Browse Topic: Spark ignition engines

Items (4,336)
The aim of the present work was to characterize macroscopic spray parameters of a multi-hole direct injection injector for spark ignition engine applications. The geometry, the position of spray boundaries the overall cone angle, the spray vertical penetration and the vertical spray length were evaluated by processing the spray images recorded at 3300 frames per second. The frequency of recording images was suitable for capturing all the spray developments in all tested conditions. The tested fluid was EXXSOL D60 for simulating ethanol spray characteristics due to its similar properties and due to security reasons. The injector was tested outside the engine and into an open acrylic chamber being injected into atmospheric air conditions of the laboratory. The injection pressure was set up in 100 bar and the simulated engine speed were set up in MOTEC ECU in 3000 rpm, 3600 rpm and 4000 rpm. The injection durations were set up in 3,0 ms for 3000 rpm and 2.3 ms for 3600 rpm and 4000 rpm
Guzzo, Márcio ExpeditoFonseca, Lucas GuimarãesDuarte, Thales Henrique RamosBaeta, José Guilherme CoelhoHuebner, RudolfPujatti, Fabrício José Pacheco
The increasing impacts of the greenhouse effect have driven the need to reduce pollutant emissions from internal combustion engines. Renewable fuels are promising alternatives for emission reduction, and enhancing engine efficiency can further decrease specific emissions. This study explores the development of dual-fuel engines to meet these goals, focusing on dual-fuel combustion in spark-ignition (SI) engines using two different bioethanol and natural gas mixtures. A novel methodology for 1-D predictive combustion simulation in dual-fuel SI engines was developed and implemented in GT-Suite software. The approach involves a straightforward estimation of the laminar flame speed of the fuel mixture and the calibration of turbulent combustion parameters using a genetic optimization algorithm, without the need for complex chemical kinetics models. The results indicate that the proposed methodology can reproduce combustion characteristics, achieving satisfactory outcomes across most tested
Pasa, Giovanni DuarteMartins, ClarissaCota, FilipeDornelles, HenriqueDuarte, ThalesRosalen, RodrigoPujatti, Fabrício José Pacheco
An inwardly-opening pressure swirl injector for direct injection spark ignition engine applications was used in this work for injecting EXXSOL D60 into laboratory gaseous atmospheric conditions into an open chamber. The EXXSOL D60 fluid was used due to its some similar physical properties to Ethanol fuel. Four injection pressures were used in this work: 50 bar, 60 bar, 70 bar and 80 bar and the simulated engine speed was set up in 2000 rpm in all cases using the injector outside the engine. Shadowgraph technique associated to a filming process with a rate of acquisition of 3300 frames per second was used for acquiring the spray images. The spray images were treated running scripts in Matlab software. The scripts were written for this present analysis. The injector used in this work produced hollow cone sprays. With the image treatment performed in Matlab software, the vertical penetration length and the external cone angle were obtained. The main results showed that penetration length
Guzzo, Márcio ExpeditoFonseca, Lucas GuimarãesBaeta, José Guilherme CoelhoFilho, Fernando Antonio RodriguesPujatti, Fabrício José Pacheco
High and ultra-high pressure direct injection (UHPDI) can enhance efficiency gains with flex-fuel engines operating on ethanol, gasoline, or their mixtures. This application aims to increase the engine’s compression ratio (CR), which uses low CR for gasoline due to the knocking phenomenon. This type of technology, involving injection pressures above 1000 bar, permits late fuel injection during the compression phase, preventing auto-ignition and allowing for higher compression ratios. UHPDI generates a highly turbulent spray with significant momentum, improving air-fuel mix preparation, and combustion, resulting in even greater benefits while minimizing particulate matter emissions. This study aims to develop ultra-high-pressure injection systems using gasoline RON95 and hydrated ethanol in a single-cylinder engine with optical access. Experimental tests will be conducted in an optically accessible spark ignition research engine, employing thermodynamic, optical, and emission results
Malheiro de Oliveira, Enrico R.Mendoza, Alexander PenarandaMartelli, Andre LuizDias, Fábio J.Weissinger, Frederico F.dos Santos, Leila RibeiroLacava, Pedro Teixeira
The different energy policies and legislations across the globe, unions, or country wise are the key influencer for evaluation of Transport Industry in both advancement of Technologies and Ecosystem development. Accordingly, European Climate law is focusing to achieve net zero greenhouse (or carbon neutral) gas emissions for EU (European Union) countries by 2050. Similarly in India, National Green Hydrogen Mission (NGHM) by Ministry of New and Renewable Energy (MNRE) is aiming for significant decarbonization and to become market leader in Green Hydrogen Transition. Hydrogen is potential fuel for H2-FCEV (Hydrogen Fuel Cell Electric vehicle) and H2-ICE (Hydrogen -Internal combustion Engine) due to its carbon free molecule and other properties. This review paper is focusing on comprehensive study of different aspects of H2- ICE vehicle. Key study areas are mainly Hydrogen (H2) as fuel, Hydrogen Storage System (HSS), H2-ICEs, Hydrogen storge pressure and H2-ICE vehicle architecture. The
Biswas, SanjoyNaik, Amit KumarKashyap, Krishna
