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This paper seeks to optimise fleet management for companies that utilise both internal combustion engine vehicles (ICEVs) and electric vehicles by considering various costs, including fixed costs, variable costs, time window penalty costs, fuel costs, and electricity consumption costs. Additionally, the study examines the influence of four types of regulations, i.e. carbon cap, carbon tax, carbon trading, and carbon offsetting, on carbon emissions and fleet configuration. The optimisation model was solved using a Clarke-Wright savings heuristic algorithm followed by an improved adaptive genetic algorithm (IAGA), and a sensitivity analysis was conducted under different regulatory policies. The results show that all four types of regulations can effectively reduce fleet emissions. While carbon prices have a greater impact on carbon regulations than carbon quota, carbon trading was more effective under similar circumstances. Therefore, governments should implement appropriate regulatory strategies to reduce energy consumption and encourage enterprises to reduce their emissions. [ABSTRACT FROM AUTHOR]

The tetrahedral amorphous carbon (ta-C) coatings are deposited on piston rings to improve the tribological property of the piston ring-cylinder liner system of the internal combustion engines. The deposition parameters are optimized by molecular dynamics simulation to reduce the cost of coatings' fabrication. The ta-C coatings with higher sp3 fraction, lower friction coefficient, and superior anti-wear properties are achieved by optimizing the incident energy and substrate temperature of carbon atoms. The second nearest-neighbor modified embedded-atom method potential and Tersoff potential are used to describe the interatomic interactions. The effects of the incident energy of the carbon atoms and substrate temperature on the deposition properties of the ta-C coatings are discussed. The numerical results show that the ta-C coatings with high sp3 fraction, high density, and good interface mixing are obtained, and the deposition properties of the ta-C coatings are improved. [ABSTRACT FROM AUTHOR]

In this study, a novel system is proposed that includes photovoltaic thermal (PVT), alkaline fuel cell (AFC) and combined cooling, heating, and power system based on internal combustion engine (CCHP). Two operational strategies (PGD: priority given to domestic hot water; PGL: priority given to cooling/heating) have been proposed based on the sequence of waste heat from internal combustion engine. An optimization model is built in TRNSYS with the goal of minimizing life cycle cost and key equipment capacity and operating parameters are chosen as optimal variables. The optimized system is evaluated in five climate zones based on net present value (NPV), carbon dioxide emission and energy utilization rate. The results indicate that: (1) the NPV of Harbin and Changsha PGD strategy increases by 3.6% and 8.97%, respectively, compared with the NPV of PGL strategy. The NPV of the PGL strategy in Beijing, Kunming, and Guangzhou increased by 6.12%, 4.11%, and 1.25%, respectively, compared with the NPV of the PGD strategy; (2) the CO 2 emission is lower for the PGD strategy, with reduction of 7.55%, 15.14%, 8.41%, 14.07%, and 13.65%, respectively, compared with the PGL strategy; (3) the energy efficiency in five climate zones is higher for the PGD strategy, compared with the PGL strategy, which is 7.5%, 11.11%, 6.02%, 13.5%, and 6.59%, respectively. • The PVT - AFC - CCHP system is simulated and optimized in TRNSYS software. • The effect of two operational strategies on system optimization has been researched. • The impact of climate conditions on system optimization has been taken into account. • The optimal results are analyzed from view of economy, environment and efficiency. [ABSTRACT FROM AUTHOR]

In response to the carbon neutrality in internal combustion engines, this study investigates the effects of hydrogen addition on flame propagation dynamics for gasoline flames using a constant-volume chamber at an initial temperature of 400 K. The experiments span a wide range of equivalence ratios (0.7–1.6), pressures (0.1–0.2 MPa), and hydrogen mixing ratios (0%–100%). Results indicate that the normalized laminar burning velocity can exceed 20 at ϕ = 1.6. The influence of hydrogen addition on laminar burning velocity is primarily attributed to chemical effects, followed by dilution effects, and then thermal effects. Additionally, hydrogen addition increases flame instability under fuel-lean conditions but decreases it under fuel-rich conditions. As the equivalence ratio increases, the flame instability intensifies at low hydrogen mixing ratios whereas it diminishes for hydrogen mixing ratios larger than 75%. The measured acceleration exponents are 1.1–1.4, which are below the critical value of 1.5 for self-turbulization. • LBVs of gasoline/H 2 /air are measured with key reactions being revealed. • H 2 affects LBVs through chemical, dilution, and thermal effects in order. • H 2 increases flame instability in lean mixtures but reduces it in rich ones. • Diffusional-thermal and hydrodynamic instabilities have not led to self-turbulization. [ABSTRACT FROM AUTHOR]

