 25% of the world power today. In particular, the whole transport sector is largely based on this technology. The replacement of ICEs with combustion-less technologies appears to be a tough challenge from both a technical and economic point of view. It seems difficult to achieve this goal in a short time on a global scale. Furthermore, the impact of all technologies still needs to be carefully assessed by considering their entire life and use cycle.

Thus, ICEs may still play an important role in the near future. It is still important to continue to develop them in order to increase the transport sector sustainability.

The environmental impact of ICEs can be reduced, exploiting new fuels and investigating innovative combustion modes. Carbon-free fuels (hydrogen and ammonia), low-carbon fuels (methane, methanol, etc.), e-fuels, and biofuels can strongly contribute to reduce greenhouse gas and pollutant emissions. Considering both conventional and non-conventional fuels, advanced combustion strategies (HCCI, RCCI, TJI, etc.) can improve the energy conversion efficiency.

This Special Issue aims to present and disseminate the most recent advances related to the design, experimentation, and modeling of conventional and innovative internal combustion engines fueled by both conventional and new fuels.

Topics of interest for publication include but are not limited to:

  • Potential and limits of new fuels in ICEs;
  • Innovative combustion modes (HCCI, RCCI, TJI, etc.);
  • Novel developments of conventional combustion modes (SI and CI);
  • Developments of fuel injection systems;
  • Well-to-wheel and life cycle assessment of ICE-based vehicles running with both conventional and new fuels.

Dr. Enzo Galloni
Dr. Davide Lanni
Guest Editors

Manuscript Submission Information

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Keywords

  • internal combustion engines
  • carbon-free fuels
  • e-fuels
  • biofuels
  • advanced combustion modes
  • fuel injection systems
  • well-to-wheel
  • life cycle assessment

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Related Special Issue

Published Papers (11 papers)