This study meticulously examines the ignition coil (IG), a pivotal component in engine operation, which transforms the low voltage from the battery into the high voltage necessary for spark plug electrode flashover, initiating the combustion cycle. Considering the importance of IG coils in engine operation which has a direct impact on the engine performance. Any failure in the IG coils is judged as a critical failure and encompasses severe repercussions. The paper details an investigation into the issue of ‘White Deposition’ on IG coils. White deposit was observed in IG Coils during new model development in bench level durability test. A comprehensive failure analysis was conducted, employing vibration analysis, thermal analysis, and chemical analysis of the white deposits to ascertain the root cause. Subsequent to identifying the root cause, the study elaborated on hardware design enhancements as a solution. These design changes were rigorously tested on engine benches, confirmed for
Patel, Hardik ManubhaiGupta, VineetChand, SubhashKumar, Nitish
The combustion of hydrogen (H2) as a fuel is attractive due to its zero-carbon nature and combustion-enhancing properties when used to supplement other fuels. However, the challenge of using H2 as a fuel for transportation applications is the difficulty of onboard storage. One solution to this is to crack onboard stored ammonia (NH3) into H2 which can be supplied to the combustion chamber. However, the reforming process is not always 100 % efficient which can lead to the presence of NH3 in the combustion process. The presence of NH3 can influence engine performance, combustion and emissions. Therefore, this experimental study reports the differences in engine performance between H2 and NH3 reformate mixtures (H2/NH3/N2) added to gasoline in a dual-fuel engine setup under both stoichiometric (λ=1.0) and lean-burn (λ>1.0) operating conditions in a spark ignition (SI) engine. In this study, gasoline was used as the main fuel, with the H2 and NH3 reformate blends studied having energy
Yavuz, MustafaWu, MengdaCova-Bonillo, AlexisBrinklow, GeorgeHerreros, JoseTsolakis, Athanasios
For realizing a super-leanburn SI engine with a very-high compression ratio, it is necessary to design a new fuel which could have low ignitability at a low temperature for antiknocking, but high ignitability at a high temperature for some contribution to stable combustion. C2H6 has a very-long ignition delay time at a low temperature, close to that of CH4, but a short ignition delay time at a high temperature, close to that of gasoline. C2H6 also has a laminar burning velocity about 1.2 times higher than that of gasoline. C2H6 addition to gasoline could be a good example of fuel design to improve both combustion stability and antiknocking property. In the present study, the antiknocking effect of adding CH4, C2H6, or C3H8 with the RON of 120, 115, or 112, respectively, to a regular-gasoline surrogate fuel with the RON of 90.8 has been investigated in an SI engine with a stoichiometric mixture. With the energy fraction of the gaseous fuel of less than 0.35, knocking limit CA50 is
Kuwahara, KazunariShimizu, TaiseiOkada, Atsuki
Letter from the Focus Issue Editors
Lakhlani, HardikKumar, VivekWenbin, YuBagga, KalyanGundlapally, SanthoshDi Blasio, GabrieleSplitter, DerekRajendran, Silambarasan
The research for sustainable alternative fuels for combustion engines was driven by the urgency to meet future emission regulation norms and mitigate climate change and dependency on fossil fuels. In this context, methanol emerges as a promising candidate due to its potential for greenhouse gas-neutral production methods and its advantageous characteristics for employment in SI engines. Adverse effects, such as elevated emissions due to incomplete combustion along with liner impingement and oil dilution as a consequence of the high injected fuel mass and the large enthalpy of vaporization, can be improved by a dual injection concept. The tests were conducted on a single-cylinder research engine derived from a common passenger vehicle engine. The exhaust gas composition was measured with an FTIR-analyzer employing a methanol-specific evaluation method, standard exhaust gas analyzers, and a solid particle counter system with 10 and 23 μm cut-off sizes. The ratio of DI mass to total mass
Fitz, PatrickFellner, FelixRößlhuemer, RaphaelHärtl, MartinJaensch, Malte
Hydrogen-powered mobility is believed to be crucial in the future, as hydrogen constitutes a promising solution to make up for the non-programmable character of the renewable energy sources. In this context, the hydrogen-fueled internal combustion engine represents one of the suitable technical solution for the future sustainable mobility. In a short-term perspective, the development of the green hydrogen production capability and distribution infrastructure do not allow a substantial penetration of pure hydrogen IC engines. For this reason, natural gas – hydrogen blends can represent a first significant step towards decarbonization, also determining a trigger effect on the hydrogen market development. The present paper is focused on the analysis of the combustion and performance characteristics of a production PFI natural gas engine, run on blends with 15% in volume of hydrogen (HCNG). More specifically, a fuel-flexible, predictive 1D simulation model has been developed within the
Baratta, MirkoDi Mascio, ValerioMisul, DanielaMarinoni, AndreaCerri, TarcisioOnorati, Angelo