As the need for changes in transportation grows, the transition to sustainable mobility is being envisioned in varying ways. Shifting from traditional internal combustion engine vehicles (ICEVs) to electric vehicles (EVs), along with changing mobility habits, will both be necessary. What has been neglected from the study is the role of sport in aiding this transition. Motorsport has long served dual roles of serving as a technological testbed and center for culture formation around street cars. Coupling one of the largest sporting platforms in the world with the missions of climate change awareness and technological advancement, two racing leagues are catalyzing the move to electric mobility. Formula E and Extreme E have released documentary films showcasing their future goals. To understand the role of electric racing in shaping the transition to sustainable mobility, this paper uses a grounded theory approach to identify relevant themes of the EV transition, while a narrative analysis is used to foreground the overall storytelling aspect of the ecocinematic films. The racing EV emerges as a site of collective collaboration: meeting the needs of the future within the framing of traditional motorsport, and merging traditionally masculinist narratives of automotive technology with prototypically feminized environmentalism. [ABSTRACT FROM AUTHOR]

In order to meet the increasingly stringent emission regulations for NOx in the exhaust gas of engines, selective catalytic reduction (SCR) technology is extensively studied and practiced. The key to this technology is the catalyst utilized in the chemical reactions of SCR. It is required to develop the SCR catalyst with good low-temperature performance and a wide active temperature window. A series of Cerium-based metal oxides TiCemWrO2−δ synthesized by solution combustion synthesis is studied in this paper. The SCR activity test was used to select the catalyst with the best performance. The NO conversion rate of the best catalyst in our studies reached 80% at 150 °C, kept 100% from 200 °C to 420 °C and the N2 selectivity remained above 95% for 100–500 °C. The SO2 resistance test was carried out at 250 °C and proved that our catalyst had good SO2 resistance. During the test, the NO conversion rate slightly decreased while 100 ppm SO2 was injected, but it remained above 80% for 24 h. The NO conversion rate recovered to the original value when the SO2 supply was cut off. The N2 selectivity remained at 100% throughout the process. Catalysts were characterized using BET, XRD, and SEM methods. In-situ DRIFTS method was used to study the reaction mechanism of the TiCe0.2W0.2O2−δ catalyst. It showed that the NH4+ species absorbed on the Brønsted acid played a dominant role in the SCR reactions. The bridge nitrate resulted from the NO absorption and gas phase NO was involved in the reaction. In conclusion, the mechanism studied included two routes of L-H and E-R. [ABSTRACT FROM AUTHOR]

In response to the urgent need for sustainable fuels to meet stringent emissions regulations and the dual carbon targets, ammonia has emerged as a promising zero-carbon alternative for internal combustion engines. Despite its potential, the low combustion velocity and high self-ignition temperature of ammonia present significant challenges. This study investigates the use of ammonia blended with dimethyl ether (DME) in Homogeneous Charge Compression Ignition (HCCI) engines, a combustion mode that offers low NOx emissions. A detailed reaction mechanism for ammonia/DME was optimized using progressive reduction techniques, including the Direct Relation Graph Method based on Error Propagation (DRGEP), Direct Relation Graph Method based on Path Flux Analysis (DRGPFA), and Full Species Sensitivity Analysis (FSSA). Six key elementary reactions (R26, R76, R135, R268, R280, R282) were determined through sensitivity analysis, and the chemical reaction rate constants were fine-tuned using response surface methodology to improve the prediction accuracy of Ignition Delay Time (IDT), Laminar Flame Speed (LFS), and engine performance. Ultimately, three sets of optimized mechanisms (opt1, 2, 3) were obtained. Due to the lack of experimental data on HCCI engines, the optimized mechanism was indirectly validated by simulating IDT, LFS, and species concentration under HCCI conditions using CHEMKIN, thereby improving the prediction of combustion dynamics and emission characteristics of HCCI engines. The findings indicate that the optimized mechanism closely approximates the detailed mechanism's predictions, especially opt1, while significantly reducing computational complexity. [Display omitted] • Validated Ammonia-DME HCCI mechanisms for IDT, LFS, and species concentrations. • Developed a reduced mechanism with 46 species and 371 reactions using three methods. • Optimized 3 mechanisms using RSM with minimal deviation from detailed predictions. • Opt1 accurately predicted pressure, IMEP, BSFC, and NOx for 40% DME/60% ammonia. [ABSTRACT FROM AUTHOR]

In the context of global efforts to achieve carbon neutrality, the internal combustion engine industry is progressively shifting toward cleaner fuels. This study examines the impact of direct hydrogen injection position on the combustion process of an X-rotor engine equipped with an offset combustion chamber, aiming to enhance rotor performance and mitigate pollutant emissions. Utilizing CONVERGE software, a three-dimensional dynamic computational fluid dynamics (CFD) model was constructed. The findings indicate that hydrogen injected directly into the cylinder interacts with the mainstream flow during the mixture formation process. Hydrogen entrainment occurs due to the influence of the mainstream flow, leading to the formation of vortices in the injection region. Generally, hydrogen injected from position III is more likely to blend with the gasoline-air mixture in the cylinder, resulting in a homogeneous combustible mixture that promotes effective flame propagation. Specifically, the highest in-cylinder pressure (14.1% and 19.2% greater than injection positions I and II, respectively) is achieved at this injection position. Additionally, the combustion propagation speed is the fastest, and cumulative heat release reaches its peak at 18.07 J, with an indicative thermal efficiency of 25.8%. While these conditions reflect optimal combustion performance, they also correspond to the highest levels of nitrogen oxides (NO x) and carbon monoxide (CO) emissions. • Designed a hydrogen direct injection X-type rotary engine with biased combustion chamber. • A three-dimensional model of X-type rotary engine was developed. • The hydrogen from injection position III is favorable for mixture formation and combustion. • The highest pressure in the cylinder was obtained at the injection position III. [ABSTRACT FROM AUTHOR]

