Browse Topic: Ignition systems

Items (2,084)
Find
A Comparative Study of Evaluation Indicators in Spark Plug Electrode Erosion Resistance Using High Energy Ignition2026-01-0291To be published on 04/07/2026
Lean combustion is one of the effective methods to improve the efficiency of engine. High energy ignition can significantly enhance the stability of lean combustion, attracting widespread attention in engine applications, particularly in GDI engines. However, higher ignition energy accelerates the erosion rate of spark plug electrodes, thereby shortening their lifespan. Currently, there is no established quantitative evaluation method for assessing the erosion resistance of spark plug electrodes with a high energy ignition system. Thus, developing a reliable and rapid testing method to evaluate the erosion resistance of spark plug electrode materials is crucial and urgent. Such a method would facilitate the selection of superior electrode materials, ultimately improving the erosion resistance of spark plugs and extending their lifespan. This study developed an innovative erosion testing system for spark plug center electrode materials based on a self-made high energy ignition device
Zhang, Jianqi, Sun, Nan, Miao, Xinke, Li, Yang, Zhou, Chuan, Deng, Jun, Li, Liguang
Investigation of In-Cylinder Cycle-to-Cycle Variation Using PIV, LIF and RANS Simulation2026-01-0299To be published on 04/07/2026
To elucidate the cycle-to-cycle variations (CCV) in gas flow and combustion within gasoline engine cylinders, simultaneous two-section PIV and LIF measurements were performed using an optical engine, coupled with RANS simulations. The results revealed the following: The variation in the equivalence ratio per cycle has little effect on initial combustion but does influence IMEP. Evaluating the laminar combustion velocity (SL) and turbulent combustion velocity (ST) as factors determining initial combustion revealed almost no correlation with SL, while moderate correlations were observed between ST and CA10. The position of the tumble vortex center at ignition timing was found to be critical; the vortex center position most favorable for advancing combustion timing was located to the right and below the spark plug. Under nitrogen-enriched conditions with a dilution ratio of approximately 40%, cycle fluctuations increased. Concentration characteristics of THC and CO, obtained from high
Hokimoto, Satoshi, Moriyoshi, Yasuo, Kuboyama, Tatsuya
A Comparative Study of Combustion Stability Improvement via Prolonged Discharge Duration under Engine Idling Conditions2026-01-0308To be published on 04/07/2026
Proper control over combustion and emission characteristics under engine idling conditions remains to be challenging, especially when engine block temperature is low. In previous publication from the author’s laboratory, a specially designed common-coil pack was demonstrated to improve engine idling performance by supplying prolonged ignition duration and elevated discharge current amplitude. In this paper, the progress on further development of the ignition system was reported with improved system stability and enhanced ignition performances. The impact of discharge current amplitude and discharge duration on the combustion stability was investigated in detail under a wide range of spark timings, aiming to eliminate misfire events and reduce engine-out emissions under engine block temperature of 30°C. Such improvement can help to reduce the HC and CO emissions during engine cold start process before the light up of the three-way catalyst, therefore, reduce the total emissions of a
Yu, Xiao, Zheng, Ming, Jin, Long, Leblanc, Simon
Investigation of Flame Speed Effects Towards Knock Suppression in a Boosted Spark-Ignited Engine Using 1-D Modeling2026-01-0311To be published on 04/07/2026
To combine high efficiencies and low pollutant emissions, engine manufacturers have developed downsized spark-ignited (SI) engines in light- and medium-duty applications utilizing charge boosting and high compression ratio. While these techniques have proven effective, abnormal combustion such as auto-ignition and knock present a challenge and an important limitation towards high efficiencies. In this work, simulations have been utilized for knock onset predictions as well to provide relevant insights and trends of engine and fuel parameters including flame speed on auto-ignition. A one-dimensional (1-D) GT-Power model was utilized in this study with a semi-predictive flame propagation model and kinetic mechanism solver to isolate the flame propagation rate on auto-ignition and knock. This work presents a comprehensive study of the laminar flame speed (LFS) effect on combustion at knocking conditions in a high compression ratio long stroke engine (LSE) fueled by propane. Knock onset
Douvry-Rabjeau, Julien, DelVescovo, Dan
Effects of methane addition to diesel in dual-fuel mode combustion in AFIDA2026-01-0344To be published on 04/07/2026
With the rising pressure of a global energy transition to cleaner energy systems, the transportation sector faces a challenge in maintaining its current structure and adapting to all the required changes. Dual-fuel technology emerges as a promising alternative to keep the viability of the sector while utilizing environmentally friendly fuels alongside traditional hydrocarbons, without deep structural changes in the current framework. This work investigates the impact of the use of methane gas coupled with diesel fuel, specially focusing its influence on the ignition delay time (IDT) in a dual-fuel combustion setting. The investigation employed the Advanced Fuel Ignition Delay Analyzer (AFIDA), a constant-volume combustion chamber capable of automated measuring of multiple samples in a single run. Methane gas was introduced into the chamber at molar concentrations of 1%, 2% and 3% and at initial pressures of 5 and 10 bar, with temperature values ranging from 653 to 723 K. With the same
Virginio, Thiago, Eraqi, Basem, Sakleshpur Nagaraja, Shashank, Sarathy, Mani
Relative Knocking Intensity to Discuss Similarities and Differences between Low- and High-Speed Knocking Phenomena2026-01-0312To be published on 04/07/2026
Knocking intensity, the maximum half-amplitude of pressure oscillation, reaches 1 MPa once in thousands of cycles under a certain boosted high-load condition with a spark-ignition timing advanced to excess at the engine speed of 5000 rpm, which is named high-speed super knocking. In the present study, a mass-production turbo-charged direct-injection gasoline engine is operated for the indicated mean effective pressure of 1.7 MPa at the engine speed of 1500 to 5000 rpm. Unburned-zone autoignition timing is estimated using Livengood-Wu integral coupled with a small set of ignition delay time equations developed by one of the authors, which has a difference below 2 degrees from that detected from the differential value of net heat release rate. Whenever autoignition occurs at 15 degrees after TDC, ignition delay time in the unburned zone is the period of about 10 degrees at the autoignition timing, regardless of engine speed. Knocking intensities with a spark-ignition timing advanced to
Zeng, Changzhi, Kuboyama, Tatsuya, Yatsufusa, Tomoaki, Okuyama, Shota, Kuwahara, Kazunari
