Browse Topic: Engine components

Items (22,675)
Cam gear is a critical component of the timing system in an internal combustion engine, ensuring the synchronized opening of the engine valves, pistons, and rotating parts, but their unavailability may result in long-term downtime or expensive replacement. Reverse engineering (RE) systems also play an important role in promoting sustainable practices projects in automotive technologies. The study focuses on presenting a proposed method for redesigning damaged parts in engines using image processing technology by creating an-accurate CAD model. In addition to clarifying of the expected causes that led to cam gear damage. The proposed method involves taking a high-resolution image of the damaged part, then applying advanced image processing algorithms to analyze and reconstruct the geometry of the part. The data is then converted into a high-resolution 3D CAD model. This approach aims to address the challenges of replicating worn or broken parts, providing a cost-effective maintenance
Ali, Salah H. R.Ehab, EslamBarakat, EbrahimYounes, AbdelrahmanAli, Amr S.H.R.
Optimizing engine mounting systems is a complex task that requires balancing the isolation of vehicle vibrations with controlling powertrain movement within a limited dynamic envelope. Six Degrees of Freedom (6DOF) optimization is widely used for mounting stiffness and location optimization. This study investigates the application of various optimization algorithms for 6DOF analysis in engine mount design, where the system’s stochastic behaviour and probabilistic characteristics present additional challenges. Selecting an appropriate optimization framework is essential for achieving accurate and efficient NVH results. Recent advancements in research have introduced several 6DOF optimization algorithms to determine the optimal stiffness and location of engine mounts. The study evaluates a range of optimization methods, including Simultaneous Hybrid Exploration that is Robust, Progressive and Adaptive (SHERPA), Quadratic Programming (QP), Genetic Algorithm (GA), Particle Swarm
Hazra, SandipKhan, Arkadip
The operating temperature of lithium-ion battery (LIB) cells significantly influences their degradation behavior. In indirect liquid cooling systems, temperature variations within a Battery Electric Vehicle (BEV) LIB module are inevitable due to the increasing downstream temperature of the cooling medium as it absorbs heat. This leads to reduced temperature differentials between the cooling medium and the LIB cells. As a result, LIB cells located further along the flow path experience higher average temperatures than those at the front. Typically, a maximum average cell temperature difference of 5 K within LIB modules is considered acceptable. However, results from a conventional cooling system indicate that, when fast charging is exclusively used, this can lead to a 15.5 % difference in the total ampere-hours passed before the End-of-Life (EOL) is reached for the front and back LIB cells. To address this issue, a switchable thermal management system for the traction battery is
Auch, MarcusWeyershäuser, KonstantinKuthada, TimoWagner, Andreas
Low-carbon alternatives to diesel are needed to reduce the carbon intensity of the transport, agriculture, and off-grid power generation sectors, where compression ignition (CI) engines are commonly used. Acid-catalysed alcoholysis produces a potentially tailorable low-carbon advanced biofuel blend comprised of mixtures of an alkyl levulinate, a dialkyl ether, and the starting alcohol. In this study, model mixtures based on products expected from the use of n-butanol (butyl-based blends) as a starting alcohol, were blended with diesel and tested in a Yanmar L100V single-cylinder CI engine. Blends were formulated to meet the flash point, density, and kinematic viscosity limits of fuel standards for diesel, the 2022 version of BS 2869 (off-road). No changes to the engine set-up were made, hence testing the biofuel blends for their potential as “drop-in” fuels. Changes in engine performance and emissions were determined for a range of diesel/biofuel blends and compared to a pure diesel
Wiseman, ScottLi, HuTomlin, Alison S.
This work is part of a production-intent program at Cummins to develop a 6.7L direct injection (DI), lean burn H2 spark ignition (SI) engine for medium- and heavy-duty commercial vehicles that are intended to be compliant with global VII criteria pollutants emissions standards. The engine features a low-pressure DI fuel injection system, a tumble-based combustion system with a pent-roof combustion chamber, two-stage boosting system without EGR, and dual overhead cams (DOHC) with cam phasers. The paper focuses primarily on the performance system architecture development encompassing combustion system, air-handling system, and valve strategy. Comprehensive 3D-CFD guided design analysis has been conducted to define the tumble ports, injection spray pattern, and injection strategy to optimize charge homogeneity and turbulence kinetic energy (TKE). In addition, the boosting system architecture and the valve strategy have been thoroughly evaluated through 1-D system-level engine cycle
Liu, LeiZhang, YuQin, XiaoHui, HeMin, XuLeggott, Paul
A hierarchical control architecture is commonly employed in hybrid torque control, where the supervisor CPU oversees system-level objectives, while the slave CPU manages lower-level control tasks. Frequently, control authority must be transferred between the two to achieve optimal coordination and synchronization. When a closed-loop component is utilized, accurately determining its actual contribution to the controlled system can be challenging. This is because closed-loop components are often designed to compensate for unknown dynamics, component variations, and actuation uncertainties. This paper presents a novel approach to closed-loop component factor transfer and coordination between two CPUs operating at different hierarchical levels within a complex system. The proposed framework enables seamless control authority transition between the supervisor and slave CPUs, ensuring optimal system performance and robustness. To mitigate disturbances and uncertainties during the transition
Rostiti, CristianBanuso, AbdulquadriKarogal, Indrasen
The future heavy duty powertrain market is expected to be more diverse, with a gradual shift towards cleaner and more sustainable alternative fuels. Among various options, the hydrogen Internal Combustion Engine (ICE) holds the promise of significantly reducing carbon emissions while leveraging existing ICE technology. However, it also faces substantial challenges related to engine performance, fuel storage and delivery, infrastructure development, economic feasibility, safety and market acceptance. This paper focuses on performance challenges of hydrogen engine, including knock and pre-ignition, as well as low thermal efficiencies, and introduces the Opposed-Piston Two-Stroke Hydrogen ICE (OP2S-H2ICE) as a potential solution. The study demonstrates that OP2S-H2ICE can operate using direct injection, compression-ignition (CI) combustion solely with hydrogen, under various low-load to partial load conditions. Specifically, as the load increases, the combustion transitions from partial
