Browse Topic: Internal combustion engines

Items (19,123)
Increasing global pressure to reduce anthropogenic carbon emissions has inspired a transition from conventional petroleum-fueled internal combustion engines to alternative powertrains, including battery electric vehicles (EVs) and hybrids. Hybrids offer a promising solution for emissions reduction by addressing the limitations of pure EVs such as slow recharge and range anxiety. In a previous research endeavor, a prototype high-power density generator was meticulously designed, fabricated, and subjected to testing. This generator incorporated a compact permanent magnet brushless dynamo and a diminutive single-cylinder two-stroke engine with low-technology constructions. This prototype generated 8.5 kW of electrical power while maintaining a lightweight profile at 21 kg. This study investigates the performance and emissions reduction potential by adapting the prototype to operate on methanol fuel. Performance and emissions were experimentally evaluated under varying operating conditions
Gore, MattNonavinakere Vinod, KaushikFang, Tiegang
Diesel combustion is a highly heterogeneous process in which the fuel must undergo several sub-processes after injection in order to release its heat through combustion. Prior to evaporation, computational fluid dynamic (CFD) simulations track the injected fuel mass using a Lagrangian frame of reference to determine the pathlines of the liquid fuel in the gaseous environment. However, after evaporation, when the fuel mass becomes part of the working fluid, it is no longer tracked in a Lagrangian reference frame as it undergoes its mixing and combustion processes. To gain deeper insights into the diesel combustion process, a methodology is proposed to track the evolution of fuel mass packets while in the gaseous state attaining a Lagrangian-esque description of the fuel’s evolution. This is achieved using the commercially available capabilities in Convergent Science’s CFD package, without requiring user-defined functions. The methodology is applied to a heavy-duty diesel engine and
Gohn, JamesKumar, MohitGainey, BrianLawler, Benjamin
Fuel cell electric vehicles (FCEVs) are gaining increasing interest due to contributions to zero emissions and carbon neutrality. Thermal management of FCEVs is essential for fuel cell lifespan and vehicle driving performance, but there is a lack of specialized thermal balance test standards for FCEVs. Considering differences in heat generating mechanism between FCEVs and internal combustion engine vehicles (ICEVs), current thermal balance method for ICEVs should be amended to suit for FCHVs. This study discussed thermal balance performance of ICEV and FCHVs under various regulated test conditions based on thermal balance tests in wind tunnel of two FCEVs and an ICEV. FCEVs reported overheat risk during low-speed climbing test due to continuous large power output from fuel cell (FC). Frequent power source switches between FC and battery were observed under dual constrains of fuel cell temperature and battery state of charge (SOC). Significant temperature exceedance of ICEV occurred
Fang, YanhuaMin, YihangMing, ChenLi, HongtaoLi, DongshengHe, ChongMao, Zhifei
Controlling the combustion phasing of a multi-fuel compression ignition engine in varying ambient conditions, such as low temperature and pressure, is a challenging problem. Traditionally, engine control is achieved by performing experiments on the engine and building calibration maps. As the number of operating conditions increase, this becomes an arduous task, and model-based controllers have been used to overcome this challenge. While high-fidelity models accurately describe the combustion characteristics of an engine, their complexity limits their direct use for controller development. In recent years, data-driven models have gained much attention due to the available computation power and ease of model development. The accuracy of the developed models, which, in turn, dictates the controller’s performance, depends on the dataset used for building them. Several actuators are required to achieve reliable combustion across different operating conditions, and obtaining extensive
Govind Raju, Sathya AswathSun, ZongxuanKim, KennethKweon, Chol-Bum
Wankel rotary engines are renowned for having lower efficiency than classic reciprocating engines. One of the factors affecting the efficiency is an unfavourable surface area-to-volume ratio given by the particular geometry of the engine, which increases the heat loss during the combustion phase. A novel and specific study on this aspect was carried out in this work by implementing a general parametric routine in Octave/Matlab. It was able to compute the surface area-to-volume ratio and execute a sensitivity analysis on specific engine geometrical parameters (e.g. housing width “b”) in order to determine the geometrical configuration with the minimum surface area-to-volume ratio for a given swept volume, compression ratio and K factor (i.e. the ratio between generating radius and eccentricity). The aforementioned procedure was then applied considering the geometry of the Advanced Innovative Engineering 225CS rotary engine. Three virtual geometrical configurations with the same
Vorraro, GiovanniTurner, James