Investigation of CDI and TCI Ignition Charactertistics for Lean Hydrogen–Air Mixtures in a Constant Volume Combustion Chamber2026-01-0327To be published on 04/07/2026
The discharge characteristics of ignition systems strongly influence the formation of flame kernels under lean-burn conditions. In this study, two ignition strategies are compared. A capacitor discharge ignition (CDI) system characterized by discharge energy of 1–5 mJ with discharge current around 300 mA and short discharge duration (~50 μs). A transistor coil ignition (TCI) system delivering discharge energy of 30–50 mJ with lower discharge current (~100 mA) and millisecond-scale discharge duration. These two systems represent distinct discharge current profiles, namely “high-current/short-duration” and “low-current/long-duration.” The influence of discharge current profile on flame kernel formation and early flame development in lean hydrogen–air mixtures is investigated. Experiments are conducted in a constant-volume combustion chamber with hydrogen–air mixtures at various global equivalence ratios. Both quiescent and flow conditions are considered. High speed shadowgraph imaging is
Cong, Binghao, Jin, Long, Yu, Xiao, Zheng, Ming
Emission and Combustion Characteristics of a Hydrogen Direct-Injection Spark Ignition Engine using EGR2026-01-0325To be published on 04/07/2026
Hydrogen is recognized as a promising alternative fuel for internal combustion engines as it contains no carbon, but in addition to NOx emissions during hydrogen combustion, unburned hydrogen emissions have recently emerged as an important environmental issue. In this study, a 400 cc single-cylinder direct-injection hydrogen engine based on a 1.6 L Hyundai Kappa engine was used to analyze the effects of injection and ignition timing on combustion characteristics and engine emissions. Experimental results showed that the formation state of the air-fuel mixture varied with injection and ignition timing. Under conditions where locally fuel-rich mixtures were formed, NOx emissions increased while unburned hydrogen decreased. In contrast, when the mixture was relatively homogeneous, NOx decreased but unburned hydrogen increased. These findings clearly confirmed the trade-off relationship between NOx and unburned hydrogen emissions. To address this issue, exhaust gas recirculation (EGR) was
Yang, Heetae, Ki, Youngmin, Kim, Jungho Justin, Kim, Jinsu
Effect of Ignition Timing on Combustion Performance in Ammonia-Hydrogen Blended Fuel Engine2026-01-0323To be published on 04/07/2026
Against the backdrop of energy structure transformation and upgraded environmental protection requirements, ammonia has been significantly attracted for its potential application as a zero-carbon fuel. However, it faces challenges such as difficult ignition, slow combustion rate, and low heating value. Thus, researching efficient combustion strategies suitable for ammonia as a fuel holds great significance. In this study, a two-cylinder diesel engine was modified into an ammonia-hydrogen blended fuel engine, experimental and simulation studies were carried out to investigate the effects of varying ignition timing on the combustion performance employed a passive pre-chamber ammonia-hydrogen fuel engine. The results show that the peak in-cylinder pressure exhibits a "first increase then decrease" trend as the ignition timing is retarded, reaching a maximum value of 7.42 MPa at the ignition timing of -27.5°CA ATDC. When the ignition timing is retarded beyond -15°CA ATDC, a double-peak
Deng, Jun, Luo, Mingyu, Shang, Quanbo, Tang, Yongjian, Qin, Jie, Li, Liguang
EGR Tolerance of Synthetic Gasoline Fuels in a DISI Engine: Fuel Effects on Performance and Emissions2026-01-0305To be published on 04/07/2026
Drop-in synthetic gasoline fuels are an attractive alternative to traditional fossil fuels for transportation due to their high energy density, compatibility with the existing fleet and potential to decrease carbon intensity. Despite of meeting gasoline standards, the composition of these fuels can vary depending on the feedstock used for production and production process, which has shown to affect engine performance and emissions. This study investigated the effects of synthetic fuel composition on combustion in a direct-injection spark-ignition engine. Spark timing sweeps from the stability limit to the knock limit were performed with three different bio-fuels, methanol-to-gasoline, ethanol-to-gasoline and hydrotreated-biomass gasoline, at different loads, speeds and exhaust gas recirculation (EGR) rates, and results were compared against a research-grade E10 (10%vol ethanol) regular gasoline representative of petroleum gasoline available in the US. Octane index analyses showed that
MacDonald, James, Narayanan, Abhinandhan, Lopez Pintor, Dario, Matsubara, Naoyoshi, Kitano, Koji, Yamada, Ryota, Sugata, Kenji
Optimizing an H2 combustion system and investigating abnormal combustions through advanced visualization techniques2026-01-0324To be published on 04/07/2026
The rapidly evolving mobility sector is facing the dual challenge of market expansion and the need for significant emissions reduction. Most of the transition tends to go in favor of electrification, yet it’s widely assumed that no single solution is perfect. Thus, hydrogen as an energy-vector presents a compelling alternative. H2 internal combustion engine use a well-known architecture and utilizes existing production facilities making it a viable short-term and cost-effective option. This context prompted us to investigate the hydrogen spark-ignited internal combustion engine, focusing specifically on critical combustion issues. Various studies have identified recurring challenges such as managing abnormal combustion and achieving high specific power. During our in-house developments, we also faced abnormal combustions and sought to determine the root cause of these issues. Initially, using a modular single-cylinder engine, a combustion system has been optimized regarding injection
LONDOS, Benoit, Bardi, Michele, Serrano, David, Laget, Olivier, Gautrot, Xavier, Bramoullé, Clément, Cordier, Matthieu
Flame Velocity and Combustion Behaviour of Ammonia–Hydrogen Blends: A Combined Experimental and Numerical Study2026-01-0320To be published on 04/07/2026
Ammonia is gaining importance as a viable energy vector for decarbonising the maritime sector. However, ammonia flame speed is much slower than that of traditional fuels, and this can result in incomplete burning, decreased engine efficiency, and increased undesirable emissions such as unburned ammonia (NH₃). While blending hydrogen with ammonia has been shown to mitigate some of ammonia's combustion drawbacks, the underlying mechanisms driving these improvements are still not fully understood. This study explores these processes to inform better optimisation. A 1.2 L optically accessible constant volume combustion chamber equipped with a wall-mounted surface spark plug was used to investigate the combustion characteristics and apparent flame velocity of ammonia-hydrogen blends. Chamber pressure and temperature were measured using high-frequency piezoresistive pressure transducers and K-type thermocouples. Flame propagation was captured at 9,000 frames per second using a Photron