Rising concern for global energy demand has increased researches for a substitute fuel for Internal Combustion Engine (ICE). The underlying objective of this study is to find out the performance, emission and vibration characteristics of diesel engine by making use of Oxy-Hydrogen (HHO) gas. Electrolysis of water provides HHO gas, a better alternative fuel for IC engine. This paper presents key attributes of the use of HHO gas in IC engine with additive Di Tert Butyl Peroxide (DTBP). In this regards, experiments were conducted on single cylinder four strokes, direct injection diesel engine, power 3.5 kW at constant speed of 1500 RPM, Kiloskar model TV1 with pilot fuel as diesel and HHO gas as secondary fuel with additive DTBP. Increase in BTE 6.2 % was observed with use of 5% additive DTP in diesel fuel, however, in dual fuel mode 3.8 % increase in brake thermal efficiency (BTE) was observed with 5 L per minute (LPM) HHO gas and 5 % DTBP. Exhausts emissions (gm/kWh) like un-burnt hydrocarbon (HC), carbon monoxide (CO), carbon dioxide (CO 2) and vibration (Hz) decreases 46.15%, 42.36%, 67.50% and 8.78% respectively by use of 7 LPM flow rate of HHO gas and along with 5% additive DTBP at higher load (68%) conditions while NO x decreases 14.90% by use of 7 LPM flow rate of HHO gas at 34% load condition. • BTE (%) is enhanced 24.2 % to 28% with 5% DTBP and 5 LPM of HHO gas. • Carbon monoxide decreases 67.50% by use of 7 LPM HHO and 5% DTBP at 68% load. • Carbon di-oxide decreases 42.36% by use of 7 LPM HHO and 5% DTBP at 68% load. • Hydrocarbon decreases 46.15% by use of 7 LPM HHO and 5% DTBP at 68% load. • NO x decreases 14.90% by use of 7 LPM HHO at 34% load condition. [ABSTRACT FROM AUTHOR]

Lean burn is increasingly recognized as a prospective operational mode for diverse combustion systems, with the potential to reduce combustion temperatures and thereby lower NOx emissions. However, challenges arise due to the lower flammability limit and reduced flame speeds associated with lean conditions. Hydrogen, with its wide flammability range, stands out as a particularly clean candidate for future internal combustion engines (ICEs) operating at ultra-lean and lean conditions. Despite extensive hydrogen ignition delay time (IDT) measurements in the literature, there remains a notable gap at low equivalence ratios for fuel–air mixtures. Existing experiments often involve high levels of dilution. Our work addresses this gap by measuring IDTs of H 2 -air mixtures at ϕ = 0.2 – 0.6 and across a range of temperatures T = 970 – 1250 K in a rapid compression machine (P = 15 bar) and a high-pressure shock tube (P = 15 and 30 bar). Using a novel optical chamber for the twin-piston RCM and an end wall imaging setup with large depth of field in the shock tube, the preignition behavior and incident shock ignition of hydrogen mixtures were observed in the rapid compression machine and high-pressure shock tube, respectively. IDT measurements were also performed using hydrogen mixture in a diaphragmless mode of shock tube operation and the results were found to be in good agreement with those measured in the conventional (diaphragm) mode. The present work extends the range of measurements, introduces innovative visualization methods for high-pressure combustion processes and demonstrates the use of diaphragmless shock tubes for high-reactivity fuels like hydrogen. • Ignition delay times presented for H 2 -air mixtures at ϕ = 0.2–0.6 and T = 970–1250 K. • High-speed imaging with pressure data offers valuable new insights. • AramcoMech 2.0 predicts well at higher temperatures. • GRIMech and Burke et al.'s models perform well at lower temperatures. • Diaphragmless shock tube works well for sensitive fuels like hydrogen. [ABSTRACT FROM AUTHOR]