This work presents a computationally inexpensive but effective method for an initial assessment of component sizing and power-split for fuel cell hybrid electric heavy-duty trucks. As a first step, the proposed method employs a prototypical longitudinal vehicle model to generate power demand at every instant of a representative drive cycle. Subsequently, six fuel cell and battery sizing combinations, each providing a peak continuous system power of 400 kW, are identified based on drive cycle power demands, commercially available fuel cell sizes, and Department of Energy (DOE) sizing targets. Ultimately, for each sizing combination, a proportional-integral (PI) controller with anti-windup is implemented to split power between the fuel cell and battery. In this study, the controller is tuned to reduce hydrogen consumption while meeting the instantaneous power demand and maintaining the battery state-of-charge (SOC) between 0.3 and 0.7. The results indicate that increasing the fuel cell
Mandviwala, AliYesilyurt, SerhatStefanopoulou, Anna
This paper presents recent developments of the Euler/Lagrange wall film model which allow the efficient simulation of complete Selective Catalytic Reduction (SCR) systems, used for exhaust gas aftertreatment in diesel and newly designed H2 engines. Since release 2024R2, ANSYS Fluent is equipped with a chemistry model from recent literature to predict homogeneous chemical reactions in the film and heterogeneous reactions between gas and film occurring in SCR systems operating with aqueous urea solutions. The implementation of the chemistry model is first validated against results from Thermo–Gravimetric Analysis (TGA) measurements. The SCR–specific chemistry, combined with the Lagrangian Wall Film (LWF) model employing an improved wall–film convective heat transfer model, is then compared favorably with experimental SCR test rig measurements of urea deposits for fifty injection cycles, followed by a relaxation period. The full simulation completes significantly faster due to a new
Sofialidis, DimitriosMutyal, JayeshFaltsi, RanaBraun, MarkusBörnhorst, MarionEsch, Thomas
The majority of transportation systems continue to rely on internal combustion engines powered by fossil fuels. Heavy-duty applications, in particular, depend on diesel engines due to their high brake efficiency, power density, and robustness. Despite significant advancements in diesel engine technology that have reduced emissions and improved efficiency, complex and costly after-treatment systems remain necessary to meet the stringent emission regulations. Dimethyl ether (DME), which can be produced from various renewable feedstocks and possesses high chemical reactivity, is a promising alternative for heavy-duty applications, particularly in compression ignition direct injection engines. Its high reactivity, volatility, and oxygenated composition offer significant potential to address emission challenges while reducing reliance on after-treatment systems. However, DME’s lower energy density requires adjustments in injection parameters (such as injection pressure and duration) or
Cong, BinghaoLeblanc, SimonTjong, JimiTing, DavidYu, XiaoZheng, Ming
The Standard Test Method for Determination of Benzene, Toluene, and Total Aromatics in Finished Gasolines by Gas Chromatography/Mass Spectrometry, also known as ASTM D5769, identifies aromatic compounds ranging from carbon groups six to twelve (C6-C12). This method provides determination in less than 15 minutes of twenty-three target aromatics, quantification of uncalibrated Indans, as well as C10, C11, and C12 aromatics using extracted ions. In contrast, the Standard Test Method for Determination of Individual Components in Spark Ignition Engine Fuels by 100-MetreCapillary (with Precolumn) High-Resolution Gas Chromatography (ASTM D6730) offers a more comprehensive identification of compounds of multiple classes in gasoline samples also using a mass spectrometer (MS), focusing on aromatics from C6 to C14 for this research. This method uses a standard template of identified fuel components and corrects responses based on theoretical Flame Ionized Detector (FID) hydrocarbon responses
Dozier, JonathanGoralski, SarahGeng, PatReilly, Veronica
This paper investigates heated and cold Diesel Exhaust Fluid (DEF) sprays with the aim of establishing the effect of temperature on the resulting spray characteristics. The work is motivated by the need to optimize active Selective Catalytic Reduction (SCR) systems to meet more stringent nitrogen oxide (NOx) emission regulations for internal combustion engines. Pre-heating DEF has the potential to improve evaporation of the injected fluid, increasing the NOx conversion efficiency of the SCR at low exhaust temperatures. Experiments are carried out using the MAHLE SmartHeat fluid heater and mounted atop a DEF injector, with an incorporated thermocouple for fluid temperature. The fluid temperature established by the heater in this configuration was about 130 °C. The fluid is injected into an atmospheric environment and Schlieren imaging is used to visualize the spray evolution. CFD simulations are also carried out to validate the experimental observations and further shed light on the
Liu, ZeyangPeters, NathanBunce, MikePothuraju Subramanyam, SaiAkih Kumgeh, Benjamin
Electric vehicles (EVs) are particularly susceptible to high-frequency noise, with rubber eigenmodes significantly influencing these noise characteristics. Unlike internal combustion engine (ICE) vehicles, EVs experience pronounced variations in dynamic preload during torque rise, which are substantially higher. This dynamic preload variation can markedly impact the high-frequency behaviour of preloaded rubber bushings in their installed state. This study investigates the effects of preload and amplitude on the high-frequency dynamic performance of rubber bushings specifically designed for EV applications. These bushings are crucial for vibration isolation and noise reduction, with their role in noise, vibration, and harshness (NVH) management being more critical in EVs due to the absence of traditional engine noise. The experimental investigation examines how preload and excitation amplitude variations influence the dynamic stiffness, damping properties, and overall performance of