Bodur, Tuna Murat, Bowling, William, La Rocca, Antonino, Cairns, Alasdair
Effect of Pre-Chamber Geometry on Methanol Cold-Start Combustion in an SI Engine2026-01-0307To be published on 04/07/2026
Vehicle pollutant emissions represent a key issue in the development of internal combustion engines. In recent decades, the automotive industry has been driven to explore innovative solutions, such as the use of alternative fuels and lean-burn combustion strategies, in order to meet increasingly stringent emission regulations. In this context, pre-chamber ignition systems show strong potential for reducing both fuel consumption and emissions, due to their ability to operate under lean mixtures and with non-conventional fuels. The aim of this work is to investigate the evolution of plasma jets under different in-cylinder combustion conditions, using methanol as fuel and integrating a pre-chamber heating system to improve cold-start operation. The experimental activity was carried out on a small optical spark-ignition (SI) engine, alternatively equipped with a conventional ignition system and a pre-chamber. The engine was operated at 2000 rpm under wide open throttle (WOT) in standard
Sementa, Paolo, Altieri, Nunzio, Tornatore, Cinzia
Experimental Study on the effect of Ignition Strategy on Combustion and Emissions in a Direct Injection Hydrogen Engine2026-01-0330To be published on 04/07/2026
Hydrogen-fueled internal combustion engines (H₂ICEs) are a promising pathway toward carbon-neutral transportation, but their efficiency and emissions performance are highly sensitive to ignition control strategies. This study systematically investigates the combined effects of spark timing (−10 to −26 °CA bTDC) and spark energy (25–40 mJ) on combustion characteristics in a port fuel-injected H₂ICE operating at a constant speed of 1400 r/min under low, medium, and high load conditions. Results show that spark timing advance produces load-dependent effects: at low load, it increases the peak heat release rate while delaying peak pressure and shortening combustion duration; at medium and high loads, it advances both peaks toward TDC with an optimal spark timing shifting closer to −14 °CA. Ignition delay was only slightly reduced at low load but significantly shortened—by about 3 °CA—at high load. NOₓ emissions increased nearly linearly with spark advance, while slight retardation
ZHAO, KEQIN, Lou, Diming, zhang, yunhua, Fang, Liang, Tan, Piqiang, Hu, Zhiyuan
Development and Trial of a Non-Dominated Sorting Genetic Algorithm for Rapid Engine Calibration2026-01-0285To be published on 04/07/2026
In the quickly changing automotive powertrain landscape, calibration processes are a major bottleneck to production and new technology development. The implementation of rapid powertrain calibration processes can reduce development resource requirements, improve performance, and reduce risk. In previous works the author successfully developed an internal combustion engine calibration strategy using a Lagrange-Multiplier genetic algorithm for multi-constraint optimization. In the present work, this previous algorithm is expanded to create and demonstrate a new non-dominated sorting genetic algorithm which is aimed at identifying the entire Pareto front of the relationship between two engine performance parameters. Accurate and rapid identification of Pareto fronts enables designers to effectively and efficiently balance performance tradeoffs and identify optimal calibration settings. The algorithm developed here optimized the calibration of three combustion control parameters
Mansfield, Andrew
Effect of Ignition Energy on Combustion Duration under Flow Conditions2026-01-0336To be published on 04/07/2026
Utilizing low carbon fuel in lean burn combustion presents a compelling strategy for improving thermal efficiency and reducing NOx emissions. Methane, the main content of natural gas, still receives challenge of a rapid and complete combustion process because of its low chemical reactivity. Further increase of excess air ratio would decrease the flame propagation speed significantly, leading to prolonged combustion durations. The long combustion duration deteriorates the performance of a spark ignition engine, in terms of poor combustion instability and misfire. Although ignition timing can be utilized to adjust the combustion phasing, the ignition process faces challenges due to reduced background pressure and temperature at advanced spark timings. In this paper, a rapid compression machine equipped with a specially designed combustion flow chamber is utilized to enhance the mean flow speed across the spark gap under the background pressure 6 bar abs. and temperature 600 K. A
Jin, Long, Yu, Xiao, Reader, Graham, Zheng, Ming
Characterisation of Particle Number and Size from a DI SI Engine Operating on Hydrogen: Operating Sensitivities and Filtration Effects2026-01-0378To be published on 04/07/2026
Hydrogen Internal Combustion Engines (H₂ICEs) offer the potential for near-zero carbon emissions. However, while nitrogen oxide (NOₓ) emissions have been extensively studied, particle number (PN) emissions, primarily resulting from lubricant oil pyrolysis due to hydrogen’s short quench distance, remain less well understood. This study investigates exhaust particle characteristics from a spark-ignition, single-cylinder research engine, based on MAHLE Powertrain’s downsizing engine combustion system, at Brunel University, London. It compares gasoline and hydrogen direct-injection strategies (central vs. side injection) across a wide range of operating conditions, including variations in engine speed, load, air-fuel ratio (λ), rail pressure, and spark timing. PN and particle size distribution were measured using Cambustion’s DMS500, paired with a catalytic stripper to isolate solid particles. To assess the impact of engine wear, tests were conducted on both a worn engine configuration
Harrington, Anthony, Zaman, Zayne, Nickolaus, Chris, Zhao, Hua, Wang, Xinyan, Hall, Jonathan
Potential for Total Cost of Ownership Reduction using Passive Pre-Chamber Ignition in Natural Gas Engines2026-01-0309To be published on 04/07/2026
Spark plug durability is a factor affecting the total cost of ownership (TCO) of spark-ignited natural gas engines, with some heavy-duty platforms requiring plug replacement after only 750 hours of operation. The high ignition energy demand under lean or diluted conditions accelerates electrode wear, shortening plug life and increasing maintenance frequency. This work evaluates passive pre-chamber (PC) ignition operating at lowered spark energies as a strategy to reduce spark energy requirements and extend plug durability, thereby lowering TCO. Experiments were conducted on a medium-duty Cummins 6.7L ISB engine at 1600 RPM and 50% load under varying exhaust gas recirculation (EGR) dilution levels (0–40%). Two passive pre-chambers, with 1.1 mm and 1.6 mm nozzle diameters, were compared against conventional spark ignition (SI). SI was operated with a fixed coil dwell of 4 ms (~90 mJ), while the PC configuration was tested across 2–4 ms dwell times (~30–90 mJ). Cylinder pressure analysis
Dhotre, Akash, Voris, Alex, Okey, Nathan, Kane, Seamus, Rajasegar, Rajavasanth, Northrop, William