The need to reduce vehicle-related emissions in the great cities has led to a progressive electrification of urban mobility. For this reason, during the last decades, the powertrain adopted for urban buses has been gradually converted from conventional Internal Combustion Engine (ICE), diesel, or Compressed Natural Gas (CNG), to hybrid or pure electric. However, the complete electrification of Heavy-Duty Vehicles (HDVs) in the next years looks to be still challenging therefore, a more viable solution to decarbonize urban transport is the hybrid powertrain. In this context, the paper aims to assess, through numerical simulations, the benefits of a series hybrid-electric powertrain designed for an urban bus, in terms of energy consumption, and pollutants emissions. Particularly a Diesel engine, fueled with pure hydrogen, is considered as a range extender. The work is specifically focused on the design of the Energy Management Strategy (EMS) of the series-hybrid powertrain, by comparing
Nacci, GianlucaCervone, DavideFrasci, EmmanueleLAKSHMANAN, Vinith KumarSciarretta, AntonioArsie, Ivan
Hydrogen engines are currently considered as a viable solution to preserve the internal combustion engine (ICE) as a power unit for vehicle propulsion. In particular, lean-burn gasoline Spark-Ignition (SI) engines have been a major subject of investigation, due to their reduced emission levels and high thermodynamic efficiency. Lean charge is suitable for passenger car applications, where the demand of mid/low power output does not require an excessive amount of air to be delivered by the turbocharging unit, but can difficulty be tailored in the field of high-performance engine, where the air mass delivered would require oversized turbocharging systems or more complex charging solutions. For this reason, the range of feeding conditions near the stochiometric is explored in the field of high-performance engines (20 BMEP), leading to the consequent issue of abatement of pollutant emissions. In this work, a 1D model is applied to the modeling of a four cylinder engine fueled with direct
Marinoni, AndreaMontenegro, GianlucaCerri, TarcisioDella Torre, AugustoOnorati, Angelo
The global push to minimize carbon emissions and the imposition of more rigorous regulations on emissions are driving an increased exploration of cleaner powertrains for transportation. Hydrogen fuel applications in internal combustion engines are gaining prominence due to their zero carbon emissions and favorable combustion characteristics, particularly in terms of thermal efficiency. However, conventional Spark-Ignition (SI) engines are facing challenges in meeting performance expectations while complying with strict pollutant-emission regulations. These challenges arise from the engine's difficulty in handling advanced combustion strategies, such as lean mixtures, attributed to factors like low ignition energy and abnormal combustion events. To address these issues, the Barrier Discharge Igniter (BDI) stands out for its capability to generate non-equilibrium Low-Temperature Plasma (LTP), a strong promoter of ignition through kinetic, thermal, and transport effects. Its surface
Avana, MassimilianoRicci, FedericoPapi, StefanoZembi, JacopoBattistoni, MicheleGrimaldi, Carlo N.
In a context of growing concern for vehicle-related CO2 and pollutant emissions, non-conventional fuels like methanol (CH3OH) represent a valid alternative to fossil fuels to decarbonize the transport sector in a reasonable time. This is mainly due to its lower carbon content than conventional gasoline and diesel. Moreover, methanol can be obtained either from biomass or CO2 capture from the atmosphere, which makes the latter a renewable fuel. Given the possibility of being stored in liquid phase at standard temperature and pressure (STP), methanol is very suitable for Light Duty Vehicles (LDVs), in which the need to contain fuel tank dimensions is relevant. Regarding the deployment of methanol as a fuel, it is not very challenging, as it can be adopted in current production Internal Combustion Engines (ICEs) either in pure form or in blend with other fuels without any significant modifications. Within this context, the present work aims to assess, in both experimental and simulation
Frasci, EmmanueleSementa, PaoloArsie, IvanVaglieco, Bianca Maria
Vibrations in IC engines have a widespread effect on the operations of consumer and commercial vehicles, which not only affect the life and efficiency of the vehicle but also affect user comfort and nervous system of human body. This paper focuses on the comparative analysis of vibration and acoustic characteristics while utilizing fuels such as petrol and CNG. ADXL 335 3-axis accelerometer was employed to measure acceleration vs time data, which was then processed using MATLAB to obtain FFT and PSD plots. These plots thus obtained gave insights on dominating frequency as well as frequencies with maximum energy. Six different cases with different engine speeds and loading conditions are studied with analysis of all the different parameters such as sound pressure levels and mean and max cylinder pressure
Anasune, Aditya
The present study explores the performance of high-density polyethylene (HDPE) pyrooil and ethanol blends with gasoline in SI engine using statistical modeling and analysis using response surface methodology (RSM) and the Anderson–Darling (AD) residual test. The pyrooil was extracted from HDPE through pyrolysis at 450°C and then distilled to separate the liquid fraction. Two blends were prepared by combining pyrooil and gasoline, and pyrooil–ethanol mixture (volume ratio of 9:1) and gasoline, both at volumetric concentrations ranging from 2% to 8% to evaluate brake thermal efficiency (BTE) and specific fuel consumption (SFC) in a SI engine. An experimental matrix containing speed, torque, and blend ratio as independent variables for both blends were designed, analyzed, and optimized using the RSM. The results show that a 4% blend of pyrooil with gasoline (P4) and a 6% blend of pyrooil–ethanol mixture with gasoline (P6E) were optimum for an SI engine. Also, the experimental findings
Manickavelan, K.Sivaganesan, S.Sivamani, S.Kulkarni, Mithun V.