Methanol is widely recognized as a promising alternative fuel for achieving carbon neutrality in internal combustion engines. Its use in direct injection spark-ignition (DISI) engines, either as pure methanol or blended fuels, has demonstrated improvements in thermal efficiency and reductions in certain gaseous pollutants. However, due to the complex influencing factors and the great harm to human health, its particulate emissions need to be further explored and controlled, which is also an inevitable requirement for the development of energy conservation and carbon reduction in internal combustion engines. This study explores the effects of two-stage injection strategies combined with fuel blending on the combustion characteristics, stability, and particulate emissions of DISI engines. By testing four methanol blending ratios and four injection ratios, the presented study identifies that M20 fuel with an 8:2 injection ratio achieves optimal combustion performance, stability, and increased indicated mean effective pressure. Furthermore, under low methanol blending ratios, the 8:2 injection ratio can reduce particulate number concentrations by approximately 20%. These findings suggest that a well-designed two-stage injection strategy combined with methanol–gasoline blends can effectively control particulate emissions while maintaining the power, efficiency, and combustion stability of DISI engines. [ABSTRACT FROM AUTHOR]

The automotive industry is under increasing pressure to develop cleaner and more efficient technologies in response to stringent emission regulations. Hydrogen-powered internal combustion engines represent a promising alternative, offering the potential to reduce carbon-based emissions while improving efficiency. However, the accurate estimation of in-cylinder pressure is crucial for optimizing the performance and emissions of these engines. While traditional simulation tools such as GT-POWER are widely utilized for these purposes, recent advancements in artificial intelligence provide new opportunities for achieving faster and more accurate predictions. This study presents a comparative evaluation of the predictive capabilities of GT-POWER and an artificial neural network model in estimating in-cylinder pressure, with a particular focus on improvements in computational efficiency. Additionally, the artificial neural network is employed to predict the equivalent flame radius, thereby obviating the need for repeated tests using dedicated high-speed cameras in optical access research engines, due to the resource-intensive nature of data acquisition and post-processing. Experiments were conducted on a single-cylinder research engine operating at low-speed and low-load conditions, across three distinct relative air–fuel ratio values with a range of ignition timing settings applied for each air excess coefficient. The findings demonstrate that the artificial neural network model surpasses GT-POWER in predicting in-cylinder pressure with higher accuracy, achieving an RMSE consistently below 0.44% across various conditions. In comparison, GT-POWER exhibits an RMSE ranging from 0.92% to 1.57%. Additionally, the neural network effectively estimates the equivalent flame radius, maintaining an RMSE of less than 3%, ranging from 2.21% to 2.90%. This underscores the potential of artificial neural network-based approaches to not only significantly reduce computational time but also enhance predictive precision. Furthermore, this methodology could subsequently be applied to conventional road engines exhibiting characteristics and performance similar to those of a specific optical engine used as the basis for the machine learning analysis, offering a practical advantage in real-time diagnostics. [ABSTRACT FROM AUTHOR]

Hydrogen (H 2) is a carbon-free chemical energy carrier and one promising solution for achieving effective decarbonization of the transportation sector, particularly for internal combustion engines (ICEs). With a focus on ICEs, and compared to port-fuel injection, direct injection (DI) of gaseous H 2 during the compression stroke offers potential advantages, which include backfire avoidance and reduction of preignition occurrence. In these last two decades, much research, experimental and numerical, has been devoted to understanding H 2 's mixing and combustion processes in ICEs. Computational fluid dynamics modeling efforts commonly rely on unsteady Reynolds-averaged Navier Stokes (URANS) turbulence frameworks, mostly due to their computational affordability. However, many authors have pointed out the opportunity to perform large-eddy simulations (LESs) to investigate the cyclic variability of H 2 engines and assess potential advantages of using LES in place of URANS, especially for lean operation. This study addresses this knowledge gap and presents a computational fluid dynamics (CFD) study of the H 2 DI process in an optical engine operating at relatively low tumble conditions, using multicycle LESs. The manuscript presents a thorough validation of the results against experimental data available from the literature as well as direct comparison with URANS, demonstrating the feasibility of multicycle LESs for CFD modeling of DI H 2 -fueled ICEs. • Performed multicycle LES of a direct-injection hydrogen-fueled optical engine. • Validated LES against PIV and PLIF data and compared against URANS. • Ideated parallelization strategy to accelerate execution time of LES campaign. • LES can resolve main flow structures under flow-only conditions better than URANS. • LES predicted improved H 2 mixing with ambient gas compared to URANS. [ABSTRACT FROM AUTHOR]

