Browse Topic: Engine components

Items (22,675)
A great number of performances of an electric vehicle such as driving range, powering performance, and the like are affected by its configured batteries. Having a good grasp of the electrical and thermal behavior of the battery before the detailed design stage is indispensable. This paper introduces an experiment characterization method of a lithium-ion battery with a coolant system from cell level to pack level in different ambient conditions. Corresponding cell and pack simulation models established in AMESim that aimed to capture the electrical and thermal features of the battery were also illustrated, respectively. First, the capacity test and hybrid pulse power characterization (HPPC) test were conducted in a thermotank to acquire basic data about the battery cell. Next, based on acquired data, first-order equivalent circuit model (1C-ECM) was built for the battery cell and further combined with environmental boundary conditions to check the simulation accuracy. Then, hybrid
Zhou, ShuaiLiu, HuaijuYu, HuiliYan, XuYan, Junjie
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
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
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
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
In direct injected engines the spray formation is important for both combustion performance and emission formation. Thus, being able to compare how the spray formation is affected by changes in nozzle design, injection pressure or fuel formulation is an important area of research for all engine sizes. This becomes especially important for the introduction of new sustainable fuels, or for fuel injection optimization to increase efficiencies and minimize the formation of emissions such as particles. High-speed imaging of the fuel spray using the schlieren technique is well established for this purpose, and the Engine Combustion Network (ECN) has developed multiple guidelines to ensure that a similar experimental approach is used in different laboratories around the world. For the initial image processing, the ECN provides a procedure based on an image-temporal-derivative approach. Many researchers however rely on intensity-based thresholding, preceded by contrast adjustment, background
Sileghem, VictorLarsson, TaraDejaegere, QuintenVerhelst, Sebastian
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
The significant mechanical features of aluminum alloy, including cost-effectiveness, lightweight, durability, high reliability, and easy maintenance, have made it an essential component of the automobile industry. Automobile parts including fuel tanks, cylinder heads, intake manifolds, brake elements, and engine blocks are made of aluminum alloy. The primary causes of its engineering failure are fatigue and fracture. Aluminum alloys' fatigue resistance is frequently increased by surface strengthening methods like ultrasonic shot peening (USP). This article discusses the shot peening dynamics analysis and the influence of ultrasonic shot peening parameters on material surface modification using the DEM-FEM coupling method. Firstly, the projectile motion characteristics under different processes are simulated and analyzed by EDEM. The projectile dynamics characteristics are imported into Ansys software to realize DEM-FEM coupling analysis, and the surface modification characteristics of
Adeel, MuhammadAzeem, NaqashXue, HongqianHussain, Muzammil
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
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
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 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
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.
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
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
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
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
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
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
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
This study investigates the impact of thermal imbalances on energy delivery and Battery State of Power (SoP) in immersion-cooled battery cells. It explores how these imbalances, which arise when cells within a module operate at different temperatures, lead to variations in internal resistance and inefficiencies in energy storage and discharge. Such imbalances critically affect the battery's SoP, representing the maximum charge or discharge power the system can support over specific time intervals. By analyzing SoP over 10-second durations and continuous, we assess how thermal imbalances influence both short-term and medium-term power capabilities. Temperature significantly impacts cell aging, and imbalances can accelerate degradation in some cells, ultimately affecting serviceability. To address these issues, we employ a high-level simulation framework that integrates advanced tools. GT-SUITE software optimizes thermal performance by adjusting coolant temperature and flow rate to
Meshginqalam, AtaNegro, SergioAtluri, PrasadTyagi, RamavtarSuzuki, JorgeK B, AnjushaCao, Yuyuan