The current research elucidates the application of response surface methodology to optimize the collective impact of methanol–isobutanol–gasoline blends and nanolubricants on the operational parameters of a spark-ignition engine. Diverse alcohol blends in conjunction with gasoline are employed in engine trials at 2500 rpm across varying engine loads. The alcohol blends exhibit notable enhancements in brake thermal efficiency, peak in-cylinder pressure, and heat release rate. At 2500 rpm and 75% load, the break thermal efficiency of iBM15 surpasses that of gasoline by 33.5%. Alcohol blends significantly reduce hydrocarbon and carbon monoxide emissions compared to gasoline. The iBM15 demonstrates a reduction of 25.2% and 51.12% in vibration along the Z and Y axes, respectively, relative to gasoline. As per the response surface methodology analysis, the optimal parameters are identified: an alcohol content of 29.99%, an engine load of 99.06%, and a nanolubricant concentration of 0.1%. It
Bharath , Bhavin KSelvan , V. Arul Mozhi
The article presents the results of simulation studies of pollutant emissions from passenger cars. The characteristics of emissions were determined using the vehicle driving test procedures, in consideration of differentiated average velocities as well as model traffic conditions: urban traffic jam, urban traffic with no congestion, rural, motorways, and highways. This article also presented the possibility of determining the characteristics of pollutant emission based on a singular realization of the vehicle velocities processes, as well as the intensity of pollutant emission, with the use of the Monte Carlo method. The pollutant emission characteristics enable specification of pollutant emission intensity, which can be used for the inventory of pollutant emissions from road transport (COPERT software applied as standard) and can be useful in the assessment of a degree of environmental hazard by modeling pollutant dispersion. In this article, the results related to pollutant emission
Szczepański, KrystianBebkiewicz, KatarzynaChłopek, ZdzisławSar, HubertZakrzewska, Dagna
Nowadays, green hydrogen can play a crucial role in a successful clean energy transition, thus reaching net zero emissions in the transport sector. Moreover, hydrogen exploitation in internal combustion engines is favored by its suitable combustion properties and quasi-zero pollutant emissions. High flame speeds enable a lean combustion approach, which provides high efficiency and reduces NOx emissions. However, high airflow rates are required to achieve the load levels typical of heavy-duty applications. In this framework, the present study aims at investigating the required boosting system of a 6-cylinder, 13-litre heavy-duty spark ignition engine through 1D numerical simulation. A comparison among various architectures of the turbocharging system and the size of each component is presented, thus highlighting the limitations and potentialities of each architecture and providing important insights for the selection of the best turbocharging system
Pucillo, FrancescoMillo, FedericoPiano, AndreaGiordana, SergioRapetto, NicolaPaulicelli, Fabio
Due to its physical and chemical properties, hydrogen is an attractive fuel for internal combustion engines, providing grounds for studies on hydrogen engines. It is common practice to use a mathematical model for basic engine design and an essential part of this is the simulation of the combustion cycle, which is the subject of the work presented here. One of the most widely used models for describing combustion in gasoline and diesel engines is the Wiebe model. However, for cases of hydrogen combustion in DI engines, which are characterized by mixture stratification and in some cases significant incomplete combustion, practically no data can be found in the literature on the application of the Wiebe model. Based on Wiebe’s formulas, a mathematical model of hydrogen combustion has been developed. The model allows making computations for both DI and PFI hydrogen engines. The parameters of the Wiebe model were assessed for three different engines in a total of 26 operating modes. The
Osetrov, OleksandrHaas, Rainer
Dimethyl ether (DME) is an alternative fuel that, blended with propane, could be an excellent alternative for exploring the use of fuels from renewable sources. DME–propane blends are feasible for their comparable physicochemical properties; these fuels may be pressured as liquids using moderate pressure at ambient temperature. Adding a proportion of DME with a low octane number to a less reactive fuel like propane can improve the combustion process. However, the increased reactivity of the mixture induced by the DME could lead to the early appearance of knocking, and this tendency may even be pronounced in boosted SI engines. Hence, this study experimentally analyzes the effect of E10 gasoline (baseline) and DME–propane blends, with varying proportions of DME in propane ranging from 0% to 30% by weight, in increments of 5% on knocking tendency, combustion characteristics, gaseous emissions, and particle number concentration, under different intake pressure conditions (0.8, 0.9, 1.0
Soto, LianHan, TaehoonBoehman, Andre L.