To enhance engine performance, reduce carbon emissions, and minimize fossil diesel fuel usage in internal combustion engine applications, this study explores the influence of hydrogen (H 2) enrichment of 4 LPM on the performance, emission, and combustion characteristics of the diesel engine using n-pentanol with diesel blends. The findings demonstrate that adding H 2 significantly enhances engine performance by increasing thermal efficiency (4%) and reducing fuel consumption (10%). However, higher H 2 content typically leads to a rise in nitrogen oxide (NOx) emissions. This experimental investigation examines the effects of double injection mode, varying pilot and main injection fuel mass at different injection timings (35–55° CA bTDC), on key engine parameters such as thermal efficiency, combustion behavior, and pollutant emissions under different loads. The results indicate that advanced injection timings improve thermal efficiency along with reduced fuel consumption by advancing combustion phasing compared to delayed injection timings. Advancing the pilot fuel injection timing also reduces CO, HC, and NOx emissions, although it emits more soot emissions. This study demonstrates the potential of using double injection mode to enhance the performance, emission, and combustion characteristics of hydrogen-enriched n-pentanol/diesel blends as fuel for engines. It is evident that the negative effects on engines combustion, performance, and emissions caused by n-pentanol can be mitigated by utilizing H 2 in internal combustion engines (ICEs) due to its rise in flame speed as well as heating value. Overall, the n-pentanol/diesel blend with H 2 addition improves engine combustion, resulting in lower fuel consumption and higher thermal efficiency, while reducing emissions of NOx, soot, HC, and CO compared to using diesel fuel alone. • Hydrogen enrichment of n-pentanol/diesel under double injection was investigated. • The thermal efficiency and fuel consumption improved by 4% and 10% respectively. • This lowers the NOx and soot emissions by more than 35 and 90% respectively. • CO and HC emissions significantly decreased mainly at advanced injection timings. • n-pentanol/diesel blend with hydrogen has better engine performance and emissions. [ABSTRACT FROM AUTHOR]

Hydrogen carriers are attractive alternative fuels for the shipping sector. They are zero-emission, have high energy densities, and are safe, available, and easy to handle. Sodium borohydride, potassium borohydride, dibenzyltoluene, n-ethylcarbazole, and ammoniaborane are hydrogen carriers with high theoretical energy densities. The energy density is paramount to implementing hydrogen carriers as a high energy density enables compact and lightweight storage. The effective energy density depends on integrating heat and masses with energy converters. This combination defines the energy efficiency and, thus, the energy density of the system. This paper addresses the effective energy density of the hydrogen carriers, including the dehydrogenation process. Using a 0D model, we combined the five carriers with two types of fuel cells, namely proton exchange membrane (PEM) and solid oxide fuel cells (SOFC), an internal combustion engine and a gas turbine. N-ethylcarbazole and dibenzyltoluene offer medium energy densities, reaching almost 4 MJ/kg. However, the effective energy density of sodium borohydride and ammoniaborane is very high, up to 15 MJ/kg, including the energy converter. This is similar to the energy density of marine diesel oil combined with an internal combustion engine. Thus, we conclude hydrogen carriers are alternative fuels that deserve more attention because of their strong potential to make shipping zero-emission. [ABSTRACT FROM AUTHOR]

Ammonia is a promising option for hydrogen storage, offering high density, low-pressure storage, and stability. Ammonia engines are increasingly adopted in vessels like ferries and cargo ships, showing promise for emissions reduction and economic benefits. However, its toxic, flammable, and corrosive nature poses safety challenges compared to other fuels. The study is identified risks associated with the release, dispersion, and hazardous zones of ammonia. A standardised procedure for assessing the risk of ammonia release in the engine room is established. The case study involves the unintentional release of ammonia in the engine room of a 299 GT general cargo ship. The FLACS-CFD 22.2 is employed to model the leakage of ammonia in the engine room under various leakage scenarios. The study examines the influence of leak rates (0.05 , 1 kg/s, 10 kgs and 50 kg/s), leak directions (longitual, transverse and vertical leaks), and hole size (0.05, 0.5, 5 mm) on the dispersion behaviour of ammonia. The findings indicate that vapour cloud dispersion of ammonia tends to accumulate in the direction of the leakage, particularly at the corner formed by equipment, and surrounds the outlet ventilation. Two crucial factors affecting the dispersion and safety considerations in the engine room are the toxicity and flammable limits of ammonia. It is recommended to implement effective ventilation to reduce the harmful effects of ammonia release. This study contributes to the ongoing efforts in adopting ammonia as a viable alternative fuel in the maritime sector, contributing to reduced airborne exhaust emissions and environmental impact.Abbreviations: AER: Air exchange rate; ACH: Air changes per hour; BLEVE: Boiling liquid expanding vapour explosion; CFD: Computational Fluid Dynamics; DWT: Deadweight tonnage; EEOI: Energy Efficiency Operational Indicator; ESD: Emergency Shutdown; EEDI: Energy Efficiency Design Index; FGSS: Fuel gas supply system; GHG: Greenhouse gas emission; GT: Gross tonnage; HCN: Hydrogen cyanide gases; HP: Horse power; IMO: International Maritime Organization; ICE: Internal combustion engine; ISO: International Organization for Standardization; IGF Code: The International Code of Safety for Ships Using Gases or Other Low-Flashpoint Fuels; LNG: Liquefied Natural Gas; LPG: Liquefied Petroleum Gas; MARPOL: The International Convention for the Prevention of Pollution from Ships; PPE: Personal protective equipment; PFP: Power to fuel to power; PRA: Probabilistic Risk Assessment; PPM: Parts per million; SEEMP: Ship Energy Efficiency Management Plan; SGMF: Society for Gas as a Marine Fuel; QRA: Quantitative risk assessment. [ABSTRACT FROM AUTHOR]