Huo, MingEl-Hannouny, EssamLongman, Douglas
The heat transfer processes occurring in a compression ignition engine are complex, especially considering flame-wall interaction on the piston crown from impinging jets. To study the heat flux occurring on the piston in a heavy-duty diesel engine, a piston was instrumented with fifteen thermocouples and a wireless telemetry system. Eight of the thermocouples are high speed surface thermocouples placed primarily in regions with significant flame-wall interaction, providing crank-resolved surface temperature data. This work presents the first experimental datasets collected with this instrumented piston, describing in detail the thermocouple location selection process as well as data processing and uncertainty quantification for the high-speed surface thermocouples with a particular emphasis on cyclic variability and sensor-to-sensor variability. With this methodology established, data from this piston can be used for modeling and simulation studies as well as for studying the impact of
Gainey, BrianDatar, AdityaRavikumar, AvinashBhatt, AnkurVedpathak, KunalKumar, MohitGingrich, EricTess, MichaelKorivi, VamshiLawler, Benjamin
Internal combustion engines (ICEs) will continue to be critical propulsion systems for certain applications in the coming decades. It is, therefore, extremely important to further develop environmentally friendly and sustainable internal combustion engines. These developments include, but are not limited to, improved tribology and reduced mechanical losses, higher mean effective pressures, compatibility with carbon-free or -neutral fuels, improved exhaust gas aftertreatment systems, and condition-based maintenance. Due to the increased stress on engine components associated with these changes, accurate, online data with high temporal resolution is required from inside the engine. Acquisition of this data can be achieved with a wireless telemetry system in order to minimize the influence of measurement devices on the measurement itself. This paper describes challenges in the development of telemetry systems for internal combustion engines. Systems for measuring the piston temperature
Higgs, AnselRossegger, BernhardMarzemin, FrancescoWermuth, Nicole
The Tour engine is a novel split-cycle internal combustion engine (ICE) that divides the four-stroke Otto cycle of a conventional ICE between two separate cylinders, an intake and compression cylinder and a second expansion and exhaust cylinder, interconnected by an innovative charge transfer mechanism. The engine working fluid, air and fuel, is inducted into the engine and compressed by a dedicated compression cylinder, transferred with minimal pressure loss via an input port to a specifically designed combined spool shuttle transfer mechanism and combustion chamber. It is then ignited and then transferred from the combustion chamber via an exit port to a separate expansion cylinder where it is expanded and exhausted from the engine. The primary advantage of the Tour engine is that it provides the engineering freedom to independently design, control and optimize the compression, combustion, and expansion processes within a slider-crank piston engine. By decoupling the compression
Tour, OdedCho, KukwonHofman, YehoramAnderson, BradleyKemmet, RyanMorris, DanielWahl, MichaelBhanage, PratikSivan, EhudTour, GiladAtkinson, ChrisTour, Hugo
One of the most critical enablers of hydrogen internal combustion engines is achieving rapid injection and mixing of hydrogen into the combustion chamber. Optimal cap is actively being investigated to improve the injector performance without major hardware modifications. In this study, detailed computational fluid dynamics simulations using the Reynolds-averaged Navier-Stokes (RANS) turbulence model were undertaken to investigate the behavior of hydrogen jets with various cap designs mounted on a hollow-cone injector within a constant volume chamber. It was found that the implementation of a cap in general enhances mixture formation, leading to a higher proportion of lean mixture over time. Key parameters, such as the cap's inner volume and throat area ratio, directly influence the amount of hydrogen mass trapped within the cap. A smaller volume or larger throat area ratio results in less trapped hydrogen mass. Excessive enlargement of the cap's throat area can lead to a decrease in
Zaihi, AbdullahMoreno Cabezas, KevinLiu, XinleiBen Houidi, MoezWu, HaoAlRamadan, AbdullahCenker, EmreMohan, BalajiRoberts, WilliamIm, Hong
For Formula SAE cars, a significant increase in downforce can enable the car to score more points in the race and enhance the competitiveness of the vehicle. This paper focuses on the development of an active ground effect system driven by fans for the FSAE racing car. The system is designed to considerably increase the downforce of the racing car through the forced airflow generated by the fan, enable the dynamic adjustment of the aerodynamic balance of the racing car during the driving process, and achieve the vertical force control on the racing wheels, thereby improving the performance of the racing car. The Star-CCM+ software was employed to conduct CFD simulation to investigate the influence of different flow fans on downforce and optimize the layout and position of the fan. Due to the limited power that the car can carry, the paper will also simulate and calculate the range of pneumatic balance adjustment and vertical force control capability provided by the different openings
Yang, Chengyue
Drivers sometimes operate the accelerator pedal instead of the brake pedal due to driver error, which can potentially result in serious accidents. To address this, the Acceleration Control for Pedal Error (ACPE) system has been developed. This system detects such errors and controls vehicle acceleration to prevent these incidents. The United Nations is already considering regulations for this technology. This ACPE system is designed to operate at low speeds, from vehicle standstill to creep driving. However, if the system can detect errors based on the driver's operation of the accelerator pedal at various driving speeds, the system will be even more effective in terms of safety. The activation threshold of ACPE is designed to detect operational errors, and it is necessary to prevent the system from being activated during operational operations other than operational errors, i.e., false activation. This study focuses on the pedal operation characteristics of pedal stroke speed and