When the cooling fan of the commercial vehicle engine is working, there is a strong fluid-structure interaction (FSI) between the airflow and the blades. If the effect of this interaction is not considered, significant errors may be caused in the prediction of fan performance. To analyze the effect of FSI on the aerodynamic and structural performance of the cooling fan, calculation models with and without considering FSI were established. The pressure and efficiency of the cooling fan were calculated using three methods: the Multiple Reference Frame (MRF) method, the Sliding Mesh (SM) method, and the bidirectional FSI method. These results were then compared with test data. Based on the FSI method, the aerodynamic and structural performance of the fan at different flow rates, rotational speeds and temperatures were calculated, and compared with results if FSI is ignored. The effect of flow rate, rotational speed and temperature on the fan performance was analyzed. The comparison and
Yu, HuiYin, ZhihongYing, RunhaiWang, XinlingDuan, YaolongShangguan, Wenbin
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
Proton exchange membrane fuel cell (PEMFC) is widely used in transportation and high-efficiency energy systems for their high power density and rapid start-up capability. The temperature control of its thermal management system is characterized by slow response and system oscillation, and the temperature control process suffers from problems such as large temperature fluctuations and slow temperature rise during cold starts. To effectively control the fuel cell thermal management system, this paper proposes a fuzzy PID-based control strategy to optimize the temperature control of the stack by comprehensively controlling the cooling fan, thermostat, temperature control valve, and heat components. By modeling the 60kW PEMFC thermal management system on the MATLAB/Simulink platform, the flow distribution and heat exchange of each component are analyzed and the optimized fuzzy control strategy is compared with the traditional PID control strategy. The simulation results show that the
Zhang, YilongZhang, YunqingGuo, JunWu, Jinglai
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
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
Taking a certain type of diesel engine turbocharger as the research object, a detailed study on the identification of turbocharger surge based on non-intrusive acoustic signals was conducted, and a novel turbocharger surge identification method based on multi-domain composite features of acoustic signals was proposed. The data related to the acoustic signals were collected through a series of supercharger surge reproduction experiments, and subsequently, a comprehensive database of these acoustic signals was established. Based on the multi-domain perspective of the time domain and frequency domain, 35 specific features were selected and extracted; the contribution of each individual feature to the occurrence of wheezing was calculated using the random forest algorithm, and the core contributing features were selected to be combined into a comprehensive multi-domain composite feature. This composite feature was then used for the recognition of turbocharger surge, serving as a highly
Zhu, JiaxuZheng, HongyuZong, Changfu
During engine idling, the low engine speed, typically from 600 rpm to 800 rpm, together with the low throttle opening angle, makes it challenging for a proper fuel air mixing process. The uneven intake charge distribution and high portion of internal EGR because of the inefficient gas exchange process further make the air fuel ratio unstable, which is challenging for a robust ignition and combustion process. In this paper, the challenge of achieving proper combustion phasing while maintaining acceptable combustion stability is investigated, and a specially designed common-coil pack was utilized to improve engine idling performance by supplying prolonged ignition duration and elevated discharge current amplitude. The common-coil pack, which comprises three parallel connected ignition coils, was shared by all 4 cylinders of the engine. The ignition strategy shows the capability to advance the combustion phasing for higher IMEP output, while maintaining the combustion stability, and
Yu, XiaoChen, GuangyunQian, JinLeblanc, SimonWang, LinyanZheng, Ming
In our laboratory, the focusing compression principle has been proposed, which is based on pulsed multi-jets of gas colliding around the chamber center. This aims to reduce the cooling loss on the chamber wall and the exhaust loss and improve the thermal efficiency. Our past studies focused on gasoline combustion experiments using the engine with the principle and suggested that the engine had the potential to achieve high thermal efficiency and knock resistance. Considering these past results and the growing interest in carbon-free fuels for net zero, in this paper, fundamental experimental evaluations of hydrogen combustion were principally conducted using the same engine with the focusing compression principle. The air was injected toward the chamber center from seven intake nozzles, while hydrogen gas was supplied from one intake nozzle, respectively. Hydrogen was injected with a relatively low pressure of 50 kPaG. This means that an injector with high injection pressure was not
Yamada, SotaNaitoh, KenBaba, ShotaroUkegawa, HirakuNishizawa, TomohikoYatabe, Atsuhiro