Hydrogen, as a zero-carbon fuel, is becoming an important component for decarbonizing the economy. It can be used not only as a storage medium, but also as a fuel for power generation equipment. Hydrogen is very different in its energy properties (high calorific value, high combustion rate), which are very different from traditional gas turbine fuels, so when burning hydrogen, new unexplored problems may arise during the operation of main and auxiliary equipment. To introduce hydrogen technologies into the traditional energy system, new approaches to equipment operation are required. Gas turbines, unlike other power equipment, can be configured to burn any gaseous fuel that meets the requirements for the combustion chamber. Combustion of 100% H 2 in the combustion chamber of an operating gas turbine is impossible without deep modernization; this can cause damage to the main and auxiliary equipment. Gas turbines powered by hydrogen will be an important component in the decarbonization of all industries. The article discusses the variable operating modes of a gas turbine unit with a capacity of 18 MW, depending on the percentage of H 2 in natural gas. The traditional fuel for gas turbines is natural gas; the presented study considers adding up to 20% hydrogen to the original natural gas. The addition of hydrogen fuel affects the operating mode of the turbine. The operation of a gas turbine unit at various outside temperatures, operation at full and partial load in the conditions of the wholesale electricity market is considered. [Display omitted] [ABSTRACT FROM AUTHOR]

This study investigates the operational properties of mineral lubricating oil in gas engines used in cogeneration systems, with a focus on factors contributing to the degradation of lubricating properties critical for energy efficiency and system management. The research was conducted on a 4.3 MW gas engine operating for about 90,000 machine hours, using natural gas as fuel. Data obtained from SCADA (Supervisory Control and Data Acquisition) systems and laboratory analysis were utilized to establish oil quality criteria, enabling the prediction of oil degradation and optimization of oil change intervals. Parameters including viscosity, contamination levels, Total Base Number (TBN), and Total Acid Number (TAN), were identified as significant indicators of oil performance and engine reliability. The findings revealed that oil change intervals could be extended by an average of 37% compared to standard schedules, thereby minimizing unnecessary maintenance downtimes, enhancing system availability, and increasing electrical and thermal energy output. Optimized oil utilization reduced material costs for oil and filter replacements, lowering expenditures from 3021 to 1887 EUR per machine hour. Additionally, the predicted Global Warming Potential (GWP) for prematurely consumed oil amounted to 68 × 103 kg CO2 eq., while avoidable waste generation reached 18.2 m3 of mineral oil. Regular oil analysis conducted every 1000 operating hours proved critical for early detection of oil degradation, supporting proactive maintenance strategies and ensuring optimal engine performance and longevity. [ABSTRACT FROM AUTHOR]

To ascertain energy availability and system performance, a comprehensive understanding of the systems' degradation profile and impact on overall plant reliability is imperative. The current study presents an integrated Failure Mode and Effects Analysis (FMEA)–Markovian algorithm for reliability-based instantaneous energy performance prediction for thermal energy systems. The FMEA methodology is utilized to identify and categorize the various failure modes of the gas turbines, establishing a reliability pattern that informs overall system performance. Meanwhile, the Markovian algorithm discretizes the system into states based on its operational energy performance envelope. The algorithm predicts instantaneous energy performance according to upper and lower bounds criteria. This integrated methodology has been subjected to testing in three case studies, yielding results that demonstrate improved reliability and instantaneous energy performance prediction during system degradation. It was observed that after 14 years of operation, the likelihood of major failures increases to 79.6%, 88.7%, and 82.8%, with corresponding decreases in system performance reliability of 10.1%, 4.5%, and 7.8% for the Afam, Ibom, and Sapele gas turbine plants, respectively. Furthermore, the percentage of instantaneous mean power performance relative to the rated capacity is 37.9%, 35.1%, and 46.3% for the three gas turbine plants. These results indicate that the Sapele thermal power plant performs better relative to its rated capacity. Overall, this integrated methodology serves as a valuable tool for monitoring gas turbine engine health and predicting energy performance under varying operating conditions. [ABSTRACT FROM AUTHOR]

Methanol can be synthesized using green electricity and carbon dioxide, making it a green, carbon-neutral fuel with significant potential for widespread application in engines. However, due to its low ignition energy and high laminar flame speed, methanol is susceptible to hotspot-induced pre-ignition and even knocking under high-temperature, high-load engine conditions, posing challenges to engine performance and reliability. This paper systematically reviews the manifestations and mechanisms of pre-ignition and knocking in methanol engines. Pre-ignition can be sustained or sporadic. Sustained pre-ignition is caused by overheating of structural components, while sporadic pre-ignition is often linked to oil droplets entering the combustion chamber from the piston crevice. Residual exhaust gas trapped within the spark plug can also initiate pre-ignition. Knocking, characterized by pressure oscillations, arises from the auto-ignition of hotspots in the end-gas or, potentially, from deflagration-to-detonation transition, although the latter requires further experimental validation. Factors influencing pre-ignition and knocking, including engine oil, in-cylinder deposits, structural hotspots, and the reactivity of the air–fuel mixture, are also analyzed. Based on these factors, the paper concludes that the primary approach to suppressing pre-ignition and knocking in methanol engines is controlling the formation of pre-ignition sources and reducing the reactivity of the air–fuel mixture. Furthermore, it addresses existing issues and limitations in current research, such as combustion testing techniques, numerical simulation accuracy, and the mechanisms of methanol–oil interaction, and offers related recommendations. [ABSTRACT FROM AUTHOR]