Natsume, HayatoShen, ShuncongHirose, Toshiya
Designing engine components poses significant challenges due to the long simulation times required to model complex thermal and mechanical loads, such as high-pressure forces, vibration, and fatigue. Accurate simulations are critical for ensuring component reliability and durability, but they are computationally intensive, leading to prolonged development timelines. In the fast-paced automotive industry, where meeting tight deadlines is essential, lengthy simulation processes create bottlenecks that hinder achieving optimal design outcomes on time. To address this, we utilize a Modified Extensible Lattice Sequence (MELS) approach combined with Design of Experiments (DOE). MELS generates low-discrepancy, space-filling sequences that ensure uniform coverage across the design space, minimizing clusters and gaps in experimental designs. This tool streamlines the simulation process, enabling engineers to explore broader design parameters and optimize components efficiently. By forecasting
Dhangar, VinaykumarGoswami, Somshree
Structural topology optimization for vehicle structures under static loading is a well-established practice. Unfortunately, extending these methods to components subjected to dynamic loading is challenged by the absence of sensitivity coefficients: analytical expressions are unavailable and numerical approximations are computationally impractical. To alleviate this problem, researchers have proposed methods such as hybrid cellular automata (HCA) and equivalent static load (ESL). This work introduces a new approach based on equivalent static displacement (ESD). The proposed ESD method uses a set of prescribed nodal displacements, simulating the resultant reaction forces of a body subjected to dynamic loading, at different simulation time steps to establish the boundary conditions for each corresponding model—one model for each simulation time. A scalarized multi-objective function is defined considering all the models. A gradient-based optimizer is incorporated to find the optimal
Gupta, AakashTovar, Andres
In the ongoing Road Load Data Acquisition (RLDA) for engine mounts, a load cell arrangement is being utilized, where the load cell must be placed between the mount arm and an engine mount bracket or an additional tower bracket. This configuration required the design of a custom mount arm with a crank in the Z direction, secured with a single bolt to accommodate the load cell. However, this method has revealed significant load coupling in the X and Z directions, resulting in incorrect load prediction for engine mount testing. This happens due to the architectural packaging of the engine mount on the long member to meet NVH requirements. To mitigate these issues, an alternative strain gauge-based RLDA approach was investigated. The optimal locations for strain gauge placement were determined using the inverse matrix method with the assistance of Computer-Aided Engineering (CAE) analysis. Strain gauges were then installed at these identified locations on the mount arm. The engine mount
Hazra, SandipKhan, ArkadipMohare, Gourishkumar
With the global shift towards sustainable and low-emission transportation, hydrogen-fueled engines stand out as a promising alternative to traditional fossil fuels, offering significant potential to reduce greenhouse gas emissions. This study provides a comprehensive evaluation of the performance and emissions characteristics of a hydrogen-powered heavy-duty compression ignition engine, which has been modified to operate as a Spark Ignition (SI) engine with a high compression ratio of 17:1. The evaluation was conducted across various speeds, loads, and spark timings under ultra-lean combustion conditions. The analysis utilized a modified 6-cylinder, 13-liter Volvo D13 diesel engine, configured to operate in single-cylinder mode with the addition of a spark plug for SI operation. The study examined key performance metrics, including brake thermal efficiency (BTE), power output, and specific fuel consumption, under the selected operating conditions. Emissions profiles for nitrogen oxides
Dyuisenakhmetov, AibolatPanithasan, Mebin SamuelCenker, EmreAlRamadan, AbdullahIm, HongTurner, James
India, with its low per capita income vast population and growing middle class, represents a significant market for low-cost, fuel-efficient automobiles. As the largest two-wheeler market globally, a transition to four-wheelers is underway, further driving the demand for affordable vehicles. This necessitates the design and development of low-priced vehicles equipped with efficient and economical powertrains. Globally, stringent regulations like Corporate Average Fuel Economy (CAFE), Worldwide Harmonized Light Vehicles Test Cycles (WLTC), and Real Driving Emissions (RDE) are pushing manufacturers to develop fuel-efficient vehicles. India has also adopted similar regulations, including CAFE2 and Bharat Stage 6-Phase 2 (BS6-2), to improve fuel economy and reduce emissions. These regulations, coupled with the growing demand for affordable vehicles, have spurred innovation in engine technology. In response to these challenges, Maruti Suzuki India Limited (MSIL) has consistently focused on
Singh, AmandeepSingh, JaspreetJalan, AnkitKumar, Narinder
Hybrid vehicles are driven by the vehicle controller, engine controller and motor controller through torque control, and there may be unexpected acceleration or deceleration of the vehicle beyond the driver's expectation due to systematic failure and random hardware failure. Based on the torque control strategy of hybrid vehicles, the safety monitoring model design of torque control is carried out according to the ISO 26262 safety analysis method. Through the establishment of safety goals and the analysis of safety concepts, this paper conducts designs including the driver allowable torque design for safety monitoring, the driver torque prediction design for safety monitoring, the rationality judgment design of driver torque for safety monitoring, the functional safety degradation design, and the engine start-stop status monitoring, enabling the system to transition to a safe state when errors occur. Firstly, the design of the driver's allowable torque includes the allowable requested
Jing, JunchaoWang, RuiguangLiu, YiqiangHuang, WeishanDai, Zhengxing
Ammonia is a carbon-free fuel alternative for the internal combustion engine decarbonization. However, its toxicity and less advantageous combustion characteristics including higher nitrogen-based engine-out emissions have delayed its use in power generation applications. Therefore, the use of a secondary and also carbon-free fuel such as hydrogen was proposed in the literature as a solution to promote and improve ammonia combustion while minimizing any modifications in engine parameters and control strategy that may be required when compared to using conventional hydrocarbon-based fuels. In addition, the higher resistance to autoignition of ammonia can allow operation at higher compression ratios in spark ignition applications, therefore increasing the thermal efficiency. The study presented here used a single-cylinder heavy-duty research engine converted to spark ignition operation to investigate medium load engine operation with ammonia-hydrogen blends in which hydrogen represented