The reduction of anthropogenic greenhouse gas emissions and ever stricter regulations on pollutant emissions in the transport sector require research and development of new, climate-friendly propulsion concepts. The use of renewable hydrogen as a fuel for internal combustion engines promises to provide a good solution especially for commercial vehicles. For optimum efficiency of the combustion process, hydrogen-specific engine components are required, which need to be tested on the test bench and analysed in simulation studies. This paper deals with the simulation-based investigation and optimisation of fuel injection in a 6-cylinder PFI commercial vehicle engine, which has been modified for hydrogen operation starting from a natural gas engine concept. The focus of the study is on a CNG-derived manifold design which has been adapted with regard to the injector interface and is already equipped with so-called gas injection guiding tubes for targeted fuel injection in front of the
Jung, Philipp EmanuelGuenthner, MichaelWalter, Nicolas
Hydrogen engines are currently considered as a viable solution to preserve the internal combustion engine (ICE) as a power unit for vehicle propulsion. In particular, lean-burn gasoline Spark-Ignition (SI) engines have been a major subject of investigations, due to their reduced emission levels and high thermodynamic efficiency. Lean charge is suitable for the purpose of passenger car applications, where the demand of mid/low power output does not require an excessive amount of air to be delivered by the turbocharging unit, but can difficulty be tailored in the field of high performance engine, where the air mass delivered would require oversized turbocharging systems or more complex charging solutions. For this reason, the range of feeding conditions near the stochiometric value is explored in the field of high performance engines, leading to the consequent issue of abatement of pollutant emissions. In this work a 1D model is applied to the modeling of a V8 engine fueled with direct
Montenegro, GianlucaMarinoni, AndreaDella Torre, AugustoD'Errico, GianlucaOnorati, AngeloCerri, Tarcisio
Heavy duty engines for long-haul trucks are quite difficult to electrify, due to the large amount of energy that should be stored on-board to achieve a range comparable to that of conventional fuels. In particular, this paper considers a stock engine with a displacement of 12.9 L, developed by the manufacturer in two different versions. As a standard diesel, the engine is able to deliver about 420 kW at 1800 rpm, whereas in the compressed natural gas configuration the maximum power output is 330 kW, at the same speed. Three possible alternatives to these fossil fuels are considered in this study: biodiesel (HVOlution by Eni), bio-methane and green hydrogen. While the replacement of diesel and compressed natura gas with biofuels does not need significant hardware modifications, the implementation of a hydrogen spark ignition combustion system requires a deep revision of the engine concept. For a more straightforward comparison among the alternative fuels, the same engine platform has
Volza, AntonelloPisapia, AlfredoCaprioli, StefanoRinaldini, CarloMattarelli, Enrico
This work aims at investigating the optimal configuration of an internal combustion engine fueled with bio-ethanol for improving its brake power and efficiency as well as for reducing the NOx emissions, in stationary applications. A turbocharged spark ignition engine characterized by a single-point injection was preliminarily considered; subsequently, a direct injection configuration was investigated. For both cases, a 1-D numerical model was developed to compare the injection configurations under stoichiometric conditions and different spark timings. The analysis shows that the direct injection guarantees: a limited improvement of brake power and efficiency when the same spark timing is adopted, while NOx emissions increases by 20%; an increase of 6% in brake power and 2 percentage points in brake thermal efficiency by adopting the knock limited spark advance, but an almost double NOx emissions increase. In order to exploit the advantages of the direct injection, an engine
Perrone, DiegoFalbo, LuigiFalbo, BiagioCastiglione, Teresa
Low-temperature heat release (LTHR) is of interest for its potential to help control autoignition in advanced compression ignition (ACI) engines and mitigate knock in spark ignition (SI) engines. Previous studies have identified and investigated LTHR in both ACI and SI engines before the main high-temperature heat release (HTHR) event and, more recently, LTHR in isolation has been demonstrated in SI engines by appropriately curating the in-cylinder thermal state during compression and disabling the spark discharge. Ethanol is an increasingly common component of market fuel blends, owing to its renewable sources. In this work, the effect of adding ethanol to iso-octane (2,2,4-trimethylpentane) blends on their LTHR behavior is demonstrated. Tests were run on a motored single-cylinder engine elevated inlet air temperatures and pressures were adjusted to realize LTHR from blends of iso-octane and ethanol without entering the HTHR regime. The blends were tested with inlet temperatures of 40
White, Samuel PhilipBajwa, Abdullah UmairLeach, Felix
The transportation sector’s growing focus on addressing environmental and sustainable energy concerns has led to a pursuit of the decarbonization path. In this context, hydrogen emerges as a promising zero-carbon fuel. The ability of hydrogen fuel to provide reliable performance while reducing environmental impact makes it crucial in the quest for net zero targets. This study compares gasoline and hydrogen combustion in a single-cylinder boosted direct injection (DI) spark ignition engine under various operating conditions. Initially, the engine was run over a wide range of lambda values to determine the optimal operating point for hydrogen and demonstrate lean hydrogen combustion’s benefits over gasoline combustion. Furthermore, a load sweep test was conducted at 2000 rpm, and the performance and emission results were compared between gasoline and optimized hydrogen combustion. An in-depth analysis was conducted by varying fuel injection time and pressure. This enabled us to explore
Mohamed, MohamedBiswal, AbinashWang, XinyanZhao, HuaHarrington, AnthonyHall, Jonathan