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Research

Jump to: Review

19 pages, 2231 KiB  
Article
A New Method of Failure Mode and Severity Effects Analysis for Hydrogen-Fueled Combustion Systems
by Adrian Gill, Ireneusz Pielecha and Filip Szwajca
Energies 2024, 17(19), 4802; https://doi.org/10.3390/en17194802 - 25 Sep 2024
Viewed by 527
Abstract
This article aims to align its content with current trends in hybrid risk analysis methods while utilizing experimental research. This paper presents a hybrid methodology for analyzing the failure severity of a two-stage hydrogen-powered combustion system and details its implementation. This methodology assumes [...] Read more.
This article aims to align its content with current trends in hybrid risk analysis methods while utilizing experimental research. This paper presents a hybrid methodology for analyzing the failure severity of a two-stage hydrogen-powered combustion system and details its implementation. This methodology assumes the use of the original FMESA method (Failure Mode and Effects Severity Analysis) with dedicated tabular scales of the failure severity. Obtaining results under the FMESA using experimental research is intended to reduce epistemic uncertainty, which is an important component of hazard severity or risk models. Its essence is to change the way of obtaining the results of the basic components of known methods such as FMEA/FMECA (Failure Mode and Effect Analysis/Failure Mode, Effects and Criticality Analysis). Experimental research was also used to develop the original failure severity scales for a two-stage hydrogen-fueled combustion system. The article presents a review of the literature on methods for identifying and analyzing hazards in hydrogen systems, the FMESA method with its mathematical model, results in the form of tabular scales of the failure severity, results of selected experimental tests, and quantitative results of a severity analysis of eleven failure modes of a two-stage hydrogen-fueled combustion system for a selected engine operating point. Full article
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16 pages, 3507 KiB  
Article
Influence of Performance Packages on Fuel Consumption and Exhaust Emissions of Passenger Cars and Commercial Vehicles under WLTP
by Luca Marchitto, Maria Antonietta Costagliola and Alessandra Berra
Energies 2024, 17(14), 3356; https://doi.org/10.3390/en17143356 - 9 Jul 2024
Viewed by 975
Abstract
The transportation sector is responsible for about 16% of worldwide greenhouse gas emissions. Despite efforts for a sensible reduction by means of new technologies’ development, the average age of a vehicle fleet is 12.3 years in the European Union. In light of this, [...] Read more.
The transportation sector is responsible for about 16% of worldwide greenhouse gas emissions. Despite efforts for a sensible reduction by means of new technologies’ development, the average age of a vehicle fleet is 12.3 years in the European Union. In light of this, actions aiming at improving the efficiency of circulating vehicles can prove effective in the short to mid-term. Introducing performance packages in standard fuels could allow a reduction in the CO2 emissions of whole vehicle fleets without any modification to powertrain. Such a kind of additive is generally used in premium fuels; deposit control additives can reduce or control the deposits at intake valves and at nozzle holes with benefits for the fuel efficiency and exhaust emissions. Further improvements in combustion phasing can be achieved with cetane/octane improver. This paper aims to assess the influence of two performance packages on the exhaust emissions and fuel consumption of five vehicles set to be as representative as possible of circulating Italian passenger cars and light commercial fleet vehicles (LCVs). Based on the literature datasets, three Euro 4 vehicles were selected with a mileage representative of each single vehicle class: two passenger cars (one spark ignition and one diesel) and an LCV. Further, two diesel Euro 6 vehicles, a passenger car and an LCV, were tested to investigate the effect of fuel additives on the combustion of vehicles compliant with current homologation regulation. Exhaust emissions and fuel consumption were experimentally estimated on a chassis dynamometer over a worldwide harmonized light vehicles test cycle (WLTC) in a climate-controlled laboratory. Each vehicle was preliminarily tested when running with base fuel, then a 3000 km clean-up stage was performed using the additive package. Finally, WLTC tests were repeated. Results demonstrated the efficiency of the performance packages with a reduction between 1.2% (diesel Euro 6 passenger car) and 8.1% (diesel Euro 4 passenger car) in fuel consumption. Similar trends were found for CO2 emissions. Further, a sensible reduction in THCs, CO and PM was found for each vehicle class. Full article
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14 pages, 2927 KiB  
Article
A Complete Assessment of the Emission Performance of an SI Engine Fueled with Methanol, Methane and Hydrogen
by Francesco Catapano, Silvana Di Iorio, Agnese Magno, Paolo Sementa and Bianca Maria Vaglieco
Energies 2024, 17(5), 1026; https://doi.org/10.3390/en17051026 - 22 Feb 2024
Cited by 2 | Viewed by 1030
Abstract
This study explores the potentiality of low/zero carbon fuels such as methanol, methane and hydrogen for motor applications to pursue the goal of energy security and environmental sustainability. An experimental investigation was performed on a spark ignition engine equipped with both a port [...] Read more.