Effects of the Spark Location and Timing in a Heavy-Duty Hydrogen-Fueled Engine2026-01-0331To be published on 04/07/2026
The use of hydrogen in internal combustion engines offers a promising route to low-carbon propulsion in heavy-duty transportation. However, its distinct combustion characteristics as high flame speed, wide flammability limits, and susceptibility to abnormal combustion, necessitate careful engine and ignition system design. This study investigates the combined influence of spark plug location and ignition timing on the performance of a heavy-duty Volvo Diesel engine modified to operate in a spark-ignited mode with hydrogen fuel at low compression ratio under different load conditions. Three-dimensional computational fluid dynamics simulations with detailed hydrogen chemistry, including diffusive-thermal effects, were conducted to evaluate flame development, combustion efficiency, and heat release under different loads. Model validation against combustion behavior and jet characteristics from a low-pressure, high-mass-flow direct injector is also presented. The results demonstrate that
Menaca, Rafael, Shakeel, Mohammad Raghib, Panithasan, Mebin, Liu, Xinlei, Qahtani, Yasser, AlRamadan, Abdullah, Cenker, Emre, Silva, Mickael, Pei, Yuanjiang, Turner, James, Im, Hong
The impact of various renewable hydrocarbons on performance and emissions in a super lean burn engine2026-01-0306To be published on 04/07/2026
Biofuels can play a key role as carbon-neutral transitional energy sources for ICE vehicles as the fleet moves towards increasing electrification. Blending of ethanol plays a key role in enhancing the anti-knock properties of the fuel and also allows renewable hydrocarbons (such as bio-naphtha) to be incorporated into the blend whilst maintaining an acceptable overall fuel quality. Super lean burn ICE technology with λ between 2 and 3 can lead to significantly enhanced fuel economy and reduced NOx emissions. The Toyota prototype engine used to generate data for this project injects most of the fuel in a PFI mode to generate a homogeneous super-lean charge in the cylinder, but just before spark ignition the DI injector sprays a small amount of fuel towards the spark plug to create a richer charge near the spark plug to promote flame kernel development. Various fuel formulations with a high biofuel content were tested in both conventional and super lean burn engines. Certain fuel
Aradi, Allen, Krueger-Venus, Jens, Jain, Sandeep Kumar, Cracknell, Roger, Kolbeck, Andreas, Shibuya, Masahiko, Yamada, Ryota, Matsubara, Naoyoshi, Kitano, Koji
Performance Optimization of 2 Cylinder Flex Fuel Engine for Small Commercial Vehicle – A STEP TOWARDS SUSTAINABILITY2026-26-01191/16/2026
Increasing ethanol blending in gasoline is significant from both financial (reducing dependency on crude oil) and sustainability (overall CO2 reduction) points of view. Flex Fuel is an ethanol-gasoline blend containing ethanol ranging from 20% to 85%. Flex Fuel emerges as an exceptionally advantageous solution, adeptly addressing the shortcomings associated with both gasoline and ethanol. Performance optimization of Flex Fuel is a major challenge as fuel properties like knocking tendency, calorific value, vapour pressure, latent heat, and stoichiometric air-fuel ratio change with varying ethanol content. This paper elaborates on the experimental results of trials conducted for optimizing engine performance with Flex Fuel for a 2-cylinder engine used in a small commercial vehicle. To derive maximum benefit from the higher octane rating of E85, the compression ratio is increased, while ignition timing is optimized to avoid knocking with E20 fuel. For intermediate blends, ignition timing
Kulkarni, Deepak, Malekar, Hemant A, Upadhyay, Rajdip, Katkar, Santosh, Undre, Shrikant
Technologies and Strategies for High Brake Thermal Efficiency Gasoline Engine to Meet the Future CO 2 Emission Targets in India2026-26-00721/16/2026
The Indian automobile industry is experiencing a significant shift, propelled by environmental necessities and national climate obligations set at the CoP26 summit, aiming for a 45% decrease in CO₂ emissions by 2030 and reaching carbon neutrality by 2070 [1]. Transportation continues to be a significant source of air pollution; consequently, India is enhancing its regulatory frameworks with BS VI Stage 2 regulations, CAFE Phase III norms set for 2027, and CAFE Phase IV by 2032 [2]. Furthermore, the transition from MIDC to WLTP driving cycle is meant to increase the accuracy of the efficiency and emissions assessments [2]. To comply to these upcoming regulations, the automotive industry is moving toward producing high efficiency engines in India. A naturally aspirated (NA) 1.5L, 4-cylinder inline gasoline engine was selected from Indian market for this study. Maximum Brake Thermal Efficiency (BTE) of this engine is around 37%. Assessment of new technologies were performed by
Garg, Shivam, Fischer, Marcus, Emran, Ashraf, Jagodzinski, Bartosch, Franzke, Bjoern
Effect of E20 Fuel on Vehicle Performance Parameters of 694CC Gasoline Engine for Commercial Vehicle Application2026-26-05651/16/2026
In alignment with its carbon reduction commitments, India is transitioning towards higher ethanol-blended fuels, with E20 set for nationwide implementation by 2025. Ethanol is a renewable, domestically produced biofuel produced through fermentation of biomass such as sugarcane, corn. It possesses a higher octane rating and oxygen content compared to conventional gasoline, making it a favorable additive for improving engine performance and reducing emissions. This study investigates the impact of E20 fuel on performance parameters of a 694 cc MPFI , water-cooled, twin-cylinder gasoline engine. For deriving maximum benefits of increased Octane rating of E20, compression ratio was increased to 12.5:1. Experimental analysis was conducted to assess the changes in combustion behavior, brake specific fuel consumption (BSFC), torque output, engine out emissions and thermal efficiency when operating on E20 compared to baseline gasoline (E10). Base results indicate that E20 promotes more
Kulkarni, Deepak, Malekar, Hemant A, Thonge, Ravindra, Kanchan, Shubham
Misfires Detection in Bi-Fuel Engines – A Brief Note2026-26-01201/16/2026
With the expansion of compressed natural gas (CNG) filling station in India, bi-fuel vehicles are gaining popularity in recent times. Bi-fuel engine runs on more than one fuel, say in both CNG and petrol. Hence, the engine must be optimized in both the fuel modes for performance and emissions. However, due to the inherent differences in combustion characteristics: ignition dynamics and fuel properties, they pose a significant challenge in case of detection of misfires. Misfires are caused because of faulty injection systems and ignition systems and incorrect fuel mixture. Accurate detection is essential as misfires deteriorate the catalysts performance and may impacts emission. Misfires (or engine roughness) is calculated from engine crankshaft speed signal. In this study, the effectiveness of crankshaft-based misfires detection method, comparison of misfire signals magnitude in bi-fuel modes and practices developed for accurate detection of misfires is presented.