A detailed investigation was carried out on the performance, combustion, and emissions of a single-cylinder direct injection hydrogen spark ignition (SI) engine with either a side-mounted direct injection (SDI) or a centrally installed direct injection (CDI) injector. The first part of the study analyzed the performance and emissions characteristics of CDI and SDI engine operations with different injection timings and pressures. This was followed by comparing the engine’s performance and emissions of the CDI and SDI operations at different engine speeds and relative air-to-fuel ratios (lambda) with the optimized injection pressure and timings. Furthermore, the performance and emission attributes of the hydrogen engine with the CDI and SDI setups were conducted at a fixed λ value of 2.75 across a broad spectrum of engine loads. The study’s main outcome demonstrates that both direct injection systems produced near-zero CO2, CO, and HC emissions. Stable engine operations could be achieved
Mohamed, MohamedMirshahi, MiladJiang, ChangzhaoZhao, HuaHarrington, AnthonyHall, Jonathan
The Argon Power Cycle (APC) is a novel zero-emission closed-loop argon recirculating engine cycle which has been developed by Noble Thermodynamics Systems, Inc. It provides a significant gain in indicated thermal efficiency of the reciprocating engine by breathing oxygen and argon rather than air. The use of argon, a monatomic gas, greatly increases the specific heat ratio of the working fluid, resulting in a significantly higher ideal Otto cycle efficiency. This technology delivers a substantial improvement in reciprocating engine performance, maximizing the energy conversion of fuel into useful work. Combined Heat and Power (CHP) operating under the APC represents a promising solution to realize a net-zero-carbon future, providing the thermal energy that hard-to-electrify manufacturing processes need while at the same time delivering clean, dispatchable, and efficient power. Since the working fluid in an APC is synthetic, the concentration of argon, oxygen, fuel, and carbon dioxide
Kim, JoohanScarcelli, RiccardoBeardsell, GuillaumeStrickland, TylerNilsen, ChristopherSierra Aznar, Miguel
The abatement of carbon dioxide and pollutant emissions on motorbike spark-ignition (SI) engines is a challenging task, considering the small size, the low cost and the high power-to-weight ratio required by the market for such powertrain. In this context, the passive pre-chamber (PPC) technology is an attractive solution. The combustion duration can be reduced by igniting the air-fuel mixture inside a small volume connected to the cylinder, unfolding the way to high engine efficiencies without penalization of the peak performance. Moreover, no injectors are needed inside the PPC, guaranteeing a cheap and fast retrofitting of the existing fleet. In this work, a 3D computational fluid dynamics (CFD) investigation is carried out over an experimental configuration of motorbike SI engine, operated at fixed operating conditions with both traditional and PPC configurations. The employed CFD methodology is based on a unique flamelet-based combustion model, regardless the selected ignition
Nodi, AlessandroSforza, LorenzoLucchini, TommasoOnorati, AngeloButtitta, MarcoMarmorini, Luca
Methanol emerges as a compelling renewable fuel for decarbonizing engine applications due to a mature industry with high production capacity, existing distribution infrastructure, low carbon intensity and favorable cost. Methanol’s high flame speed and high autoignition resistance render it particularly well-suited for spark-ignition (SI) engines. Previous research showed a distinct phenomenon, known deflagration-based knock in methanol combustion, whereby knocking combustion was observed albeit without end-gas autoignition. This work studies the implications of deflagration-based knock on noise emissions by investigating the knock intensity and combustion noise at knock-limited operation of methanol in a single-cylinder direct-injection SI engine operated at both stoichiometric and lean (λ = 2.0) conditions. Results are compared against observations from a premium-grade gasoline. Experiments show that methanol’s end-gas autoignition occurs at lean conditions, leading to the typical
Singh, EshanStrickland, TylerAbboud, RamiMacDonald, JamesLee, SangukLopez Pintor, Dario
Amid rising demands for fuel efficiency and emissions reduction, enhancing the thermal efficiency of gasoline engines has become imperative, which requires higher efficiency combustion strategies and integrated optimized design to maximize the work output from fuel. In gasoline engine, both increasing the compression ratio and using lean burn mode improve the ratio of useful work output to the energy input effectively, which resulting in higher thermal efficiency. Although there is limited scope for increasing the compression ratio due to the higher sensitivity to knocking, especially under stoichiometric conditions, reduced sensitivity could be got with leaner mixture fill into cylinder, which can further increase the specific heat ratio and thermal efficiency. However, realizing the efficiency benefits of lean burn in gasoline engines necessitates overcoming critical challenges like ensuring robust ignition process and accelerating burning rates to achieve short, stable combustion
Du, JiakunQi, HongzhongChen, HongLi, YuhuaiZhan, WenfengJiang, XiaoxiaoWu, WeilongZhang, Zonglan
When an SI engine is equipped with individual cylinder pressure transducers, combustion timing of each cylinder can be precisely controlled by adjusting spark timing in real-time. In this paper, a novel method based on principal component analysis (PCA) is introduced to control the combustion timing with a significantly less computational burden than a conventional method
Kang, Jun-MoLin, Hejie
Engine knock is one of the limiting factors in determining the compression ratio and engine efficiency for spark ignited engines. Using the Southwest Research Institute Knock-CoV test method, it was previously shown that the knock limited load versus combustion phasing (CA50) has a constant slope. All of the knock mitigation strategies tested provided a shift to these knock limited loads but also increased the slope. That is, for the same CA50 retard the knock limited load could be increased more. Our hypothesis was that due to fuel sensitivity, or the difference between the RON and MON, the reactions that lead to knock will behave differently as the pressure-temperature history changes with engine speeds and loads. The fuel affects on the knock and CoV limits were studied by testing fuels with various sensitivities including methanol, E85 (85% ethanol) and Iso-octane. Methanol and E85 have higher sensitivities compared to the baseline gasoline fuel and as a result showed a steeper