Sound pollution has become one of the major environmental concerns for the global automotive industry. Air Induction System (AIS) plays an important role in engine performance and vehicle noise. An ideal design of AIS provides debris-free air for combustion and reduces the engine noise that is heard while snorkeling. This work aims to correlate low-frequency engine order noise prediction at the compressor inlet and snorkel inlet for a 2.0L I4 turbo engine of a Plug-in hybrid vehicle (PHEV) for better acoustic performance without compromising on engine performance. 1D simulation software GT-POWER, Simcenter 3D, and Hypermesh are used for this work. Transmission loss (TL) results with respect to the frequency of the air-box with ducts and intake manifold with charge air cooler are plotted from 0 to 1000 Hz. The air intake system TL results show a good correlation between 3D and 1D till 600 Hz. Compressor and snorkel noise simulation results, especially the firing order and its harmonic
Dixit, Manish
The paper presents novel studies on the electrical-to-thermal energy deposition to gas at different phases of a spark. The experiments utilized a 10.9 milliliter custom-built spark calorimeter. The energy transfer efficiencies across spark phases—breakdown+arc, and glow are quantified, emphasizing their importances in ensuring robust ignition. An AC capacitive ignition system was considered in the experiments. The spark plugs used in the experiments were of dual-nickel standard J-gap design of a fixed electrode gap. Test results show the breakdown+arc phases are highly efficient in converting electrical to thermal energy, crucial for ignition. The glow phase, offering control flexibility, is found to be less effective in energy transfer from spark to gas. In addition, a maximum threshold for both glow current and duration is found. Exceeding the threshold reduces the net energy deposition to the gas, indicating an increase in thermal energy losses, primarily to the spark plug
Saha, AnupamTunestal, PerAengeby, JakobAndersson, Oivind
Achieving stable HCCI combustion requires specific in-cylinder boundary conditions. Trace residual species, such as nitric oxide (NO), can have an impact on the reactivity, and thus the combustion stability, of different fuels in HCCI. This study investigates the effects of nitric oxide (NO) on the reactivity and combustion stability of ethanol and gasoline in a single-cylinder HCCI engine. The promoting and inhibiting impact of NO on iso-octane’s ignition delay time are available in the literature; nevertheless, as a baseline study, these effects on the autoignition of gasoline were documented in this work. For ethanol, the NOx concentration seeded in the intake air varied from 0-1000 ppm while maintaining a constant combustion phasing (CA50 at 7.5 CAD) and a global equivalence ratio of 0.34. Ethanol exhibited a linear reduction in intake temperature, decreasing by 47 K with 927 ppm NO. For gasoline, a 225-ppm increase in NO reduced the intake temperature required for HCCI by 40 K
Bhatt, AnkurGandolfo, JohnVedpathak, KunalLawler, BenjaminGainey, Brian
Pre-chamber (PC) technology has demonstrated its capability to achieve clean and stable combustion in internal combustion engines (ICEs) under lean conditions. This study evaluates the effectiveness of PC in direct injection (DI) hydrogen (H2)-ICEs compared to conventional spark ignition (SI) operation using high-fidelity computational fluid dynamics simulations across a range of load conditions. Various loads were attained by systematically adjusting intake pressure and injected H2 mass. The primary hypothesis posits that highly turbulent PC jets facilitate rapid mixing and combustion of ultra-lean mixtures. The comparative analysis revealed that DI fueling in both PC and SI modes did not achieve perfectly homogeneous mixtures, particularly under high load conditions, although PC slightly enhanced mixture uniformity. Combustion behavior exhibited a non-monotonic trend, with SI outperforming PC at low and high loads, while PC demonstrated superior performance at medium loads despite
Menaca, RafaelLiu, XinleiMohan, BalajiCenker, EmreAlRamadan, AbdullahIm, Hong
Fuel cells offer several advantages, including extended range, rapid refueling, and clean and efficient, making them well-suited for long-distance transportation in commercial vehicles. A multi-objective real-time optimization energy management strategy is proposed based on the comprehensive consideration of the equivalent hydrogen consumption and energy source lifetime. Power distribution among the energy sources is achieved by minimizing the vehicle's instantaneous comprehensive operational cost. Two coefficients are employed to restrict the fuel cell's start-stop frequency and load variation range. Additionally, two control coefficients are introduced in the objective function to regulate the battery's state of charge. The analysis shows that multi-objective real-time optimization energy management strategy is 10% and 14% less economical than conventional rule-based energy management strategy in both operating conditions and 5% and 7.8% higher than dynamic programming. However, the
You, JianhuiGu, ZhuangzhuangWu, JinglaiZhang, Yunqing
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.