Thiyagarajan, Abhinav, N, Gobalakrishnan, R, Hema
Comprehensive Engine Testing Methodologies for Hydrogen Internal Combustion Engine Validation with Combustion & Performance Evaluation Techniques2026-26-02561/16/2026
Validation of hydrogen-fuelled internal combustion engine (H2 ICE) is critical to assess its feasibility as sustainable transportation with zero carbon emissions. This experimental analysis conducted on Ashok Leyland’s 6cylinder 2V engine to evaluate the engine performance & durability with hydrogen fuel. Combustion behaviour of hydrogen ICE needs to be closely monitored during continuous operation of validation testing, due to its unique properties compared to other conventional fuels. During engine run, a pre-ignition source can cause knock event leading to instant failure of critical parts like piston assembly, spark plug, liner, valves & cylinder head. Also, hotspots inside IMF leads to backfire affecting the air intake & fuel injection assembly. This study emphasizes the significance of precise instrumentation of thermocouples across engine on cylinder head, intake manifold & exhaust manifold, to detect performance detoriation and combustion abnormalities causing knocking
Vasudevan, Sindhuja, J, Narayana Reddy, Bolar, Yogesh Ganesh, Pandey, Sunil, N, Harish, N R, Varatharaj, Karthikeyan, K, Kumar D, Kishore
Development of High BMEP Natural Gas Engine with Knock Mitigation2026-26-01211/16/2026
The stringent emission norms over the past few years have driven the need to use low-carbon fuels and after treatment technology. Natural gas is a suitable alternative to diesel heavy-duty engines for power generation and transportation sectors. Stoichiometric combustion offers the advantages of complete combustion and low carbon dioxide emissions. Turbocharging and cooled exhaust gas recirculation (EGR) technology enhances the power density along with reduced exhaust emissions. However, there are several constraints in the operation of natural gas spark ignition engine such as exhaust gas temperature limit of 780 °C, sufficient before turbine pressure for EGR drivability, boost pressure, peak cylinder pressure limit and knocking. These limits coulld restrict the engine BMEP (brake mean effective pressure). In the present study, tests were conducted on a V12, 24 liters, heavy duty natural gas fuelled spark ignition engine (600 HP) with different EGR and turbocharger configurations to
Khaladkar, Omkar, Marwaha, Akshey
Artificial Neural Network-Based Performance and Emission Prediction for Hydrogen-Combustion Multicylinder Engines2025-36-023712/18/2025
In response to the pressing need to reduce greenhouse gas emissions from the transportation sector, hydrogen-fueled internal combustion engines (H2ICEs) have emerged as a promising alternative to conventional fossil-fueled powertrains. However, optimizing H2ICEs presents challenges in balancing performance with emissions, particularly in nitrogen oxide (NOx) formation This study proposes a data-driven methodology using an artificial neural network (ANN) to predict key emission and performance metrics: NOx emissions, brake mean effective pressure (BMEP), brake specific fuel consumption (BSFC), brake power, and brake thermal efficiency, based solely on engine operational parameters. Experimental data were collected from a three-cylinder Ford EcoBoost engine under varying conditions of intake pressure, spark timing, air-fuel ratio, engine speed, and valve timing. Feature selection was performed using the Spearman correlation coefficient, identifying engine speed, start of injection angle
Pasa, Bruno Roberto, Silveira, Juliano Pereira, Fagundez, Jean Lucca Souza, Lanzanova, Thompson Diórdinis Metzka, Martins, Mario Eduardo Santos, Salau, Nina Paula Gonçalves
Optimization of Biogas Combustion in SI Engines Applied to the Pre-Chamber Ignition System2025-36-020912/18/2025
The diversification of the energy matrix, combined with the use of renewable and less polluting fuels in internal combustion engines, has encouraged numerous research efforts both nationally and internationally. In this context, the utilization of waste for biofuel production stands out as a promising alternative, offering a clean and economically viable energy source. Biogas is one of the most sustainable options and has been widely used in the industry. However, it presents low lower heating values (LHV) and difficulties in burning stoichiometric mixtures, which compromise engine performance, resulting in higher specific fuel consumption and lower power output compared to fossil fuels. To address this challenge, this study aimed to improve biogas combustion in internal combustion engines by investigating the application of a new pre-chamber ignition system in the combustion process and engine performance parameters. For this, experimental tests were conducted with two biofuel
Siqueira, Caio Henrique Moreira, Ázara, Luiz Eduardo Martins, Ribeiro, José Vitor Puttini, Soares, Gabriel Faria, Silva, Fábio Moreira, Alvarez, Carlos Eduardo Castilla
Turbulent Jet Ignition Engine: Calibration of Flame Multipliers for Combustion Model2025-36-023912/18/2025
With the implementation of increasingly stringent regulations for pollutant emissions, such as Proconve L8 [1], which requires a 37% reduction in NOx and non-methane organic gases (NMOG) emissions for light passenger vehicles compared to previous regulations, the automotive engineering community is constantly evolving to develop prediction models that are capable of predicting the performance of Internal Combustion Engines (ICE). With this, the society search solutions to increase fuel conversion efficiency and reduce fuel emissions. In a special case, related to the study of the turbulent jet ignition (TJI) engine, there was a need to develop a refined numerical model that allows for the accurate design of the ignition pre-chamber geometry. In view of this, a one-dimensional modeling was carried out in the GT-SUITE ® software, in its modeling environment for Internal Combustion Engines (ICE), GT-POWER ®, with the objective of determining its ideal volume, parameters such as internal
Silva, Arthur Medeiros, Souza, Ediwaldo Júnio de, Rocha, Hiago Tenório Teixeira Santana, Filho, Fernando Antônio Rodrigues, Guzzo, Márcio Expedito, Oliveira, Wender Pereira de, Baeta, José Guilherme Coelho
Numerical Analysis of the Performance of an Engine with a Pre-Chamber Equipped with an Air Injector Operating in TJI Mode2025-36-018712/18/2025
The sustainability of the transportation sector demands the continuous development of new technologies in internal combustion engines, aiming at reducing pollutant and greenhouse gas emissions while increasing fuel conversion efficiency. Pre-chamber (PC) ignition systems have recently emerged as an important technological pathway to explore. These systems generate turbulent combustion gas jets capable of accelerating flame propagation in the main chamber. The use of this mechanism enables a more homogeneous and efficient combustion, as well as allowing an increase in the compression ratio, resulting in improvements in engine performance and a reduction in pollutant emissions. One of the strategies to further enhance the benefits of pre-chambers is the introduction of air injectors. The objective of this modification is to promote the cleaning of residual gases that remain in the pre-chamber after combustion, mitigating adverse effects such as mixture dilution and ignition instabilities
Rocha, Hiago Tenório Teixeira Santana, Oliveira, Wender Pereira de, Filho, Fernando Antonio Rodrigues, Baeta, José Guilherme Coelho, Guzzo, Márcio Expedito, Assis, Marcelo Suman Silva, Moreira, Thiago Augusto Araujo
Performance Analysis of Methanol- Ethanol Blend Fuel in a Spark-Ignition Flex-Fuel Engine2025-36-014812/18/2025