Hazra, SandipKhan, Arkadip Amitava
Toyota Motor Corporation pursuing an omnidirectional strategy that includes battery electric vehicle (BEV), plug-in hybrid electric vehicle (PHEV), and fuel cell electric vehicle (FCEV) to accelerate electrification. One of the technical challenges with our xEV batteries which feature good degradation resistance and long battery life, is that regenerative braking cannot be fully effective due to the decrease in regenerative power in some situations, such as low battery temperature. For the electrified vehicles with an internal combustion engine such as PHEVs, the solution has been running the engine to increase deceleration through engine braking during coasting. PHEVs are expected to extend their cruising range and enhance EV driving experience as "Practical BEVs". While increasing battery capacity and enhancing convenience, the restrictions on EV driving opportunity due to low battery temperature may negatively affect PHEV’s appealing. As an alternative, introducing a battery heater
Hoshino, Yu
In future spark-ignition internal combustion engines, characterized by high compression ratios, issues such as knocking and super-knocking have increasingly emerged as major factors limiting thermal efficiency improvements. Ion current detection technology, with its advantages of not altering engine structure, low cost, and maintenance-free operation, is considered as one of the most promising methods for in-cylinder combustion detection. However, the mechanism of ion current formation under end gas auto-ignition conditions remains unclear, and the matching law between the ion current signal and the combustion state can only be obtained by experimental and statistical methods so far, posing challenges for abnormal combustion diagnostics and control based on ion current detection technology. To analyze the signal characteristics of ion current under abnormal combustion from a more intrinsic perspective, this paper develops a one-dimensional flame ionization model using MATLAB. The model
Zhou, YanxiongDong, GuangyuNi, XiaociXu, JieLi, XianLi, Liguang
The rapid advancement of alternative energy and energy-saving technologies in China underscores the importance of conducting a comprehensive analysis of the total cost of ownership (TCO) for commercial vehicles such as buses and trucks. To address the challenges of quantifying time-sensitive and implicit costs, this study has developed an extensive database and a web-based modeling tool to evaluate the TCO of these vehicles for the period 2020–2040. The tool allows for user-customized inputs and generates TCO estimates across multiple technology evolution scenarios, encompassing nearly 200 vehicle types categorized by class, intended use, and powertrain technology, within diverse technology development pathways. The model integrates critical cost factors, including vehicle purchase costs, financing costs, energy expenditures, and inconvenience costs, providing a detailed assessment of long-term ownership costs. Key findings indicate that under the reference scenario, battery electric
Tan, XiaoluOu, Shiqi(Shawn)Wu, ShuhongChen, YongjianLin, Zhenhong
Prior study with biodiesel and its blends with ultra-low sulfur diesel (ULSD) and renewable diesel (RD) showed that a commercial diesel oxidation catalyst (DOC) is unable to effectively oxidize neat biodiesel (B100) or high-level biodiesel blends injected into the exhaust of a diesel engine at challenging conditions of low temperature, high exhaust flow rate and high dosing rate. In steady-state performance tests, the performance of blends up to B50 in ULSD or RD was nearly equivalent to ULSD at the lowest exhaust flow rate or for exhaust temperature over 340°C for medium and high flows. ULSD blends above 50 vol% biodiesel exhibited reduced thermal efficiency and DOC outlet temperature with increasing dosing rate and required exhaust temperatures over 400°C to achieve similar performance as ULSD. For RD blends at higher flow rates and temperatures below 300°C even B10 blends showed some loss in performance at the highest dosing rates. Data showed an increase in lightoff temperature
Lakkireddy, VenkataWeber, PhillipMcCormick, RobertHowell, Steve
Decarbonized or low carbon fuels, such as hydrogen/methane blends, can be used in internal combustion engines to support ambitious greenhouse gas (GHG) emission reduction goals worldwide, including achieving carbon neutrality by 2045. However, as the volumetric concentration of H2 in these fuel blends surpasses 30%, the in-cylinder flame propagation and combustion rates increase significantly, causing an unacceptable increase in nitrogen oxides (NOx) emissions, which is known to have substantial negative effects on human health and the environment. This rise in engine-out NOx emissions is a major concern, limiting the use of H2 fuels as a means to reduce GHG emissions from both mobile and stationary power generation engines. In this study, an experimental investigation of the combustion performance and emissions characteristics of a 4th generation Tour split-cycle engine was undertaken while operating on 100% methane and various hydrogen/methane fuel blends (30%, 40%, and 50% by volume
Bhanage, PratikCho, KukwonAnderson, BradleyKemmet, RyanTour, GiladAtkinson, ChrisTour, HugoTour, Oded