Alvarez, LuisSaenz Prado, StefanyTrujillo Grisales, JuanDumitrescu, Cosmin
This paper presents an advanced control system design for an engine cooling system in an internal combustion engine (ICE) vehicle. Building upon our previous work, we have derived models for crucial temperatures within the engine, including combustion wall temperature, coolant-out temperature, block temperature, as well as temperatures in external components such as heat exchangers and radiator. To accurately predict these temperatures in a rapid manner, we have utilized a lumped parameter concept with a mean-value approach. This approach allows for precise temperature estimation while maintaining computational efficiency. Given the complexity of the cooling system, we have proposed a linear time-varying (LTV) model predictive control (MPC) system to regulate the temperatures. This control system linearizes the model at each time step and applies linear MPC over the control and prediction horizons. By doing so, we effectively control the highly nonlinear and time-delayed system
Chang, InsuSun, MinEdwards, David
A method for performance calculation and experimental method of a high voltage heater system in electric vehicles is proposed. Firstly, heater outlet temperature and pressure drop of the heater are used as metrics to compare simulation results with experimental data, thereby validating the established model. Then, simulations are performed on two heater flow channel configurations: a cavity flow channel and a cooling fin flow channel. It is observed that the latter significantly reduces the heating plate temperature. This reduction enhances the protection of heating elements and extends their operational lifespan, demonstrating the advantages of incorporating cooling fins into the flow channel structure. The optimization variables for multi-objective optimization include the fin unit length, fin height, fin thickness, fin width, and spacing between two adjacent rows of fins. The optimization objectives include pressure drop, heat transfer efficiency, and heating plate temperature
Gong, MingWang, XihuiWang, DongdongShangguan, Wen-Bin
The primary functions of mounts include providing structural support, sound insulation, and vibration damping. Dynamic stiffness and loss angle are critical metrics for evaluating their NVH (Noise, Vibration, and Harshness) performance. This paper examines a floating decoupler hydraulic mount featuring a long decoupler membrane track. A nonlinear lumped parameter model is developed to calculate the dynamic stiffness and loss angle. The model incorporates fluid flow in the lower chamber and variations in the support reaction force of the decoupler membrane under switching conditions. Parameters of the nonlinear lumped parameter model, including rubber stiffness, equivalent piston area, and volumetric compliance of the fluid chamber, were analyzed and calculated using the finite element method. The influence of different decoupler membrane track structures on the frequency corresponding to the minimum high-frequency dynamic stiffness was investigated based on the established model. The
Li, ShenghaoZhang, ShenglanYu, ChaoTu, XiaofengShangguan, Wenbin
Efficient thermal management is essential for maintaining the performance and safety of large-capacity battery packs. To overcome the limitations of traditional standalone air or liquid cooling methods, which often result in inadequate cooling and uneven temperature distribution, a hybrid air-liquid cooling structure was designed. A three-dimensional model was developed, and heat transfer and fluid flow characteristics were analyzed using computational fluid dynamics (CFD) simulations. Experimental validation was carried out through discharge temperature rise tests on individual battery cells and flow resistance tests on the liquid cooling plate. The thermal performance of the hybrid system was compared to that of standalone cooling methods under various discharge rates. The results indicated that the hybrid system significantly enhanced cooling performance, reducing the maximum temperature difference by 5.54°C and 3.37°C, and the peak temperature by 11.66°C and 4.5°C, compared to air
Li, HaoGuo, YimingZhou, FupengLi, KunyuanShangguan, Wen-Bin
The hydrogen internal combustion engine technology, with its potential for almost full carbon emissions reduction and adaptability to a wide range of fossil fuel-based internal combustion engine (ICE) platforms, offers a promising future. However, as with any innovative technology, it also presents challenges, such as abnormal combustion phenomena. These challenges, including intake backfire, which is more common when using port fuel injection (PFI), and pre-ignition in the combustion chamber, which can be experienced with PFI or direct injection (DI), require detailed investigation to understand and optimize the engine’s performance and efficiencies. This study comprehensively investigates the main abnormal combustion events that could happen in a spark ignition (SI) hydrogen engine. It examines both direct and port fuel injection systems and uses high-resolution in-cylinder, intake, and exhaust pressure measurements alongside a suite of fast-response gas analyzers. The study provides
Mohamed, MohamedMirshahi, MiladWang, XinyanZhao, HuaHarrington, AnthonyHall, JonathanPeckham, Mark
CNTs play an important role in modern engineering projects, especially in engine pistons design for the next-generation of motorcycles. This work presents a comprehensive analyses proposed project using finite element method under actual operating conditions purpose performance evaluation of a motorcycle engine piston design, investigating the suitability of four distinct materials. Precise material properties adhering to linear elastic isotropic behavior were defined within the software environment and proposed advanced nanomaterial ensuring accurate representations of the proposed under the prescribed loading scenarios. The primary objective was to identify the optimal material choice for the piston, ensuring superior strength, minimal deformation, and lightweight characteristics essential for high-performance engine applications. Moreover interpreting and understanding the dynamic behavior of common and advanced engineering materials. Through a comprehensive evaluation of the
Ali, Salah H. R.Ahmed, Youssef G. A.Ali, Amr S.H.R.