This study explores the potentiality of low/zero carbon fuels such as methanol, methane and hydrogen for motor applications to pursue the goal of energy security and environmental sustainability. An experimental investigation was performed on a spark ignition engine equipped with both a port fuel and a direct injection system. Liquid fuels were injected into the intake manifold to benefit from a homogeneous charge formation. Gaseous fuels were injected in direct mode to enhance the efficiency and prevent abnormal combustion. Tests were realized at a fixed indicated mean effective pressure and at three different engine speeds. The experimental results highlighted the reduction of CO and CO2 emissions for the alternative fuels to an extent depending on their properties. Methanol exhibited high THC and low NOx emissions compared to gasoline. Methane and, even more so, hydrogen, allowed for a reduction in THC emissions. With regard to the impact of gaseous fuels on the NOx emissions, this was strongly related to the operating conditions. A surprising result concerns the particle emissions that were affected not only by the fuel characteristics and the engine test point but also by the lubricating oil. The oil contribution was particularly evident for hydrogen fuel, which showed high particle emissions, although they did not contain carbon atoms. Full article
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14 pages, 3231 KiB  
Article
Retrofit of Diesel Engines with H2 for Potential Decarbonization of Non-Electrified Railways: Assessment with Lifecycle Analysis and Advanced Numerical Modeling
by Mehrshad Kolahchian Tabrizi, Tarcisio Cerri, Davide Bonalumi, Tommaso Lucchini and Morris Brenna
Energies 2024, 17(5), 996; https://doi.org/10.3390/en17050996 - 20 Feb 2024
Cited by 1 | Viewed by 1335
Abstract
The application of hydrogen in heavy-duty vehicles or trains has been suggested as a promising solution to decarbonize the transportation sector. In this study, a one-dimensional engine modeling is employed to evaluate the potential of hydrogen as a fuel for railway applications. A [...] Read more.
The application of hydrogen in heavy-duty vehicles or trains has been suggested as a promising solution to decarbonize the transportation sector. In this study, a one-dimensional engine modeling is employed to evaluate the potential of hydrogen as a fuel for railway applications. A turbocharged diesel engine is simulated as the baseline unit, and the results are validated with experimental data. The same engine is converted to become compatible with hydrogen through some modifications in the turbocharger group and the injection and ignition systems to preserve the performance of the baseline configuration. The findings show that the engine traction power is reduced from 600 to 400 kW, indicating an inferior performance for the hydrogen-fueled engine. The energy consumption of the hydrogen-fueled engine on a real train mission profile is almost two times the diesel version. However, our Life Cycle Assessment analysis with a Well-to-Wheel system boundary shows a 56% reduction in equivalent CO2 emissions for the engine fueled with photovoltaic-based green hydrogen. Substituting diesel with low-carbon hydrogen can decrease the train’s carbon footprint from 4.27 to even less than 2 kg CO2 eq./km, suggesting that moderately modified engines are a promising solution for decarbonizing non-feasibly electrified railway sections. Full article
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31 pages, 10613 KiB  
Article
A New Generation of Hydrogen-Fueled Hybrid Propulsion Systems for the Urban Mobility of the Future
by Ivan Arsie, Michele Battistoni, Pier Paolo Brancaleoni, Roberto Cipollone, Enrico Corti, Davide Di Battista, Federico Millo, Alessio Occhicone, Benedetta Peiretti Paradisi, Luciano Rolando and Jacopo Zembi
Energies 2024, 17(1), 34; https://doi.org/10.3390/en17010034 - 20 Dec 2023
Cited by 10 | Viewed by 1870
Abstract
The H2-ICE project aims at developing, through numerical simulation, a new generation of hybrid powertrains featuring a hydrogen-fueled Internal Combustion Engine (ICE) suitable for 12 m urban buses in order to provide a reliable and cost-effective solution for the abatement of both CO [...] Read more.
The H2-ICE project aims at developing, through numerical simulation, a new generation of hybrid powertrains featuring a hydrogen-fueled Internal Combustion Engine (ICE) suitable for 12 m urban buses in order to provide a reliable and cost-effective solution for the abatement of both CO2 and criteria pollutant emissions. The full exploitation of the potential of such a traction system requires a substantial enhancement of the state of the art since several issues have to be addressed. In particular, the choice of a more suitable fuel injection system and the control of the combustion process are extremely challenging. Firstly, a high-fidelity 3D-CFD model will be exploited to analyze the in-cylinder H2 fuel injection through supersonic flows. Then, after the optimization of the injection and combustion process, a 1D model of the whole engine system will be built and calibrated, allowing the identification of a “sweet spot” in the ultra-lean combustion region, characterized by extremely low NOx emissions and, at the same time, high combustion efficiencies. Moreover, to further enhance the engine efficiency well above 40%, different Waste Heat Recovery (WHR) systems will be carefully scrutinized, including both Organic Rankine Cycle (ORC)-based recovery units as well as electric turbo-compounding. A Selective Catalytic Reduction (SCR) aftertreatment system will be developed to further reduce NOx emissions to near-zero levels. Finally, a dedicated torque-based control strategy for the ICE coupled with the Energy Management Systems (EMSs) of the hybrid powertrain, both optimized by exploiting Vehicle-To-Everything (V2X) connection, allows targeting H2 consumption of 0.1 kg/km. Technologies developed in the H2-ICE project will enhance the know-how necessary to design and build engines and aftertreatment systems for the efficient exploitation of H2 as a fuel, as well as for their integration into hybrid powertrains. Full article
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18 pages, 2183 KiB  
Article
Ammonia Combustion in a Spark-Ignition Engine Supported with Dimethyl Ether
by Wojciech Tutak, Michał Pyrc, Michał Gruca and Arkadiusz Jamrozik
Energies 2023, 16(21), 7283; https://doi.org/10.3390/en16217283 - 26 Oct 2023