Under the background of the global dual carbon target, ammonia and hydrogen as the carbon-free fuel, have become a research hotspot for internal combustion engines. The existing researches mainly focus on the combustion characteristics influenced by equivalence ratio, hydrogen jet ignition and so on, while the relationship between combustion and emission characteristics should be also paid more attention. In this paper, the impact of combustion characteristic parameters on engine emissions is investigated by GT-power. The simulation model is based on a single cylinder engine with an active pre-chamber. Meanwhile, combustion characteristic parameters, in terms of CA50, combustion duration, CA10-CA50 and CA50-CA90 are set referred to the research of hydrogen jet ignition ammonia-hydrogen internal combustion engines. The results shown that there is compelling correlation between combustion parameters and specific emission profiles in ammonia-hydrogen internal combustion engines. Notably
Yuan, YangShang, QuanboDeng, JunLi, LiguangYin, XuemeiLai, HuilongMa, JiangliYu, FeiFeng, FengCui, HaoDu, Junchen
The use of internal combustion engine vehicles (ICEVs) and hybrid electric vehicles (HEVs) powered by biofuels produced by photosynthetic fixation of CO2 and synthetic fuels produced by industrial synthetic reactions can be an effective way to reduce well-to-wheel (WtW) greenhouse gas (GHG) emissions intensity from vehicles, including both new and legacy fleet. In this study, several lower-carbon intensity fuels that contain at least 50% of renewable components, have at least 40% lower carbon intensity compared to commercially available E10 gasoline, and meet applicable US fuel standards were evaluated in a naturally aspirated (NA) engine in the legacy fleet, a turbocharged engine in the legacy fleet, and a prototype turbocharged super lean-burn engine, to identify their effects on thermal efficiency and exhaust emissions. As a result, it was confirmed that the lower-carbon intensity fuel can provide almost equivalent engine power and thermal efficiency as conventional fuel, and good
Takada, KeishiSugata, KenjiMatsubara, NaoyoshiTakahashi, DaishiVuilleumier, DavidMorlan, BrianLorenz, RobertOhta, Satoshi
The development of new internal combustion (IC) engine technologies is essential as the automotive industry moves towards hybrid powertrains. Six-stroke (6S) gasoline compression ignition (GCI) engine is one such promising technology. It has the potential to improve performance and reduce emissions by introducing an additional power stroke (PS2) after the first power stroke (PS1). The aim of this study was to determine the optimal injection parameters for 6S GCI operation with one injection event in each power stroke. Parameters included the start of first (SOI1) and second injection (SOI2), and the fuel split ratio (SR) between PS1 and PS2. The study focused on mid (12, 15 bar) to high (18, 21 bar) engine loads, relevant for hybrid powertrains. Genetic algorithm technique was employed to optimize thermal efficiency while adhering to constraints on soot, NOx, maximum pressure rise rate (MPRR), and peak cylinder pressure (PCP). For 12 bar load, delaying the SOI1 timing to -4 CA ATDC led
Ullal, AnkithZhu, ShengrongHa, Kyoung PyoPurushothaman, Ashwin KarthikRa, Youngchul
The transportation sector is responsible for a significant portion of greenhouse gas emissions. Within the sector, truck freight is responsible for a third of the associated emissions. Alternative powertrains are seen as a viable approach to significantly reduce these emissions. Prior to making a large-scale transition, it is important to consider the following questions: will the power grid support a transition to alternative powertrains?; will the transition truly reduce carbon emissions?; and will the transition impose an unnecessary economic burden on companies within the industry? The answer to these questions, however, can vary by geography, maturity/capacity of the energy distribution network or predicted vehicle load. We focus on the latter two questions, investigating the variation in estimated total cost of ownership and carbon emissions across the United States at the zip code level for both heavy-duty battery electric vehicles and heavy-duty fuel cell electric vehicles. As
Goulet, NathanSun, RuixiaoFan, JunchuanSujan, VivekMiller, Brandon
A reemergence of manufacturer interest in range-extended electric vehicles is being driven by increasing diversification of consumer interest in low carbon-intensity technologies in the passenger vehicle and other markets. A major advantage of range-extended electric vehicles is that they curtail consumer vehicle range anxiety while maintaining a lower vehicle cost when compared with battery electric vehicles (BEV). By incorporating a small liquid-fueled internal combustion engine (ICE), the range and “refueling” time of electrified vehicles can be significantly improved while overcoming issues with cost and weight faced by long-range battery packs. Compared to ICEs designed for non-hybrid and mild hybrid vehicles, the ICE in a range-extended electric vehicle has a unique set of requirements focused on compact size, low cost, and efficient operation within a limited engine map. A Range Extender (REx) 0.9L 2-cylinder engine was selected which prioritizes these attributes in a
Peters, NathanMarion, JoshuaPothuraju Subramanyam, SaiHoth, AlexanderBunce, Mike