Flex-fueled vehicles (FFV) dominate the Brazilian market, accounting for over 75% of the national fleet. Ethanol fuel is widely used, primarily in the form of hydrated ethyl alcohol fuel (HEAF). Given the similar physicochemical properties of ethanol and methanol, fuel adulteration is a growing concern, often involving the addition of anhydrous ethanol, methanol, or even water to hydrated ethanol. These adulterants are visually imperceptible and can only be detected through analyses conducted by regulatory agencies using specialized instruments. However, they can significantly affect vehicle performance and accelerate engine component deterioration. The experiment was performed with a small displacement 3-cylinder port fuel injection flex-fuel engine on an engine test bench (dynamometer) and compared when fueled with ethanol and methanol. Data acquisition included combustion pressure, spark plug temperature, torque, air-fuel ratio, fuel flow, spark maps, and the overall effects of
Mascarenhas, Giovana Rebellato, Gomes, Ederson, Cruz, Diego, Duque, Edson Luciano
A Review of the Application and Research Progress of Turbulent Jet Ignition Technology03-18-08-004712/3/2025
For the sustainable development of human society, energy saving, emission reduction, and carbon reduction are urgent challenges to be addressed in the energy industry. As a power device for energy conversion in the transportation sector, the internal combustion engine also needs to enhance its thermal efficiency while cutting pollutant emissions. To meet the current stringent requirements, lean combustion has been widely studied as an effective strategy. However, the ignition difficulty resulting from lean burn needs to be addressed. As a high-energy ignition system, the prechamber turbulent jet ignition can accelerate in-cylinder combustion, thereby enhancing engine efficiency and reducing emissions. Thus, it is considered a promising technology. This review reveals efforts to apply prechamber ignition systems to optimize combustion in the engine characterized by low-carbon fuels and low-emission features. First, this article briefly introduces the evolution of the prechamber
Bai, Xiujuan, Zheng, Dayuan
Visualization of Ammonia Engine by Pre-Chamber Igniter2025-01-053011/25/2025
Ammonia is considered more and more as a promising carbon-free fuel for internal combustion engines to contribute to the decarbonization of several sectors where replacing conventional engines with batteries or fuel cells remains unsuitable. However, ammonia properties can induce some challenges for efficient and stable combustion. This study investigates the use of an active pre-chamber ignition system fueled with hydrogen and compares it to conventional spark ignition, with a focus on lean limit operation and early flame development. Experiments were conducted on a single cylinder optical engine with a compression ratio of 9.5, equipped with a quartz window in the piston for natural flame luminosity imaging using a high-speed camera. The engine was fueled with a mixture of 95% ammonia and 5% hydrogen by volume. Ammonia was injected and mixed with air in the intake port while hydrogen was directly injected into the prechamber. As a function of the intake pressure (1.0, 0.9, 0.8, and
Rousselle, Christine Mounaim, Brequigny, Pierre, Gelé, Raphaël, Moreau, Bruno
Ammonia Combustion with Active Pre-Chamber Spark Plug - A CO 2 -Free Combustion Process2025-01-052711/25/2025
As a zero-carbon fuel, ammonia has the potential to completely defossilize combustion engines. Due to the inert nitrogen present in the molecule, ammonia is difficult to ignite or burn. Even if the ammonia can be successfully ignited, combustion will be very slow and there is a risk of flame quenching, i.e. the flame going out before the ammonia-air mixture has been almost completely converted. Both the difficult flammability and the slow combustion result in high ammonia slip, which should be avoided at all costs. The engine efficiency is also greatly reduced. Safe ignition and burn-through can be achieved by drastically increasing the ignition energy and/or using a reaction accelerator such as hydrogen. The planned paper will use detailed 1D and 3D CFD calculations to show how high the potential of ammonia combustion in an internal combustion engine is when an active pre-chamber is used as the ignition system. As a result of the flame jets penetrating into the main combustion chamber
Sens, Marc, von Roemer, Lorenz, Rieß, Michael, Fandakov, Alexander, Casal Kulzer, Andre
Multi-Objective Optimization of Oxyfuel Gas Engine Using Stochastic Engine Model and Detailed Chemistry2025-01-052911/25/2025
The energy transition initiatives in Germany’s renown coal mining region Lusatia have driven research into Power-to-X-to-Power technologies, where synthetic fuel is produced from renewably sourced hydrogen and captured CO2, and converted to electricity and heat through oxyfuel combustion. This work investigates the multi-objective optimization of oxyfuel gas engine using a stochastic engine model and detailed chemistry. Exhaust gas recirculation (EGR) rate, initial cylinder temperature and pressure, spark timing, piston bowl radius and depth are selected as design parameters to minimize the exhaust temperature at exhaust valve opening and indicated specific fuel consumption (ISFC) corresponding to oxyfuel operation with different dry and wet EGR rates. The optimization problem is solved for a dry EGR and four wet EGR cases with various CO2/H2O fractions, aiming to achieve comparable performance as in conventional natural gas / air operation, and energy-efficient carbon capture. The
Asgarzade, Rufat, Franken, Tim, Mauss, Fabian
Investigation of Active Pre-Chamber Ignition on an Optically Accessible Ultra-Lean DI Hydrogen Engine2025-01-052411/25/2025
Hydrogen is a promising alternative to conventional fuels for decarbonizing the commercial vehicle sector due to its carbon-free nature. This study investigates the ignition and flame propagation characteristics of hydrogen in a 2-liter single-cylinder optical research engine representative of the commercial vehicle sector. The main objective was to enable high power density operation while minimizing NOx emissions. For that, ultra-lean combustion was employed to lower in-cylinder temperatures, addressing the challenge of NOx formation. To counteract delayed and unstable combustion under lean conditions, an active pre-chamber ignition system was implemented. It uses a gas-purged pre-chamber with separate hydrogen injection and spark plug ignition. Turbulent hot gas jets from the pre-chamber ignite the fresh mixture in the main combustion chamber, enabling faster and more stable ignition compared to conventional spark plugs. Additionally, the low volumetric energy density of hydrogen
Borken, Philipp, Bill, Daniel, Link, Lukas, Dinkelacker, Friedrich, Hansen, Hauke
Optimization of Injection Parameters for a Free-Piston Engine Equipped with Flat-Head Combustion Chamber2025-01-507511/11/2025
The free-piston engine represents a paradigm shift in internal combustion engine technology, with its unique structure promising efficiency gains. However, injection parameters are one of the core elements of free-piston engine performance. This study employs computational fluid dynamics analysis to optimize the spray cone angle and start of injection timing for a two-stroke dual-piston opposed free-piston engine equipped with a flat-head combustion chamber. A three-dimensional transient model incorporating dynamic adaptive mesh refinement was constructed by using CONVERGE 3.0 software. The results indicate that a spray cone angle of 25° achieves optimal fuel distribution, yielding a peak indicated thermal efficiency of 42.14% and an indicated mean effective pressure of 9.08 bar. Crucially, advancing the ignition timing to 215°CA improves mixture homogeneity but simultaneously increases peak cylinder temperatures and NOx. Conversely, delayed start of injection timings reduces NO
Xu, Zhaoping, Yang, Shenao, Liu, Liang
High-Tension Ignition CableJ2031_202511 (Current)11/6/2025
The specifications contained in this SAE Standard pertain to high-tension ignition cable used in road vehicle engine ignition systems.