Cited by 5 | Viewed by 1471
Abstract
This paper presents the results of experimental tests with a spark-ignition engine powered using ammonia and DME (dimethyl ether). The tests were carried out on a CFR (cooperative fuel research) engine with a compression ratio of 10 and a rotational speed of 600 [...] Read more.
This paper presents the results of experimental tests with a spark-ignition engine powered using ammonia and DME (dimethyl ether). The tests were carried out on a CFR (cooperative fuel research) engine with a compression ratio of 10 and a rotational speed of 600 rpm. DME was used as a fuel to facilitate the initiation and then accelerate the combustion in the SI (spark-ignition) engine. It turned out that only about 10% of the energy share of DME ensures the correct combustion process. DME has a positive effect on the combustion stages, reduces the ignition delay time, and shortens the combustion duration. Thanks to this, for 18% of the energy share of NH3, the highest engine efficiency (29.8%), the highest value of the average indicated pressure IMEP (712 kPa), and the minimum value of specific energy consumption (12.1 MJ/kWh) were obtained. Even the smallest DME content ensured the high repeatability of IMEP, below the permissible limit of 5%. Full article
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18 pages, 7161 KiB  
Article
Turpentine as an Additive for Diesel Engines: Experimental Study on Pollutant Emissions and Engine Performance
by Robert Mădălin Chivu, Jorge Martins, Florin Popescu, Krisztina Uzuneanu, Ion V. Ion, Margarida Goncalves, Teodor-Cezar Codău, Elena Onofrei and Francisco P. Brito
Energies 2023, 16(13), 5150; https://doi.org/10.3390/en16135150 - 4 Jul 2023
Cited by 5 | Viewed by 2526
Abstract
The need for reducing fossil fuel consumption and greenhouse gas (GHG) emissions in internal combustion engines has raised the opportunity for the use of renewable energy sources. For the progressive replacement of fossil fuels like diesel, those derived from the sustainable management of [...] Read more.
The need for reducing fossil fuel consumption and greenhouse gas (GHG) emissions in internal combustion engines has raised the opportunity for the use of renewable energy sources. For the progressive replacement of fossil fuels like diesel, those derived from the sustainable management of forest resources may be a good option. In Portugal, pine trees (pinus pinaster) are among the most widely cultivated tree species. Turpentine can be extracted from their sap without harming the tree. Turpentine is known to be a good fuel with a lower viscosity than regular diesel but with a comparable caloric value, boiling point and ignition characteristics, although it is not widely used as a compression ignition fuel. Moreover, recent research has highlighted the possibility of substantially increasing the turpentine yield through biotechnology, bringing it closer to economic viability. The present study investigates the performance, pollutant emissions and fuel consumption of a 1.6 L four-cylinder direct-injection diesel engine operating with several blends of commercial diesel fuel and turpentine obtained from pine trees. The aim of this study was to assess whether it would be possible to maintain or even improve the performance, fuel consumption and GHG and pollutant emissions (HC, NOx, CO and PM) of the engine with the partial incorporation of this biofuel. Turpentine blends of up to 30% in substitution of regular diesel fuel were tested. The main novelties of the present work are related to (i) the careful testing of a still-insufficiently studied fuel that could gain economical attractiveness with the recent developments in yield improvement through biotechnology and (ii) the tests conducted under fixed engine load positions typical of road and highway conditions. The addition of this biofuel only slightly impacted the engine performance parameters. However, a slightly positive effect was observed in terms of torque, with an increase of up to 7.9% at low load for the 15T85D mixture and 6.8% at high load being observed. Power registered an increase of 9% for the 15T85D mixture at low speed and an increase of 5% for the 30T70D mixture at high speed when compared to the reference fuel (commercial diesel fuel). While the efficiency and fossil GHG emissions were improved with the incorporation of turpentine, it had a mixed effect on polluting emissions such as unburned hydrocarbons (HC) and smoke (PM) and a negative effect on nitrogen oxides (NOx). NOx emissions increased by 30% for high loads and 20% for low loads, mainly as an indirect effect of the improvement in the engine performance and not so much as a consequence of the marginally higher oxygen content of turpentine relative to commercial diesel fuel. Full article
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18 pages, 4399 KiB  
Article
Co-Combustion of Hydrogen with Diesel and Biodiesel (RME) in a Dual-Fuel Compression-Ignition Engine
by Wojciech Tutak, Arkadiusz Jamrozik and Karol Grab-Rogaliński
Energies 2023, 16(13), 4892; https://doi.org/10.3390/en16134892 - 23 Jun 2023
Cited by 7 | Viewed by 1922
Abstract
The utilization of hydrogen for reciprocating internal combustion engines remains a subject that necessitates thorough research and careful analysis. This paper presents a study on the co-combustion of hydrogen with diesel fuel and biodiesel (RME) in a compression-ignition piston engine operating at maximum [...] Read more.