This paper examines the feasibility of converting a Heavy-Duty (HD) Spark Ignition (SI) Compressed Natural Gas (CNG) engine to biogas fuel. A One-Dimensional (1D) simulation tool was used to model a commercially available HD SI CNG engine. The model was validated by comparing experimental and computed in-cylinder pressure, brake power, fuel, and air mass flow rates. The engine was then modified to use biogas with an injection system based on existing designs from the literature. A Spark Advance (SA) sweep was performed to assess the engine's performance at full load. The chosen equivalence ratio was 0.85, and the engine speed was 1500 rpm. The Maximum Brake Power (MBP) and Maximum Brake Efficiency (MBE) operating points were identified. Partial load analysis was conducted starting from the MBP conditions. Results in terms of brake power, brake efficiency, and NOx emissions are presented. Conversion to biofuel results in a reduction in power and efficiency of 33% and 4%, respectively, at 1500 rpm and full load conditions. Brake Specific NOx emissions remained comparable. This numerical study demonstrates the feasibility of biogas conversion for HD SI engines, offering a renewable fuel alternative to reduce greenhouse gas emissions, though with trade-offs in power and efficiency. [ABSTRACT FROM AUTHOR]

The quest for renewable energy sources has resulted in alternative fuels like ammonia, which offer promising carbon-free fuel for combustion engines. Ammonia has been demonstrated to be a potential fuel for decarbonizing power generator, marine, and heavy-duty transport sectors. Ammonia's infrastructure for transportation has been established due to its widespread primary use in the agriculture sector. Ammonia has the potential to serve as a zero-carbon alternative fuel for internal combustion engines and gas turbines, given successful carbon-free synthesis and necessary modifications to legacy heat engines. While its storage characteristics surpass those of hydrogen, the intrinsic properties of ammonia pose challenges in ignition, flame propagation, and the emissions of nitrogen oxides (NOx) and nitrous oxide (N2O) during combustion in heat engines. Recent noteworthy efforts in academia and industry have been dedicated to developing innovative combustion strategies and enabling technologies for heat engines, aiming to enhance efficiency, fuel economy, and emissions. This paper provides an overview of the latest advancements in the combustion of neat or high-percentage ammonia, offering perspectives on the most promising technical solutions for gas turbines, spark ignition, and compression ignition engines. [ABSTRACT FROM AUTHOR]

Rising greenhouse gas emissions stemming from road transport have intensified the need for efficient and environmentally friendly propulsion technologies. Hybrid and fuel cell electric vehicles have emerged as a viable solution, integrating internal combustion engines and fuel cells with electric motors to optimize fuel efficiency and reduce emissions. This article reviews and analyzes energy management strategies for the principal powertrain topologies of hybrid electric vehicles, focusing on achieving solution optimality in real-time applications. A thorough and comprehensive overview of rule-based, optimization-based, and learning-based energy management strategies is presented, highlighting their main attributes and providing a comparative analysis in terms of fuel economy improvements, real-time implementation feasibility, and computational complexity, while simultaneously identifying and uncovering areas requiring further research in the field. We found that while rule-based methods offer simplicity and real-time capability, their adaptability remains limited. Optimization-based and learning-based approaches, although often achieving near-optimal solutions, face challenges due to their high computational demands and integration complexities. Our analysis also revealed the importance of leveraging vehicle connectivity and intelligent transportation systems for future energy management developments, which will contribute to broader sustainability goals in the automotive sector. [ABSTRACT FROM AUTHOR]

In the present study, office waste paper was employed as feedstock for bioethanol production. Lignocellulosic material was pre-treated with dilute sulphuric acid (5 %) to release monomeric sugars. Acid pretreatment of waste papers was carried out at different ratios of 10, 15, and 20 ml for each 1 gm of raw material to obtain the best yield of hydrolysate. After the pH adjustment of each paper hydrolysate, the hydrolysate was subjected to fermentation and distillation processes respectively. The fermentation process was performed using Saccharomyces Cerevisiae to convert the released sugars to bio-ethanol as a main product. The highest bio-ethanol yield (28.3%) was obtained at a high concentration from the yeast fermentation using waste paper pretreated with acid at a ratio of 10:1 ml/gm (liquid to solid). Economically, office waste paper is a suitable raw material for sustainable bio-ethanol production. Furthermore, bioethanol obtained was blended with pure gasoline at increasingly higher concentrations. A gasohol was homogenously mixed with four formulated fuels such as gasoline blend (E0), gasoline–5% bio-ethanol blend (E5), gasoline–10% bio-ethanol blend (E10), and gasoline–15% bio-ethanol blend (E15). It is critical to investigate the effect of various bio-ethanol blends on the characteristics and performance of internal combustion fuel. These binary mixtures were tested using density, Ried vapor pressure (RVP), and Research Octane Number (RON) tester according to the ASTM-D4052, ASTM-D6378, and ASTM-D2699 respectively under selected operating conditions. The results obtained revealed that the addition of gasoline–bioethanol blend decreases the RVP value of the fuel blend, whereas the RON and density increase because bioethanol has a high octane rating compared to conventional gasoline, resulting in enhanced gasoline’s performance in internal combustion engines. Overall, the RON of gasohol was enhanced remarkably with the increase in ethanol ratio. [ABSTRACT FROM AUTHOR]