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 Rotating Liner Engine (RLE) is a design concept where the cylinder liner of a heavy-duty Diesel engine rotates at about 2-4 m/s surface speed to eliminate the piston ring and skirt boundary friction near the top and bottom dead center. Two single cylinder engines are prepared using the Cummins 4BT 3.9 platform, one is RLE, the other is baseline (BSL), i.e. conventional. In 2022, we published the test results of the RLE under load, but we lacked detail test data for the baseline. In this new set of experiments, we compare the RLE performance at idle and under load of up to about 7 bar IMEP (indicated mean effective pressure) to the baseline under similar conditions. It has been proven that the elimination of metallic contact between the compression rings and cylinder wall takes place with a liner speed of 1.5-2.3 m/s surface speed (283-426 rpm for the 102 mm bore) for the 850-1280 rpm crankshaft speed. The RLE FMEP is substantially reduced under load, which is a trend opposite to
Dardalis, DimitriosHall, MatthewRiley, SebastianBasu, AmiyoMatthews, Ron
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
Hydrogen as a fuel for internal combustion engines is the most promising candidate for the achievement of the zero-emissions target fixed by the European institutions for sports car applications. The development of a high-specific-power hydrogen engine is not trivial considering the low volumetric energy density of hydrogen. Furthermore, the necessity to reduce the engine encumbrance in favour of on-board fuel storage makes alternative engine architectures, such as the two-stoke opposed-piston design, particularly attractive. A numerical study is conducted to evaluate the potential of such architecture. First, the overall engine is simulated in a 1D-CFD framework assuming a fully homogeneous hydrogen/air mixture. Then, the intake and exhaust port phasing are optimized, and a 3D CAD model of the cylinder is developed based on the defined parameters. 3D-CFD simulations of the scavenging process are performed and employed to tune the 1D model. Starting from a single point injection
Marini, AlessandroVolza, AntonelloBaudone, AntonioMattarelli, EnricoFontanesi, StefanoDi Sacco, MicheleTonelli, RobertoBreda, Sebastiano
In internal combustion engines, hydrogen is considered as one of the most promising alternatives to replace fossil fuels and reduce CO2 emissions. In such a context, traditional injectors for hydrocarbon fuels are currently being tailored to be used with hydrogen, or a single-hole/multi-hole cap mounted at the injector tip was used to obtain better mixing and air utilization. Nevertheless, the hydrogen injection can be accompanied by the formation of highly under-expanded jets and will significantly influence the downstream mixing process. Therefore, in order to achieve a better understanding on hydrogen-air mixture, this work aims to numerically investigate the influence of the nozzle geometry on the jet behaviors in the near nozzle region. The nozzle diameter ranges from 0.1 mm to 2.0 mm and the nozzle length is from 1mm to 2mm. The injection pressure ranges from 10 bar to 70 bar. As the boundary condition varied, differences in both the internal flow of different nozzle structures
Jiahui, LangLi, YanfeiXu, LubingXiao, MaShuai, Shijin
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
Off-highway vehicles, with their unique requirements of durability, high power, and torque density, are typically powered by diesel ignition internal combustion engines (ICEs). This reliance on ICEs significantly contributes to greenhouse gases (GHGs) emissions. For this reason, there is an urge to develop an energy-efficient powertrain architecture that produces fewer GHGs emissions while meeting the variable torque levels and variable speeds and performing various duty cycles with high efficiency. In order to select the energy-efficient powertrain architecture for the off-highway vehicle, different existing powertrain architectures (i.e., series hybrid, parallel hybrid, series-parallel hybrid, conventional) for off-highway applications have been studied to highlight their pros and cons. This is done considering the different duty cycles and applications along with Life Cycle Analysis (LCA). Off-highway vehicles operate under different road/surface conditions than on-road vehicles
Abououf, HendHanif, AtharDickson, JonChandramouli, NitishAhmed, Qadeer
The rise of electric and hybrid vehicles with separate axle or wheel drives enables precise torque distribution between the front and rear wheels. The smooth control of electric motors allows continuous operation on high-resistance roads, optimizing torque distribution and improving efficiency. In hybrid vehicles, synergistic control of both internal combustion engines and electric motors can minimize energy consumption. Using the internal combustion engine for steady driving and electric power for acceleration enhances dynamic performance. Keeping the internal combustion engine at a constant speed is key to improving energy efficiency and vehicle responsiveness. The proposed method aids in selecting optimal power levels for both engines during the design phase. As acceleration time decreases, the ratio of electric motor power to internal combustion engine power increases. The torque distribution system, relying on sensors for axle loads, vehicle speed, and engine power, can reduce
Podrigalo, MikhailSergyjovych, Oleksandr PolianskyiKaidalov, RuslanDubinin, YevhenAbramov, DmytriiMolodan, AndriiAndrey, KorobkoKholodov, MykhailoOmelchenko, VasylKrasnokutskyi, Maksym