Ignition Standards Committee
Development of a Combined Injection and Ignition Unit for a Gas Engine with Direct Hydrogen Injection Integrated into the Standard Spark Plug Access Hole2025-32-005911/3/2025
To achieve the desired fuel switch from natural gas to hydrogen in internal combustion engines for combined heat and power units, it is necessary to make some adjustments to the fuel supply system. External gas mixers increase the probability of backfiring when natural gas is replaced by hydrogen. In addition, the low density of hydrogen results in a loss of power. Therefore, direct gas injection is preferred when using hydrogen. A drawback of direct injection is the requirement of higher injection pressures to achieve the desired fuel mass and mixture homogeneity as well as the additional access to the combustion chamber for the direct gas injector in the cylinder head. This paper proposes an alternative approach that does not necessitate the implementation of a high-pressure direct injection system nor additional access to the combustion chamber via the cylinder head. A combined injection and ignition unit, called HydroFit, was developed which uses a sleeve inside the spark plug bore
Rischette, Nic, Holzberger, Sascha, Helms, Sven, Kettner, Maurice
Clarification of the Mechanism of Abnormal Combustion in Hydrogen Engines -Investigation of Abnormal Combustion Location by Visualization Measurement-2025-32-006411/3/2025
Hydrogen internal combustion engines present a promising path towards carbon neutrality, yet their development is challenged by abnormal combustion phenomena like backfire and pre-ignition. These phenomena limit engine torque and reduce component reliability. This study is aimed to elucidate the mechanisms behind these phenomena in hydrogen internal combustion engines. We utilized a multi-cylinder engine with optical access for direct high-speed imaging of in-cylinder processes to visualize backfire and pre-ignition. Initial analysis, combining visualization data with one-dimensional (1D) simulations, indicated that high temperatures of the ground electrode of the spark plug could be a key trigger factor for abnormal combustion. To investigate this hypothesis, the surface temperature of the ground electrode was measured under firing conditions using a two-color thermometry system. The measurements revealed that the electrode temperature exceeded the compressed gas temperature near Top
Muramatsu, Keiji, Tokuhara, Satoshi, Kadu, Pravin, Yoshimura, Kei, Nakama, Kenjiro
Analysis of Flame Propagation Characteristics in a Hydrogen Engine using an Optically Accessible Engine2025-32-006111/3/2025
This study focused on the effects of hydrogen on the flame propagation characteristics and combustion characteristics of a small spark-ignition engine. The combustion flame in the cylinder was observed using a side-valve engine that allowed optical access. The fundamental characteristics of hydrogen combustion were investigated based on combustion images photographed in the cylinder with a high-speed camera and measured cylinder pressure waveforms. Experiments were conducted under various ignition timings and equivalence ratios and comparisons were made with the characteristics of an existing hydrocarbon liquid fuel. The hydrogen flame was successfully photographed, although it has been regarded as being difficult to visualize, thus enabling calculation of the flame propagation speed. As a result, it was found that the flame propagation speed of hydrogen was much faster than that of the existing hydrocarbon fuel. On the other hand, it was difficult to photograph the hydrogen flame
Arai, Yuto, Ueno, Takamori, Suda, Ryosuke, Sato, Ryoichi, Nakao, Yoshinori, Ninomiya, Yoshinari, Matsushita, Koichiro, Kamio, Tomohiko, Iijima, Akira
Effect of Plasma-Assisted Ignition on Combustion and Emission Characteristics of Two Stroke Engines with Different Fuels2025-32-003011/3/2025
This study explores the effect of plasma-assisted ignition (PAI) on combustion stability and emissions in two-stroke spark-ignition engines. Two engine platforms were evaluated: a conventional single-cylinder two-stroke engine and a thermodynamically advanced opposed-piston two-stroke (OP2S) engine. The OP2S engine configuration offers reduced heat loss and higher power density due to its uniflow scavenging and favorable geometry, but suffers from high residual gas fraction, which increases ignition difficulty and combustion instability. To address this, nanosecond-pulsed PAI was applied in various spatial arrangements and discharge voltages, using both gasoline and a low-reactivity gasoline/DMC blend fuel. Spark ignition timing was held constant at the minimum advance for best torque across all tests. Combustion stability was assessed via indicated mean effective pressure (IMEP) and its coefficient of variation, while CO and HC emissions were measured as environmental indicators
Liu, Jinru, Yamazaki, Yoshiaki, Otaki, Yusuke, Kato, Hayato, Kobayashi, Daichi, Umegaki, Tetsuo, Asai, Tomohiko, Iijima, Akira
A Study of Knocking Characteristics in a Hydrogen SI Engine under High Compression Ratio2025-32-006311/3/2025
This study investigated the knocking characteristics of a hydrogen spark ignition engine for the purpose of increasing efficiency and expanding the operating range. In recent years, research focused on carbon neutrality has been vigorously conducted, and hydrogen has attracted attention as a next-generation fuel for internal combustion engines (ICEs). The combustion characteristics of hydrogen are vastly from those of existing gasoline. It is essential to have a sufficient understanding of the combustion characteristics of hydrogen in order to develop next-generation ICEs designed to operate on hydrogen fuel. There are especially many aspects of the knocking mechanisms of hydrogen that are unclear. Consequently, those characteristics and mechanisms must be clarified for the purpose of expanding the operating range of hydrogen engines and enhancing their efficiency. In this study, experiments were conducted using a single-cylinder hydrogen engine that was operated at a high compression
Ishihara, Hiromasa, Kishibata, Shunsuke, Miyake, Shota, Iida, Tomoya, Kuwabara, Kenta, Yoshihara, Shintaro, Miyamoto, Sekai, Iijima, Akira
Knock Sensors for Two Wheelers Applications2025-32-007911/3/2025
This paper describes the design and characteristics of the knock sensor. The sensor is already used as a commodity product for automotive applications and used by all automotive OEMs for spark ignited combustion engines. With the arrival of the electronic fuel injection on the two wheelers, further optimization of the combustion can be obtained. Although there are many publications on the engine knock strategy, little is known publicly about the sensor itself. The knock sensor is an accelerometer based on a piezoelectric component; it provides an analog signal of the engine vibration. The Electronic Control Unit will filter the signal according to a specific strategy and defines the presence and intensity of the engine knock. The ECU will act accordingly on the ignition timing. The inner structure as well as the mechanical and electrical interface are described in this article.