The utilization of hydrogen for reciprocating internal combustion engines remains a subject that necessitates thorough research and careful analysis. This paper presents a study on the co-combustion of hydrogen with diesel fuel and biodiesel (RME) in a compression-ignition piston engine operating at maximum load, with a hydrogen content of up to 34%. The research employed engine indication and exhaust emissions measurement to assess the engine’s performance. Engine indication allowed for the determination of key combustion stages, including ignition delay, combustion time, and the angle of 50% heat release. Furthermore, important operational parameters such as indicated pressure, thermal efficiency, and specific energy consumption were determined. The evaluation of dual-fuel engine stability was conducted by analyzing variations in the coefficient of variation in indicated mean effective pressure. The increase in the proportion of hydrogen co-combusted with diesel fuel and biodiesel had a negligible impact on ignition delay and led to a reduction in combustion time. This effect was more pronounced when using biodiesel (RME). In terms of energy efficiency, a 12% hydrogen content resulted in the highest efficiency for the dual-fuel engine. However, greater efficiency gains were observed when the engine was powered by RME. It should be noted that the hydrogen-powered engine using RME exhibited slightly less stable operation, as measured by the COVIMEP value. Regarding emissions, hydrogen as a fuel in compression ignition engines demonstrated favorable outcomes for CO, CO2, and soot emissions, while NO and HC emissions increased. Full article
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15 pages, 18925 KiB  
Article
A CFD Modelling Approach for the Operation Analysis of an Exhaust Backpressure Valve Used in a Euro 6 Diesel Engine
by Francisco J. Martos, José A. Soriano, Andrei Braic, Pablo Fernández-Yáñez and Octavio Armas
Energies 2023, 16(10), 4112; https://doi.org/10.3390/en16104112 - 16 May 2023
Cited by 4 | Viewed by 1622
Abstract
Harvesting residual thermal energy from exhaust gases with thermoelectric generators is one of the paths that are currently being explored to achieve more sustainable and environmentally friendly means of transport. In some cases, thermoelectric generators are installed in a by-pass configuration to regulate [...] Read more.
Harvesting residual thermal energy from exhaust gases with thermoelectric generators is one of the paths that are currently being explored to achieve more sustainable and environmentally friendly means of transport. In some cases, thermoelectric generators are installed in a by-pass configuration to regulate the mass flow entering the thermoelectric generator. Some manufacturers are using throttle valves with electromechanical actuators and electronic control in the exhaust pipe to improve techniques for active control of pollutant emissions in reciprocating internal combustion engines, such as the exhaust gas recirculation. The above-mentioned circumstances have motivated the approach of this work: computational fluid dynamics (CFD) modelling of the operation of a throttle valve used for establishing adequate exhaust backpressure conditions to achieve the low pressure exhaust gas recirculation in Euro 6 engines. The aim of this model is to understand the flow control process with these types of valves in order to incorporate them in an exhaust system that will include two thermoelectric generators used to convert residual thermal energy into electrical energy. This work presents a computational model of the flow through the throttle valve under different temperatures and mass flow rates of the exhaust gas with different closing positions. For all cases, the values of the pressure drop were obtained. In all cases studied, the level of agreement between the modelled and experimental results exceeds 90%. The developed model has helped to propose a correlation to estimate the mass flow rate of exhaust gas from easily measurable quantities. Full article
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17 pages, 4766 KiB  
Article
Assessment of the Operation of an SI Engine Fueled with Ammonia
by Davide Lanni, Enzo Galloni, Gustavo Fontana and Gabriele D’Antuono
Energies 2022, 15(22), 8583; https://doi.org/10.3390/en15228583 - 16 Nov 2022
Cited by 14 | Viewed by 1892
Abstract
Recently, the research interest regarding ammonia applications in energy systems has been increasing. Ammonia is an important hydrogen carrier that can also be obtained starting from renewable energy sources. Furthermore, ammonia can be used as a carbon-free fuel in combustion systems. In particular, [...] Read more.
Recently, the research interest regarding ammonia applications in energy systems has been increasing. Ammonia is an important hydrogen carrier that can also be obtained starting from renewable energy sources. Furthermore, ammonia can be used as a carbon-free fuel in combustion systems. In particular, the behavior of internal combustion engines (ICEs), fueled by ammonia, needs to be further investigated. The main disadvantage of this kind of fuel is its low laminar flame speed when it is oxidized with air. On the other hand, considering a spark-ignition (SI) engine, the absence of knock phenomena could allow a performance improvement. In this work, a 1D numerical approach was used in order to assess the performance and the operating limits of a downsized PFI SI engine fueled with pure ammonia. Furthermore, the reliability of the 1D model was verified by means of a 3D approach. Both throttled and unthrottled engine operation was investigated. In particular, different boost levels were analyzed under WOT (wide-open throttle) conditions. The potential of the 1D approach was also exploited to evaluate the effect of different geometrical compression ratio on the ammonia engine behavior. The results show that the low laminar flame speed of ammonia–air mixtures leads to increased combustion durations and optimal spark timings more advanced than the typical ones of SI engines. On the other hand, knock phenomena are always avoided. Due to the engine operating limits, the maximum rotational speed guaranteeing proper engine operation is 3000 rpm, except for at the highest boost level. At this regime, the load regulation can be critical in terms of unburned fuel emissions. Considering increased compression ratios and no boost conditions, even the 4000 rpm operating point guarantees proper engine operation. Full article
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Review