Selective catalytic oxidation/reduction catalysts coated on diesel particulate filters (SDPF) are an important technology route to meet next-stage emission regulations. The previous research of the research group showed that compared with SDPF coated with Cu-SSZ-13, the SDPF coated with novel selective catalytic oxidation-selective catalytic reduction (SCO-SCR) catalyst, which combined MnO2-CeO2/Al2O3 and Cu-SSZ-13, can simultaneously improve NOx reduction and soot oxidation performance. Catalyst coating strategy is an important parameter affecting the performance of SDPF. In this study, the effects of different coating strategies of SCO-SCR catalysts (C25, C50, C75, and C100) on the performance of NOx reduction and soot oxidation in SDPF were investigated. The results show that, as the inlet gas temperature increases, NO emissions first decrease and then increase, NOx conversion efficiency first increases and then decreases, and the rich-NO2 area, NH3 oxidation rate, N2O, CO, CO2
Chen, Ying-jieTan, PiqiangYao, ChaojieLou, DimingHu, ZhiyuanYang, Wenming
As the agricultural industry seeks to enhance sustainability and reduce operational costs, the introduction of mild hybrid technology in tractors presents a promising solution. This paper focuses on downsizing internal combustion (IC) engine, coupled with integration of electric motor, to reduce fuel consumption and meet stringent emission regulations while maintaining power requirement for agricultural applications in India. The hybridization aims to deliver instant power boosts during peak loads and capitalizes on energy recovery during part loads and braking. Furthermore, the idle avoidance feature minimizes fuel consumption during periods of inactivity thus improving fuel efficiency. The hybridization also aims to hybridize auxiliary systems for flexible power management, enabling operation of either engine, auxiliaries, or both as needed. A newly developed hybrid supervisory control prototype efficiently manages electric power and mechanical power, enabling intelligent management
Prasad, Lakshmi P.PS, SatyanarayanaPaygude, TejasGangsar, PurushottamThakre, MangeshChoudhary, NageshGitapathi, Ajinkya
A major portion of the energy consumed in a vehicle is spent on keeping the occupants thermally comfortable in all environmental conditions when the heating, ventilation, and air-conditioning (HVAC) system is turned on. Maintaining the thermal comfort of a passenger is critical in terms of fuel consumption and emission for internal combustion engine (ICE) vehicles. In electrified vehicles, where range is of major concern, this gains further-more importance. SC03 is a test defined by the US Environmental Protection Agency (EPA) to measure tailpipe emissions and fuel economy of passenger cars with the air-conditioner on. The current study would focus on this drive cycle on an ICE vehicle. The co-simulation framework would include a 1D thermal system model, associated thermal controls, a vehicle cabin model, and a human thermal model. 1D model will be predicting the energy consumption via compressor power, refrigerant pressure and temperature across the loop, component heat rejection, etc
Natarajan, ShankarBalasubramanian, Sudharsan
Battery electric vehicles (BEVs) are well-suited for many passenger vehicle applications, but high cost, short range, and long recharging times have limited their growth in commercial vehicle markets. These constraints can be eliminated with plug-in hybrid electric vehicles (PHEVs) which combine many benefits of BEVs with those of conventional vehicles. In this study, research was conducted to determine the optimal hybrid electric powertrain system for a Class 3, light duty commercial vehicle. The key technologies used in this hybrid powertrain include engine downsizing, P3 architecture hybridization, and active thermal management of aftertreatment. A vehicle cost of ownership analysis was conducted to determine the economic viability, a very important consideration for commercial vehicles. Several combinations of E-motor and battery pack sizes were evaluated during the cost analysis and the best possible configuration was determined. The resulting vehicle powertrain demonstrated ~60
Meruva, PrathikMichlberger, AlexanderBachu, PruthviBitsis, Daniel Christopher
The paper documents the modeling and experimental work on a common rail fuel injection system for Dimethyl Ether, a potential diesel substitute with a low carbon intensity signature. The DME fuel system is deployed on a light duty 2.2L compression ignition engine. The paper describes the injector optimization to shift to higher flows to account for the lower heating value and density of the DME when compared to diesel. The type of the injection system used for the DME application is an advanced rendering of the Common rail noted for a one-piece piston-needle injector construction and a solenoid driven spill valve featuring a pressure balanced poppet. A dedicated high-pressure fuel pump designed to pressurize DME is used. The design results in a fast acting open and close injection event, reduced leakage, with reduced cavitation in the fuel injector volume. Design parameters for system optimization included fill and spill orifices, needle lift, bias spring, and injector hole size. The
De Ojeda, WilliamWu, Simon (Haibao)
The challenges with electrification in the automotive industry have led to rethinking the decisions to ban internal combustion engines. Nonetheless, decarbonization of transportation remains a regulatory priority in many countries, irrespective of the energy source for automotive powertrains. Renewable oxygenated fuel components can help with the rapid decarbonization of gasoline fuels in the current fleet. Ethanol is one of the primary renewable components typically used for blending in gasoline primarily at 10% v/v but up to 20% v/v substitution which corresponds to 3.7 to 8.0% oxygen by mass. However, a range of oxygenates could be used instead of ethanol. This study aimed to determine if the engine could discriminate between different oxygenates in gasoline fuels blended at the same octane (RON) and oxygen levels. Oxygenates such as methyl-tert-butyl-ether (MTBE) and ethyl-tert-butyl-ether (ETBE) were considered in this study. Blends were made using a combination of n-heptane, iso