This research employs advanced Unsteady Reynolds-Averaged Navier-Stokes (URANS) simulations to analyze the transient multiphase flow dynamics within a four-cylinder inline (I-4) engine, with a focus on gas-liquid interface interactions and oil distribution phenomena. Utilizing a commercial three-dimensional Computational Fluid Dynamics (CFD) software suite, the study incorporates detailed crankshaft rotational kinematics and piston reciprocation to accurately model oil drawdown and retention across various operational conditions. A Volume of Fluid (VOF) approach is applied to assess the impact of crankshaft rotational speeds of 5000 rpm and 6500 rpm on oil distribution and aeration in the oil pan. Comprehensive computational analyses characterize oil-air distribution patterns, quantify oil flow rates through drainback pipes, and elucidate bubble formation dynamics within the sump. The study also examines the relative contributions of crankshaft rotation, piston pumping, and balance
Godavarthi, Raghu VamseeChen, Yung-MingPandey, AshutoshSrinivasan, Chiranth
Large-bore gas SI ICEs are supposed to operate under more strict conditions in terms of NOx level and potentially using new generation of fuels (e.g., hydrogen, ammonia) in the near future. Currently, the TA Luft norm is being considered while typical BMEP levels are between 22-28 bar. It is expected that NOx will have to drop significantly (down to 20% or even below 10% of the amount based on TA Luft) while engine BMEP is supposed to be increased above 30 bar. The paper is based on 0-D/1-D simulations while using the experience gained from older research projects concerning similar engines. The main goal is to study the influence of different operating conditions (e.g., NOx level, BMEP level, control means, ambient conditions) on both ICE performance and turbocharger operation while comparing classical 2-stage system with 2 electrically assisted ones (e-turbo, e-booster) – steady state performance is of the main focus while transient one is also considered. Complex optimizations were
Vitek, OldrichMacek, JanMares, BohumilKlima, JiriVacek, Martin
Conversion to hydrogen of automobile internal combustion engines powered by fuels of petroleum origin is the most important direction for solving environmental, energy and climate problems of modern civilization. A number of researchers, based on experimental studies, note the presence of a phenomenon of a significant increase in heat losses in hydrogen engines compared to gasoline engines. This phenomenon is explained by an increase in temperature and speed of movement of the working fluid. In this paper, it is shown that the main reason for the increase in thermal losses is the ability of the hydrogen flame to penetrate into the narrow gap between the piston and the engine sleeve. This problem has not been discussed in engine theory before. D mathematical modeling of flame penetration and extinguishing processes in the specified gap of a hydrogen engine (D/S=86/86 mm/mm, Ne=60 kW, n=5500 min-1) was carried out. Critical gap sizes for various fuels have been established, heat transfer
Kavtaradze, RevazNatriashvili, TamazGladyshev, Sergey
Methanol can be produced renewably and used in compression ignition (CI) engines as a replacement for fossil diesel. However, methanol is a low cetane fuel, creating challenges in achieving stable operation, particularly at low load. One potential solution is through surface ignition via a glow plug. In this work, experiments were conducted on a methanol-fueled 2.1 L single cylinder engine instrumented with a glow plug. The engine was designed for alcohol combustion with an elevated compression ratio (26:1) and a narrow injector umbrella angle (120 degrees) compared to standard diesel compression ignition hardware. As such, no plume was directly intercepted by the glow plug. A representative low load case of two conventional mixing controlled compression ignition (MCCI) strategies (single injection and pilot-main) and three kinetically controlled advanced CI strategies (homogenous charge compression ignition, split injection, partially premixed combustion) were tested with and without
Gainey, BrianSvensson, MagnusVerhelst, SebastianTuner, Martin
In cogeneration system, the pre-chamber natural gas engine adopts combustion technologies such as ultra-high supercharged lean burn and Miller cycle to increase the theoretical efficiency by increasing the specific heat ratio and the mechanical efficiency by improving the specific power. In recent years, the use of hydrogen fuel has been attracting attention in order to achieve carbon neutrality, and it is required to operate existing high-efficiency natural gas engines by appropriately mixing hydrogen. For this purpose, it is important to have natural gas and hydrogen co-combustion technology that allows combustion at any mixture ratio without major modifications. The authors mixed hydrogen into the fuel of an ultra-high supercharged lean burn pre-chamber natural gas engine (Bore size: 200mm) that has already achieved high efficiency and performed combustion experiments at BMEP (Brake mean effective pressure) of 2 MPa or more. The engine load and hydrogen mixture ratio were used as
Morikawa, KojiKimura, ShinSakai, ShunyaMoriyoshi, Yasuo
This paper explains transient, computationally rigorous, three-dimensional and one-dimensional multiphase CFD analysis of engine oil drainback system and lubrication system for predicting aeration. Aeration of engine oil is an important factor as it affects working of Hydraulic Lash Adjusters, bearings performance and it reduces lube system pressure itself which is detrimental for the entire engine. In this work specifically effect of engine tilting on lube oil aeration is presented. When engine is tilted, crankshaft and connecting rod/s are dipped in to oil, which creates air bubbles. These air bubbles travel to lube pump and then to the engine lube system. Therefore, it is essential to model aeration in Engine crankcase, Oil pan and Lube system for the purpose of predicting oil pressure reduction in lube system. The problem under consideration is spread over a bigger zone, involves rotating and translating components, passage’s dimensions are varying from microns to meters and