Mitchell, RobertConway, GrahamWang, Yanyu
Substantial effort has been devoted to utilizing homogeneous charge compression ignition (HCCI) to improve thermal efficiency and reduce emission pollutants in internal combustion engines. However, the uncertainty of ignition timing and limited operational range restrict further adoption for the industry. Using the spark-assisted compression ignition (SACI) technique has the advantage of using a spark event to control the combustion process. This study employs a rapid compression machine to characterize the ignition and combustion process of Dimethyl ether (DME) under engine-like background temperature and pressures and combustion regimes, including HCCI, SACI, and knocking onsite. The spark ignition timing was swept to ignite the mixture under various thermodynamic conditions. This investigation demonstrates the presence of four distinct combustion regimes, including detonation, strong end-gas autoignition, mild end-gas autoignition, and HCCI. The observation indicates that HCCI
Jin, LongYu, XiaoWang, MeipingReader, GrahamZheng, Ming
Net-Zero emission ambitions coupled with availability of oxygenated fuels like ethanol encouraged the Government towards commercial implementation of fuels like E20. In this background, a study was taken up to assess the impact of alcohol blended fuels on performance and emission characteristics of a BS-VI complaint motorbike. A single cylinder, 113-cc spark ignition, ECU based electronic fuel injection motorbike was used for conducting tests. Pure gasoline (E0), 10% ethanol-gasoline (E10), 20% ethanol-gasoline (E20) and 15% methanol-gasoline (M15) blends meeting respective IS standards were used as test fuels. The oxygen content of E10, E20 and M15 fuels were 3.7%, 7.4% and 8.35% by weight respectively. Experiments were conducted following worldwide motorcycle test cycle (WMTC) as per AIS 137 standard and wide-open-throttle (WOT) test cycle, using chassis dynamometer. The experimental results on WMTC tests indicated that the fuel consumption of the vehicle increased with increase in
Sahu, YamanP, SakthivelSithananthan, MMaheshwari, Mukul
Methanol is one of the most promising fuels for the decarbonization of the off-road and transportation sectors. Although methanol is typically seen as an alternative fuel for spark ignition engines, mixing-controlled compression ignition (MCCI) combustion is typically preferred in most off-road and medium-and heavy-duty applications due to its high reliability, durability and high-efficiency. In this paper, the potential of using ignition enhancers to enable methanol MCCI combustion was investigated. Methanol was blended with 2-ethylhexyl nitrate (EHN) and experiments were performed in a single-cylinder production-like diesel research engine, which has a displacement volume of 0.83 L and compression ratio of 16:1. The effect of EHN has been evaluated with three different levels (3%vol, 5%vol, and 7%vol) under low- and part-load conditions. The injection timing has been swept to find the stable injection window for each EHN level and load. With the highest EHN level, better combustion
Lee, SangukLopez Pintor, DarioCho, Seokwon
In recent months, the increasing debate within the European Union to review the ban on internal combustion engines has led to the pursuit of environmentally neutral solutions for ICEs, as an attempt to promote greater economic and social sustainability. Interest in internal combustion engines remains strong to uphold the principle of technological neutrality. In this perspective, the present paper proposes a numerical methodology for 3D-CFD in-cylinder simulations of hydrogen-fueled internal combustion engines. The combustion modelling relies on G-equation formulation, along with Damköhler and Verhelst turbulent and laminar flame speeds, respectively. Numerical simulations are validated with in-cylinder pressure traces and images of chemiluminescent hydrogen flames captured through the piston of a single-cylinder optical spark-ignition engine. To mitigate the uncertainties related to the modeling of mixture stratification and injection, hydrogen is port-injected and continuously
Sfriso, StefanoBerni, FabioBreda, SebastianoFontanesi, StefanoRamalho Leite, CaioBrequigny, PierreFoucher, Fabrice
The environmental and sustainable energy concerns in transport are being addressed through the decarbonisation path and the potential of hydrogen as a zero-carbon alternative fuel. Using hydrogen to replace fossil fuels in various internal combustion engines shows promise in enhancing efficiency and achieving carbon-neutral outcomes. This study presents an experimental investigation of hydrogen (H2) combustion and engine performance in a boosted spark ignition (SI) engine. The H2 engine incorporates both port fuel injection (PFI) and direct injection (DI) hydrogen fuel systems, capable of injecting hydrogen at pressures of up to 4000 kPa in the DI system and 1000 kPa in the PFI operations. This setup enables a direct comparison of the performance and emissions of the PFI and DI operations. The study involves varying the relative air-to-hydrogen ratio (λ) at different speeds to explore combustion and engine limits for categorising and optimising operational regions. Furthermore, load
Mohamed, MohamedLongo, KevinZhao, HuaHall, JonathanHarrington, Anthony
This work represents an advanced engineering research project partially funded by the U.S. Department of Energy (DOE). Ford Motor Company, FEV North America, and Oak Ridge National Laboratory collaborated to develop a next generation boosted spark ignited engine concept. The project goals, specified by the DOE, were 23% improved fuel economy and 15% reduced weight relative to a 2015 or newer light-duty vehicle. The fuel economy goal was achieved by designing an engine incorporating high geometric compression ratio, high dilution tolerance, low pumping work, and low friction. The increased tendency for knock with high compression ratio was addressed using early intake valve closing (EIVC), cooled exhaust gas recirculation (EGR), an active pre-chamber ignition system, and careful management of the fresh charge temperature. Engine weight reduction measures were implemented throughout the engine system making use of composite materials, advanced manufacturing techniques, and architectural
Shelby, Michael H.Case, Mark E.Chesney, Lynn A.