Kalaskar, VickeyMitchell, RobertPourreau, Daniel
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
Alpha Engineered Composites’ thin profile textile composite heat shields provide thermal protection through several thermodynamic mechanisms including: radiation reflection; heat spreading; and finally heat transfer resistance. Typical under the hood automotive applications require heat shield average operational temperature up to 225°C, but newer internal combustion engines are being designed for higher operational temperatures to: increase efficiency through higher compression cycle ratios and lean burning; boost power through turbocharging; increase energy density; and support advanced emissions controls like EGR that can increase average operational temperature up to 300°C. Unfortunately, thermo-oxidative degradation mechanisms negatively impact the polymer structural adhesive within a heat shield textile composite and degrade thermal protection mechanisms. High average operational temperature degradation of traditional versus next generation textile composite heat shields is
Vazquez, Mark
The integration of low-octane gasoline with a compression ignition combustion system has been proposed as a strategy to reduce Well-to-Wheel CO2 emissions from automobiles in petroleum-based fuel. However low-octane gasoline is not widely available in the market currently. Onboard reforming of commercial gasoline to increase the cetane number (lower the octane number) allows for compression ignition combustion even with commercial gasoline. To reform commercial gasoline, a reformer with a spiral structure reactor and mechanical stirring air introduction was designed and prototyped based on the results of toluene reforming tests (A Study on Cetane on Demand Technology Part 1: Development of fuel reformer to improve fuel ignitability). Using N-hydroxyphthalimide (NHPI)-supported ZSM-5 as a catalyst, commercial gasoline was reformed. As a result, 25.5 liters of reformed gasoline was obtained. The hydroperoxide concentration in the entirety of our reformulated gasoline was determined to be
Matsuura, KatsuyaHashimoto, KohtaroYamada, YoshikazuAl-Taher, MaryamKalamaras, ChristosVoice, AlexanderBhadra, Kaustav
Combining a low-carbon content fuel, such as natural gas, with a high-efficiency engine can reduce greenhouse gas emissions significantly in hard-to-electrify long-haul trucking applications. Turbo-compounding, where an additional power turbine is installed in the exhaust stream after the turbocharger turbine, can extract useful amounts of energy from diesel engine exhaust at high loads. This work assesses the net benefits of combining turbo-compounding with a high-efficiency, natural gas fuelled heavy-duty engine. The effects on brake specific fuel consumption (BSFC), greenhouse gas emissions, and engine-out emissions of nitrogen oxides (NOx) and methane (CH4) are considered. The experimentally validated 1D model for a 13L diesel pilot- direct injection of natural gas, heavy-duty engine in GT-SUITETM is used to develop a series turbo-compound model. The effects of turbine sizes and flow capacities in fixed-geometry turbocharging and power turbines are evaluated on the engine’s
Balazadeh, NavidMunshi, SandeepShahbakhti, MahdiMcTaggart-Cowan, Gordon
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
Interest in Battery-Driven Electric Vehicles (EVs) has significantly grown in recent years due to the decline of traditional Internal Combustion Engines (ICEs). However, malfunctions in Lithium-Ion Batteries (LIBs) can lead to catastrophic results such as Thermal Runaway (TR), posing serious safety concerns due to their high energy release and the emission of flammable gases. Understanding this phenomenon is essential for reducing risks and mitigating its effects. In this study, a digital twin of an Accelerated Rate Calorimeter (ARC) under a Heat-Wait-and-Seek (HWS) procedure is developed using a Computational Fluid Dynamics (CFD) framework. The CFD model simulates the heating of the cell during the HWS procedure, pressure build-up within the LIB, gas venting phenomena, and the exothermic processes within the LIB due to the degradation of internal components. The model is validated against experimental results for an NCA 18650 LIB under similar conditions, focusing on LIB temperature
Gil, AntonioMonsalve-Serrano, JavierMarco-Gimeno, JavierGuaraco-Figueira, Carlos
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
A total of 368 frontal New Car Assessment Program (NCAP) tests (including 24 tests with Battery Electric Vehicles (BEVs)) with high-resolution load cell data were analyzed to investigate vehicle crash compatibility, especially between Internal Combustion Engine Vehicles (ICEVs) and BEVs. An Indirect Frontal Crash Model (IFCM) for Full-Overlap (FO) Vehicle-to-Moving Deformable Barrier (V2MDB) using load cell data from frontal NCAP tests was developed to assess vehicle aggressivity. An analytical solution of the IFCM for FO/V2MDB was obtained and used to develop a new aggressivity metric. In addition, the Max. Standard Deviation (SD) of load cell forces was used to assess vehicle front-end homogeneity. In the case studies, vehicle compatibility was assessed by the new aggressivity metric and Max. SD, along with typical frontal crash metrics.