Tawar, Ranjit RamchandraBedekar, Sanjeev
The paper illustrates the process and steps in the development of a neural network-based economic Model Predictive Control (MPC) strategy for reducing diesel engine feed gas emissions. This MPC controller performs fuel limiting and modifies intake manifold pressure and exhaust gas recirculation (EGR) rate set-points to the inner loop air path controller to reduce engine-out oxides of nitrogen (NOx) and Soot emissions. We examine two Recurrent Neural Network (RNN) options for a control-oriented emissions model which are based on a multi-layer perception (MLP) architecture and a long short-term memory (LSTM) architecture. These RNN models are trained for use as prediction models in MPC. Both models are defined in input-output form, assuming that measurements/estimates of current values of NOx and Soot are available. We discuss and compare their training using PyTorch. The formulation of economic MPC is detailed, including the definition of the cost function and soft constraints
Zhang, JiadiLi, XiaoKolmanovsky, IlyaTsutsumi, MunecikaNakada, Hayato
In order to reduce the environmental impact of transportation, the adoption of low and zero carbon fuel is needed to reduce the greenhouse gas emissions from engines, both from tailpipe and well-to-wheel perspectives. However, for some of the promising fuels, such as renewable natural gas and ammonia, the relatively low chemical reactivity and laminar flame speed bring challenge to a rapid and efficient combustion process, especially under lean or diluted conditions to suppress NOx emissions, leading to reduced combustion and thermal efficiencies. To tackle the challenge, high in-cylinder flow speed is needed to shorten the combustion duration, together with strong ignition sources to support the initial flame kernel development. In this paper, an ignition energy modulation system is developed to enhance both discharge current and discharge energy of a spark event to secure the ignition process. Moreover, a rapid compression machine is employed to compress the fuel-air mixture to the
Jin, LongYu, XiaoZhou, QingReader, GrahamLi, LiguangZheng, Ming
In hydrogen-fueled internal combustion engine (H2ICE), there are some ways to reduce nitrogen oxides (NOx) emissions. Using the wide flammability range of hydrogen, such as conducting lean combustion to reduce nitrogen oxides and employing exhaust gas recirculation (EGR), have been adopted. However, challenges exist in terms of load expansion, and due to the absence of high heat capacity of carbon dioxides in the exhaust, EGR also struggles to exhibit significant effects. In such a scenario, there is growing interest in injecting water into the H2ICE as an alternative to augment the EGR effect. In this study, the spark ignition (SI) single-cylinder engine equipped with two direct injectors was used to evaluate the hydrogen and the water dual direct injection combustion system. This system involved the direct injection of hydrogen using a wall-guided gasoline direct injector and the direct injection of water into the combustion chamber using a diesel injector. This approach utilizes the
Kim, KiyeonLee, SeungilKim, SeungjaeLee, SeunghyunMin, KyoungdougOh, SechulSon, JongyoonLee, Jeongwoo
This study investigates the ignitability of hydrogen in an optical heavy-duty SI engine. While the ignition energy of hydrogen is exceptionally low, the high load and lean mixtures used in heavy-duty hydrogen engines lead to a high gas density, resulting in a much higher breakdown voltage than in light-duty SI engines. Spark plug wear is a concern, so there is a need to minimise the spark energy while maintaining combustion stability, even at challenging conditions for ignition. This work consists of a two-stage experimental study performed in an optical engine. In the first part, we mapped the combustion stability and frequency of misfires with two different ignition systems: a DC inductive discharge ignition system, and a closed-loop controlled capacitive AC system. The equivalence ratio and dwell time were varied for the inductive system while the capacitive system instead varied spark duration and spark current in addition to equivalence ratio. A key finding was that spark energy
Hallstadius, PeterSaha, AnupamSridhara, AravindAndersson, Öivind
Noise pollution is a significant concern for global automotive industries which propels engineers to evolve new methods to meet passenger comfort and regulatory requirements. The primary purpose of an intake manifold in an automotive vehicle is to allow the passage of clean air for combustion and reduce the noise generated due to engine pulsations. This work proposes a Design for Six Sigma (DFSS) approach to optimize the intake manifold for better acoustic performance without compromising performance for a 3.6 L four-stroke engine for a Plug-in Hybrid electric vehicle (PHEV). Conventionally, intake manifold design has been an iterative process. It involves repetitive testing to arrive at an optimum design. The intake manifold must be designed for better acoustics and engine performance, complicating the design process even more. The DFSS approach has input, output, control, and noise factors. Air-borne noise coming from the engine at different speeds is the input, and the throttle body
Dixit, Manish
This study experimentally investigates the liquid jet breakup process in a vaporizer of a microturbine combustion chamber under equivalent operating conditions, including temperature and air mass flow rate. A high-speed camera experimental system, coupled with an image processing code, was developed to analyze the jet breakup length. The fuel jet is centrally positioned in a vaporizer with an inner diameter of 8mm. Airflow enters the vaporizer at controlled pressures, while thermal conditions are maintained between 298 K and 373 K using a PID-controlled heating system. The liquid is supplied through a jet with a 0.4 mm inner diameter, with a range of Reynolds numbers (Reliq = 2300÷3400), and aerodynamic Weber numbers (Weg = 4÷10), corresponding to the membrane and/or fiber breakup modes of the liquid jet. Based on the results of jet breakup length, a new model has been developed to complement flow regimes by low Weber and Reynolds numbers. The analysis of droplet size distribution