van Est, Jeroen, Prieu, Corentin
Experimental Study of hCNG on Single Cylinder 395cc Spark Ignition Engine for Performance and Exhaust Emission2025-32-005011/3/2025
There is growing demand for energy utilization due to stricter environmental emission norms to reduce greenhouse gases and other threats posed due to the emissions are major motivation factors for researchers to adopt on strategic plans to decrease the usage of energy and reduce the carbon contents of fuels, the usage of hydrogen or blend of hydrogen with CNG as a fuel in internal combustion engines is the best option. As hydrogen has lower volumetric energy density and higher combustion temperature, pure hydrogen-fueled engines produce lower power output and much higher NOx emissions than gasoline-fueled engine at stoichiometric air-fuel ratio. Blending of hydrogen with CNG provides a blended gas termed as hydrogen-enriched natural gas (hCNG). hCNG stands for hydrogen enriched compressed natural gas and it combines the advantages of both hydrogen and methane. The addition of Hydrogen to CNG has potential to even lower the CNG emissions and is the first step towards promotion of a
Syed, Kaleemuddin, Chaudhari, Sandip, Khairnar, Girish, Sajjan lng, Suresh
Study on Combustion Detection of a Spark-Ignition Engine with Fuel Variation Using Various Sensors2025-32-005211/3/2025
The use of alternative fuels, such as biofuels and synthetic fuels in small mobility engines has become more common these days. Although these fuels contribute to the carbon neutrality, it is known that they do not have a certain fuel composition, which significantly affects the combustion characteristics of an engine, such as knocking and combustion duration. Therefore, to get the most out of these sustainable fuels, it is necessary to develop engine systems that are highly robust to variations in fuel composition. To achieve this goal, a method to sense fuel characteristics onboard using sensors already widespread in use or can be installed inexpensively is required. Although in-cylinder piezoelectric pressure sensors are useful for research in the laboratory, it is not suitable for the use in commercial engines because of its high cost. Therefore, the use of other sensors should be considered. The purpose of this study is to experimentally analyze what information related to
Hayashi, Kohei, Kim, Jihoon, Yamasaki, Yudai
Computational Investigation on a Boosted Uniflow Scavenged Direct-Injection Combustion Engine (BUSDICE) with Alcohol Fuels2025-32-002711/3/2025
Alcohol fuels, produced from renewable energy sources, are considered a crucial solution for achieving life-cycle carbon neutrality in internal combustion engines. The Boosted Uniflow Scavenged Direct-Injection Combustion Engine (BUSDICE) exhibits significant potential for high thermal efficiency with an aggressive downsizing design. In this study, a computational investigation was carried out to assess the spray mixing and combustion characteristics of BUSDICE fuelled with methanol and ethanol, compared with gasoline, under a high-load condition. The injection duration of methanol and ethanol is significantly longer than that of iso-octane, leading to incomplete evaporation. The mixture exhibits an “outer-rich, central-lean” stratification pattern due to the short mixing time and swirl flow transportation for all three fuels. However, the prolonged injection of methanol induces stronger turbulence, which can enhance the local mixing. The spatial mixture stratification, particularly
Feng, Yizhuo, Lu, Enshen, Dong, Shuo, Keshtkar, Hossein, Wang, Xinyan, Zhao, Hua
Development of Anti-SideSlip Control for Motorcycles Using IMU2025-32-003711/3/2025
In motorcycle racing and other competitions, there is a technique to intentionally slide the rear wheel to make turns more quickly. While this technique is effective for high-speed riding, it is difficult to execute and carries risks such as falling. Therefore, an anti-sideslip control system that suppresses unintended or excessive sideslip is needed to ensure safe, natural, and smooth turning. In anti-sideslip control, the slip angle is usually used as a control parameter. However, for motorcycles, it is necessary to know the absolute direction of the vehicle's movement. To determine this, GPS or optical sensors are required, but using such sensors for driving is costly and may not provide accurate measurements due to contamination or other environmental factors, making it impractical. Therefore, an anti-sideslip control system was developed by calculating another parameter that indicates the characteristics of the slip angle, without measuring the slip angle itself, thus eliminating
Nakano, Kyosuke, Kawai, Kazunori, Takeuchi, Michinori
Firing TDC Identification Through Wasted Spark Duration Measurements During Cranking of Small Engines2025-32-008511/3/2025
Implementing control techniques through “virtual sensors” is extremely attractive for small size engines, given that cost effectiveness is essential. This work presents a routine for identifying the firing TDC through measurement of spark duration. Previous capability of correctly identifying cycle phasing through this route was confirmed during normal operation of a power unit that featured a wasted spark ignition system. Starting with the hypothesis that this could be implemented during engine cranking, the procedure was adapted for identifying the firing TDC as quickly as possible; it was also developed with the specific task of requiring less time for synchronization, compared to the previous version. The new method was verified on a small size 50 cc single cylinder engine that featured a recoil starter mechanism. Correct identification was confirmed, with the possibility of generating the reference signal as early as the 2nd cycle that featured normal operation of the ignition
Irimescu, Adrian, Merola, Simona
Investigation of Transient High Current Ignition for Lean Mixture in Spark Assisted Compression Ignition2025-01-039010/7/2025
Lean burn combustion is an effective strategy to reduce the in-cylinder temperature. Hence reduce NOx emissions and increase the thermal efficiency of the system. One essential aspect of successful combustion is the flame kernel initiation and development. However, as the fuel-air mixture becomes leaner, challenges arise in achieving a stable flame kernel initiation and a moderate speed of flame propagation. This empirical research aims to investigate the impact of the transient high current ignition strategy on flame kernel development, flame propagation and auto-ignition timing of lean Dimethyl Ether (DME). In this work, a rapid compression machine is employed at engine-relevant conditions, a pressure of ~15 bar and temperature of ~650K. Spark-assistance is applied at the end of compression to enable a spark-assisted compression ignition combustion mode. The spark event is initiated by a transient high current ignition system, which includes a traditional transistorized coil ignition
Asma, Sabrina, Yu, Xiao, Jin, Long, Tjong, Jimi, Zheng, Ming
Items per page:
1 – 50 of 2084