Park, Chung-Kyu
This paper reports on the development of a simulation model to predict engine blowby flow rates for a common rail DI diesel engine. The model is a transient, three-dimensional computational fluid dynamics (CFD) model. Managing blowby flow rates is beneficial for managing fuel economy and oil consumption. In doing so, an improved understanding of the blowby phenomenon is also possible. A mesh for the sub-micron level clearances (up to 0.5 microns) within the piston ring pack is created using a novel approach. Commercial CFD software is used to solve the pressure, velocity, and temperature distributions within the fluid domain. Ring motions within the piston grooves are predicted by a rigorous force balance. This model is the first of its kind for predicting engine blowby using a three-dimensional simulation model while solving the complete set of governing transport equations, without neglecting any terms in the equations. The predicted blowby flow rate has been validated with
Manne, Venkata Harish BabuBedekar, SanjeevSrinivasan, ChiranthDas, DebasisRanganathan, Raj
Diesel aftertreatment (AT) systems are critical for controlling emissions of CO, HC, NOX, and PM in the on-road transportation sector. Ensuring compliance with regulatory standards throughout the AT system's lifespan requires precise prediction of various degradation mechanisms under real-world operating conditions and mitigating their impact through proper catalyst sizing and advanced controls. In the SwRI A2CAT-II consortium, a medium-duty diesel engine production aftertreatment system was subjected to full useful life aging, involving chemical poisoning with phosphorus (P) and sulfur (S) species, along with hydrothermal aging following the DAAAC protocol. This study was aimed to model and predict the aging trajectory of this production AT system thereby capturing changes in system dynamics under both steady-state and transient conditions. The system, designed to meet the 0.2 g/bhp-hr standard, comprised a Diesel Oxidation Catalyst (DOC), Diesel Particulate Filter (DPF), Selective
Balakrishnan, ArunChundru, Venkata RajeshEakle, ScottSharp, Christopher
A diesel engine was run on off-highway cycle sequence on nine (9) fuels and blends. Number-weighted solid particle size distribution (PSD) in the size range from 5.6 nm to 560 nm was measured at inlet and outlet of a diesel particulate filter (DPF) on a sequence of five (5) non-road transient cycles (NRTCs) and five (5) non-road steady-state cycles (NRSCs). The measurements were used to correlate the fuel properties to the DPF-In concentrations and filtration of different size particles in the DPFs. The data showed an expected trend with the DPF-In emissions. Ultra-low sulfur diesel (ULSD) had the highest solid particle number (SPN) concentrations and biodiesels (soy-based biodiesel (B100) and rapeseed-based biodiesel (RME)) had the lowest concentrations. The geometric number mean diameter (GNMD) of DPF-In PSD correlates with the concentrations. The calculated GNMD was the highest for ULSD and lowest for B100/RME. An opposite trend for the GNMD was observed at the DPF-Out where the
Lakkireddy, VenkataKhalek, ImadBuffaloe, Gina
Plug-in Hybrid Electric Vehicles (PHEVs) combine the benefits of electric propulsion and storage with the extended range of conventional internal combustion engines to reduce fuel consumption and greenhouse gas emissions. However, optimizing the efficiency of PHEVs in real-world driving conditions remains a challenge due to the uncertainties of environmental and driving conditions. Connectivity and automation technologies can offer a unique opportunity to enhance the efficiency of PHEVs by enabling real-time interaction with surrounding vehicles and infrastructure. By leveraging these technologies, significant reductions in energy consumption for PHEVs can be achieved. However, most existing works primarily rely on simulation-based analyses to evaluate energy savings offered by connected and automated PHEVs. This study advances the understanding of the energy-saving potential of connected and automated PHEVs by incorporating experimental validation alongside simulation-based analyses
Kibalama, DennisOzkan, Mehmet FatihStockar, StephanieCanova, MarcelloRizzoni, Giorgio
Minimizing the time needed to achieve light-off temperatures in diesel engine aftertreatment devices is key to mitigate pollutant emissions during the first minutes of operation. Catalyst heating operation typically includes one or multiple post-injections late during the expansion stroke aimed to increase the enthalpy of the exhaust gases. However, post-injection retardability is constrained by low combustion efficiency and the formation of CO and unburned hydrocarbons that cannot be oxidized by a still-inactive oxidation catalyst. In this study, the effects of post-injection strategy on the performance and emissions of a medium duty diesel engine have been investigated experimentally, focusing on the impacts on post-injection retardability. A five injection strategy (two pilot, one main, two post) was implemented in the engine, and the injection duration ratio between the two post-injections has been varied systematically while performing post-injection timing sweeps to identify the
Lopez Pintor, DarioLee, SangukCho, SeokwonBusch, StephenWu, AngelaNarayanan, AbhinandhanAbboud, Rami
On-board diagnosis (OBD) of gasoline vehicle emissions is detected by measuring the fluctuations of the rear oxygen sensor due to the time-dependent deterioration of the oxygen storage capacity (OSC) contained in the automotive catalyst materials. To detect OBD in various driving modes of automobiles with an order of magnitude higher accuracy than before, it is essential to understand the OSC mechanism based on fundamental science. In this study, time-resolved dispersive X-ray absorption fine structure (DXAFS) using synchrotron radiation was used to carry out a detailed analysis not only of the OSC of ceria-based complex oxides, which had previously been roughly understood, but also of how differences in design parameters such as the type of precious metals, reducing gases (CO and H2), detection temperatures, and mileages (degree of deteriorations) affect the OSC rate in a fluctuating redox atmosphere. A fundamental characteristic was clearly demonstrated in ceria-based complex oxides
Tanaka, HirohisaMatsumura, DaijuUegaki, ShinyaHamada, ShotaAotani, TakuroKamezawa, SaekaNakamoto, MasamiAsai, ShingoMizuno, TomohisaTakamura, RikuGoto, Takashi
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