Ha, NguyenQuan, NguyenManh, VuPham, Phuong Xuan
The adoption of hydrogen as a sustainable replacement for fossil fuels is pushing the development of internal combustion engines (ICEs) to overcome the technical limitations related to its usage. Focusing on the fuel injector in a DI configuration, it must guarantee several targets such as the adequate delivery of hydrogen mass for the given operating condition and the proper mixture formation in the combustion chamber playing a primary role in reaching the target performance in H2-ICEs. Experimental campaigns and computational fluid dynamics simulations can be used as complementary tools to provide a deep understanding of the injector behaviour and to drive design modifications in a quick and effective way. In the present work an outward opening, piezo-actuated injector purposely designed to be fuelled with hydrogen is tested on several operating conditions to evaluate its performance in terms of delivered mass flow and jet morphology using the Schlieren imaging technique. To
Pavan, NicolòCicalese, GiuseppeGestri, LucaFontanesi, StefanoBreda, SebastianoMechi, MarcoVongher, SaraPostrioti, LucioBuitoni, GiacomoMartino, Manuel
This research experimentally investigates the spray vaporization of high-pressure dimethyl ether (DME) using a single-hole research injector focusing on nominal operating conditions from the Engine Combustion Network (ECN). DME is a synthetic alternative to diesel fuel, offering both high reactivity and potential reductions in particulate emissions. Because DME only features half of the energy density of diesel fuel, a specifically designed fuel system with a high mass flow rate to meet the energy delivery requirements is needed. The unique physical properties of DME, including higher vapor pressure and lower viscosity, introduce challenges like cavitation and unique evaporation characteristics that deviate from typical diesel fuel. These features are likely to lead to differences in fuel mixing and combustion. This study aims to provide detailed experimental data on DME spray characteristics under engine-like conditions, helping the development of predictive CFD models for optimal
Yi, JunghwaWan, KevinPickett, LyleManin, Julien
Honda Motor Corporation has developed a new naturally aspirated in-line 4-cylinder direct injection gasoline engine for C segment sedans that combines high environmental performance and power output. Development time and cost were greatly reduced by utilizing basic structures and components that had previously been developed engine for hybrid vehicles. In addition to the environmental performance at which hybrid engines excel, the driving performance required from a pure gasoline engine for C segment sedans with a low environmental impact was aimed to achieve by optimizing the shape of the combustion chamber to obtain rapid combustion, adjusting intake and exhaust valve timing, employing fuel injection control and adopting a two-piece water jacket that protects the exhaust system component by lowering the exhaust gas temperature at high load. As a result, the newly developed engine achieves a maximum thermal efficiency of 40% with knock suppression effect through rapid combustion
Kondo, TakashiOhmori, TakeyukiYamamoto, JunpeiMiki, Kentaro
Direct injection (DI) hydrogen internal combustion engines are gaining attention as a promising technology for a sustainable energy transition, particularly in the transport sector. A key factor in improving the performance of these engines is understanding how hydrogen jets behave within the combustion chamber, especially their interactions with the chamber walls. These jet-wall interactions are critical since they have a major influence on fuel-air mixing which directly affects combustion efficiency and emissions. This study investigates the behavior of high-velocity hydrogen jets formed after exiting the injector. These jets propagate through surrounding air and interact with wall surfaces. When they impinge on wall surfaces, they undergo various processes such as radial spreading outward along the wall surface, mixing, and diffusion. These processes are influenced by factors including pressure ratio (PR) - the ratio between injection pressure and chamber pressure - and the geometry
Gong, MiaoxinLundgren, MarcusEismark, JanAndersson, Mats
This paper explores the potential of leveraging methanol's knock-resistant properties to facilitate both dual fuel (DF) and spark ignition (SI) operation in retrofitted heavy-duty (HD), high-speed marine engines. The study involves retrofitting an original 6-cylinder 7.15L CI diesel engine with port fuel injection (PFI) of methanol to enable DF operation. Later, the diesel injectors were replaced with six spark plugs allowing SI operation. Notably, efforts were made to minimize adaptations to the existing diesel engine, maintaining the compression ratio (CR) at 17.6:1 and retaining the same turbocharging pressure. This research aims to assess the feasibility of retrofitting conventional HD diesel engines (high CR, large bore) for dual-fuel and SI operation on methanol, with a focus on optimizing engine performance, while preserving key characteristics for HD applications, e.g. high torque and high power density. The high CR required spark retarding to prevent knock at higher loads in
Dejaegere, QuintenBallerini, AlbertoDemiddeleer, SheldonVanderbeken, ThomasBracke, KwintenGyselinck, BenD'Errico, GianlucaVerhelst, Sebastian