Engine knock is a major challenge that limits the achievement of higher engine efficiency by increasing the compression ratio of the engine. To address this issue, using a higher octane number fuel can be a potential solution to reduce or eliminate the propensity for knock and so obtain better engine performance. Methanol, a promising alternative fuel, can be produced from conventional and non-conventional energy resources, which can help reduce pollutant emissions. Methanol has a higher octane number than typically gasolines, which makes it a viable option for reducing knock intensity. This study compared the combustion characteristics of gasoline and methanol fuels in an optical spark-ignition engine using multiple spark plugs. The experiment was carried out on a single-cylinder four-stroke optical engine. The researchers used a customized metal liner with four circumferential spark plugs to generate multiple flame kernels inside the combustion chamber. The results indicated that
Uddeen, KalimTang, QinglongShi, HaoAlmatrafi, FahadMagnotti, GaetanoTurner, James
Ammonia (NH3), a zero-carbon fuel, has great potential for internal combustion engine development. However, its high ignition energy, low laminar burning velocity, narrow range of flammability limits, and high latent heat of vaporization are not conducive for engine application. This paper numerically investigates the feasibility of utilizing ammonia in a heavy-duty diesel engine, specifically through low-pressure direct injection (LP-DI) of hydrogen to ignite ammonia combustion. Due to the lack of a well-corresponding mechanism for the operating conditions of ammonia-hydrogen engines, this study serves only as a trend-oriented prediction. The paper compares the engine's combustion and emission performance by optimizing four critical parameters: excess air ratio, hydrogen energy ratio, ignition timing, and hydrogen injection timing. The results reveal that excessively high hydrogen energy ratios lead to an advanced combustion phase, reducing indicated thermal efficiency. Additionally
Xu, XiaotingWang, WeiQi, YunliangWang, ZhiMin, HaijiaoLi, FangweiYin, YongLi, Zhi
In order to improve the fuel economy for future high-efficiency spark ignition engines, the applications of advanced combustion strategies are considered to be beneficial with an overall lean and/or exhaust gas recirculation diluted cylinder charge. Stronger and more reliable ignition sources become more favorable under extreme lean/EGR conditions. Existing research indicates that the frequency of plasma restrikes increases with increased flow velocity and decreased discharge current level, and a higher discharge current can reduce the gap resistance and maintain the stretched plasma for a longer duration under flow conditions. An in-house developed current boost control system provides flexible control of the discharge current level and discharge duration. The current boost ignition system is based on a multi-coil system with a discharge current level of 180mA. In this study, a comparative study has been conducted to investigate the efficacy of multi-coil and multi-core ignition
Yu, XiaoLeblanc, SimonWang, LinyanZheng, MingTjong, Jimi
Due to increasingly strict emission regulations, the demand for internal combustion engine performance has enhanced. Combustion stability is one of the main research focuses due to its impacts on the emission level. Moreover, the combustion instability becomes more significant under the lean combustion concept, which is an essential direction of internal combustion engine development. The combustion instability is represented as the cycle-to-cycle variation. This paper presents a quasi-dimensional model system for predicting the cycle-to-cycle variation in 0D/1D simulation. The modeling is based on the cause-and-effect chain of cycle-to-cycle variation of spark ignition engines, which is established through the flow field analysis of large eddy simulation results [1]. In the model system, varying parameters are turbulent kinetic energy, the distribution of air-to-fuel equivalence ratio, and the in-cylinder velocity field. The model system considers both the global and the local
Feng, YeMirsch, NiklasMir, Daniel IsmailKulzer, André CasalGrill, MichaelSteeger, FabianBlomberg, MichaelPischinger, Stefan
Alternative fuels, such as natural and bio-gas, are attractive options for reducing greenhouse gas emissions from combustion engines. However, the naturally occurring variation in gas composition poses a challenge and may significantly impact engine performance. The gas composition affects fundamental fuel properties such as flame propagation speed and heat release rate. Deviations from the gas composition for which the engine was calibrated result in changes in the combustion phase, reducing engine efficiency and increasing fuel consumption and emissions. However, the efficiency loss can be limited by estimating the combustion phase and adapting the spark timing, which could be implemented favorably using a closed-loop control approach. In this paper, we evaluate the efficiency loss resulting from varying gas compositions and the benefits of using a closed-loop controller to adapt the spark timing to retain the nominal combustion phase. We use a 13-liter natural gas-fueled heavy-duty
Björnsson, OlaTunestal, Per
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