Jump to: Research

39 pages, 23218 KiB  
Review
CFD Simulation of Pre-Chamber Spark-Ignition Engines—A Perspective Review
by Soo-Jin Jeong
Energies 2024, 17(18), 4696; https://doi.org/10.3390/en17184696 - 20 Sep 2024
Viewed by 718
Abstract
The growing demand to reduce emissions of pollutants and CO2 from internal combustion engines has led to a critical need for the development of ultra-lean burn engines that can maintain combustion stability while mitigating the risk of knock. One of the most [...] Read more.
The growing demand to reduce emissions of pollutants and CO2 from internal combustion engines has led to a critical need for the development of ultra-lean burn engines that can maintain combustion stability while mitigating the risk of knock. One of the most effective techniques is the pre-chamber spark-ignition (PCSI) system, where the primary combustion within the cylinder is initiated by high-energy reactive gas jets generated by pilot combustion in the pre-chamber. Due to the complex physical and chemical processes involved in PCSI systems, performing 3D CFD simulations is crucial for in-depth analysis and achieving optimal design parameters. Moreover, combining a detailed CFDs model with a calibrated 0D/1D model is expected to provide a wealth of new insights that are difficult to gather through experimental methods alone, making it an indispensable tool for improving the understanding and optimization of these advanced engine systems. In this context, numerous previous studies have utilized CFD models to optimize key design parameters, including the geometric configuration of the pre-chamber, and to study combustion characteristics under various operating conditions in PCSI engines. Recent studies indicate that several advanced models designed for conventional spark-ignition (SI) engines may not accurately predict performance under the demanding conditions of Turbulent Jet Ignition (TJI) systems, particularly when operating in lean mixtures and environments with strong turbulence–chemistry interactions. This review highlights the pivotal role of Computational Fluid Dynamics (CFDs) in optimizing the design of pre-chamber spark-ignition (PCSI) engines. It explores key case studies and examines both the advantages and challenges of utilizing CFDs, not only as a predictive tool but also as a critical component in the design process for improving PCSI engine performance. Full article
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