There is a need to reduce both the greenhouse gas emissions of internal combustion engines, and the reliance on traditional fossil fuels like Ultra Low Sulfur Diesel (ULSD). In this research, a synthetic paraffinic kerosene fuel, designated S8 and created from natural gas feedstocks using the Fischer-Tropsch process was investigated to determine its autoignition and combustion characteristics, emissions, and tribological properties. This fuel, S8, was found to have a Derived Cetane Number (DCN) of 62, which reflects a shorter Ignition Delay (ID), and Combustion Delay (CD) compared to ULSD, which has a DCN of 48. However, due to the chemical properties of S8, it lacks sufficient lubrication qualities in comparison to ULSD, so addition of 3% methyl oleate by mass was used to improve lubricity. The shorter ignition delay of S8, initially observed in a Constant Volume Combustion Chamber (CVCC) and confirmed in a fired Common Rail Direct Injection (CRDI) experimental engine. Investigations
Soloiu, ValentinWillis, JamesNorton, ColemanDavis, ZacharyGraham, TristanNobis, Austin
Hydrogen is a viable option to power high-performance internal combustion engines while reducing pollutant emissions thanks to its high lower heating value (LHV) and fast combustion rate. Furthermore, if compared to gasoline, hydrogen is characterized by a higher ignition delay time, which makes it more knock-resistant under the same thermodynamic conditions. In this paper, hydrogen potential as a fuel in a high-performance PFI naturally aspirated engine under stoichiometric conditions and high load regimes is investigated through zero and three-dimensional simulations. The analyses show that a stoichiometric hydrogen mixture reaches higher pressure and temperature values during compression than iso-octane at the same operating conditions, hence limiting the maximum engine compression ratio to avoid undesired ignitions throughout the combustion process. Additionally, hydrogen low density causes a reduction in terms of trapped energy inside the cylinder. Thus, despite its LHV is almost
Madia, ManuelVaccari, MarcoDalseno, LucaCicalese, GiuseppeCorrigan, DaireVilla, DavideFontanesi, StefanoBreda, Sebastiano
A multi-dimensional model of the spark ignition process for SI engines was developed as a user-defined function (UDF) integrated into the commercial engine simulation software CONVERGE CFD. The model presented in this paper simulates energy deposition from the ignition circuit into the fuel-air mixture inside the cylinder. The model is based on interaction and collision between electrons in the plasma arc and the gas molecules inside the cylinder using parameters from the ignition circuit and gas inside the cylinder. Full engine simulations using CONVERGE CFD with the developed ignition model including the ignition circuit model, arc propagation model, and energy deposition model were performed to evaluate the validity and performance of the model and to compare with the ignition model provided by CONVERGE CFD. A low turbulent port fuel injected single-cylinder CFR engine was used for comparison. Continuous multi-cycle RANS simulations showed cycle-to-cycle variations. The range of the
Kim, KyeongminHall, MatthewJoshi, SachinMatthews, Ron
Two 50-hr engine dynamometer tests were conducted on 12-cylinder diesel military engines with differing piston ring sets. Engine A exhibited more than double the oil consumption over engine B. An investigation was conducted to explain why the oil consumption differed by employing several posttest analytical techniques including cylinder bore geometry measurements, surface metrology, wear characterization, and chemical analysis on the piston rings and cylinder wall coatings. The 3D colormaps of cylinder bore deformation showed uneven volumetric deformation through the piston stroke instead of 2D plane deformation. It was found that the primary reason of high oil consumption was direct loss of sealing between the piston, piston ring and cylinder bore due to predominately abrasive wear, three-body abrasive wear and bore polishing. Furthermore, the compromised sealing of the combustion chamber led to blow-by. Carbon deposits, corrosive byproducts, surface abrasives, loss of desired surface
Thrush, StevenChen, AijieFoley, MichaelSebeck, KatherineBoufakhreddine, Ziad
The impact of injection pressure on a split-injection energy-assisted compression-ignition (EACI) combustion strategy was studied in an optically accessible engine with a custom ribbed piston bowl design. Three injection pressures (600, 800, and 1000 bar) were investigated for three split-injection dwells (1.5, 2.0, and 2.5 ms) with a fixed second injection timing of -5.0 CAD. The Gaussian-shaped ribbed piston bowl design was employed to position hot combustion gases from the first injection near the centrally located injector to enable rapid ignition and mixing-controlled combustion of the second injection. At 600-bar injection pressure, as injection dwell was shortened, relocation of hot combustion gases near the injector became increasingly more difficult due to less available time for relocation and due to the higher in-cylinder densities at the start-of-injection (SOI) for the first injection. Increased injection pressure (800 and 1000 bar) improved the relocation of the first
Amezcua, EriStafford, JacobKim, KennethKweon, Chol-BumRothamer, David
A glow plug is generally used to assist the starting of diesel engines in cold weather condition. Low ambient temperature makes the starting of diesel engine difficult because the engine block acts as a heat sink by absorbing the heat of compression. Hence, the air-fuel mixture at the combustion chamber is not capable of self-ignition based on air compression only. Diesel engines do not need any starting aid in general but in such scenarios, glow plug ensures reliable starting in all weather conditions. Glow plug is actually a heating device with high electrical resistance, which heats up rapidly when electrified. The high surface temperature of glow plug generates a heat flux and helps in igniting the fuel even when the engine is insufficiently hot for normal operation. Durability concerns have been observed in ceramic glow plugs during testing phases because of crack formation. Root cause analysis is performed in this study to understand the probable reasons behind cracking of the
Karmakar, NilankanOrban, Hatem
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