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
Reduction of frictional losses by changing the surface roughness in the form of surface textures has been reported as an effective method in reducing friction in the boundary regime of lubrication. Laser-based micro texturing has been mostly used to create these texture patterns and it is reported that it can reduce the frictional resistance by ~20-50%. However, the use of laser-based techniques for texture preparation led to residual thermal stress and micro cracks on the surfaces. Hence, the current study emphasizes using conventional micromachining on piston material (Al alloy Al4032) to overcome this limitation. Three variations of semi-hemispherical geometries were prepared on the surface of Al alloy with dimple depths of 15, 20 and 40 μm and dimple diameters of 90, 120 and 240 μm. Prepared textured surfaces with untextured surfaces are compared in terms of wear, wettability, and friction characteristics based on Stribeck curve behaviors. Results of this investigation demonstrated
Sahu, Vikas KumarShukla, Pravesh ChandraGangopadhyay, Soumya
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
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
A methodology for optimizing natural properties of a powertrain for an electric vehicle has been presented. A model with six-degree-of-freedom was proposed utilizing ADAMS, and the natural frequencies and energy distribution of the powertrain are estimated using the proposed model. The calculated natural frequencies and energy distribution shown that the initial design of mount stiffness does not meet requirements of natural frequency and decoupling ratio, and vibration isolation standards. To overcome the limitations of conventional optimization techniques, a non-dominated sorting genetic algorithm (NSGA) was adopted for the enhancement optimization the mounts parameters. The optimization objectives included the refinement of the decoupling rates and frequency distribution at all mounting directions. Stiffness parameters of the mounts were optimized via the NSGA. The optimized results confirmed significant improvements for powertrain natural characteristics. This study presented an
Jin, YangLi, DeweiZhao, YangXiao, LeiGuo, Yiming
Lithium-ion batteries (LIBs) are critical components in electric vehicles (EVs) and renewable energy systems. However, conventional cooling techniques for LIBs often struggle to efficiently dissipate heat during fast charging and discharging, potentially compromising performance and safety. This study investigates the thermal performance of immersion cooling applied to an Electric Vehicle (EV) battery module comprised of NCA-chemistry-based cylindrical 21700 format Lithium-ion cells. The effectiveness of immersion cooling in reducing maximum cell temperature, temperature gradient, cell-to-cell temperature differential, and pressure drop within the battery module is evaluated on a detailed 3D model of a 360-cell immersion-cooled battery module that was developed, incorporating a well-established heat generation model based on theoretical analysis and experimental data to simulate the thermal characteristics of the battery system. The effects of the different fluid properties are first
Garcia, AntonioMicó, CarlosMarco-Gimeno, JavierElkourchi, Imad
In a conventional cam-based valve actuation system, the valve events are tied up with the rotation of the crankshaft. In contrast, the electronic variable valve actuation (VVA) system enables flexible control of valve events independent of the crankshaft rotation. The present article discusses the development and control system design of a single-acting electro-pneumatic variable valve actuation (EPVVA) system that can be retrofitted to a conventional SI engine. The EPVVA system utilizes fast switching solenoid valves which modulate the flow of pressurized air in and out of a pneumatic chamber. The control system design is conducted in MATLAB Simulink platform using model-based approach. The valve actuator model is formulated such that it simulates the trajectory of the motion of the engine valve by numerically integrating a set of coupled differential equations that govern the thermo-fluid-dynamics and applied mechanics aspects of the valve actuation of the EPVVA system. The timings
Satalagaon, Ajay KumarGuha, AbhijitSrivastava, Dhananjay Kumar
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
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
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
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
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