Electric vehicles offer higher acceleration than conventional internal combustion engines due to larger engine torque. The design and placement of battery packs in heavy-duty electric vehicles are still being optimized, as they can affect axle load distributions and consequently impact pavement analysis and design. This study presents a finite element model of a dual tire assembly considering varying load and acceleration conditions to investigate the effect of conventional and electric heavy-duty vehicles on tire–pavement contact forces. Three scenarios for battery pack locations were examined, leading to six loading conditions for both internal combustion engines and electric trucks. The resulting 3D contact forces, compared at a specific line of points along the contact patch and throughout the entire distribution via kernel density estimate, determined that the load increase due to battery location had a much greater impact than the change in torque for both internal combustion engine and electric trucks provided they are at the same rolling condition. Higher loads altered the vertical and longitudinal contact forces and led to a broader contact area. On the other hand, transverse contact forces showed the least variation, although this may differ under cornering scenarios. Finally, a higher slip ratio exacerbated the contact forces in the traveling direction, highlighting the importance of considering rolling conditions in future analyses of pavement damage caused by heavy-duty electric vehicles. Practical Applications: Truck loading usually governs pavement design, layer thicknesses, and corresponding materials while considering local environmental conditions. For flexible pavements, in particular, the details of the distribution of the forces at the tire–pavement interface play a significant role in driving failure near the pavement surface. As the electrification of heavy-duty truck platoons becomes a reality, it is paramount for pavement engineers to quantify the effect of the torque and battery location from electric trucks on contact forces and evaluate its impact on flexible pavements—this paper provides such quantification. The study found that battery location, rather than increased torque, is the controlling variable for the electric trucks due to increased load influence on vertical contact forces. [ABSTRACT FROM AUTHOR]

Automotive radiators are primarily utilized in vehicles to dissipate the heat generated by the engine block into the surrounding. Utilizing coolants with superior thermophysical properties reduces the engine power consumption and improves the cooling engine performance. Comprehending the correlation between coolant characteristics and its thermohydraulic behavior is essential for advancing this innovative cooling technology. This investigation introduces a detailed parametric study of an automotive radiator using diversified coolant mixtures. Ethylene glycol (EG)/water mixtures, namely, (40:60), (50:50), and (60:40) are utilized as a coolant. The influences of the operational mechanism parameters, that is, inlet coolant temperature, intake air temperature, airflow rate, coolant flowrate, and coolant mixture ratio on the effectiveness, heat transfer, and fluid flow characteristics of the radiator are investigated. A thermohydraulic coupled model, based on the effectiveness‐NTU and thermal resistance theories, are developed for simulation of the investigated radiator. The outcomes revealed that the heat transfer rate is more significantly influenced by the inlet temperatures of the coolant and air than by the flowrate. Findings reveal optimal conditions for radiator design to be a coolant mixture of (40 EG:60 Water), coolant mixture Reynolds number of 1087.5, air Reynolds number of 2175, 11°C air‐intake temperature, and 94.25°C coolant mixture temperature for engine cooling maximization. The findings also indicated optimum mixture yielded the maximum advantage ratio (AR) and heat transfer with lowest pumping power, which achieved 7.94% and 19.30% higher AR compared to (50:50) and (60:40) mixture solutions, respectively. From energy consumption reduction prospective, the optimal EG/water coolant mixture results in a reduction in pumping power by 25.11% and 49.77%, compared to the (50:50) and (60:40) mixtures, respectively, under the same optimal operating conditions. Conclusively, the optimized automotive radiator design explored in this study offers a promising approach to improving vehicle technology and increasing cooling efficiency in internal combustion engines. [ABSTRACT FROM AUTHOR]

The battery electric vehicle (BEV) is one of the viable alternatives to conventional internal combustion engine vehicles (ICEV), and it is promoted to reduce greenhouse gas emissions from road transportation. However, the long charging time and insufficient charging facilities lead to "range anxiety", inhibiting the development of BEVs. Wireless charging (WC) technology has begun to be applied to BEV, helping achieve dynamic recharging when vehicles move on the roadway. An adequate deployment of WC facilities allows BEV travelers to complete trips without needing to stop for recharging. Thus, the WC facility location decision is an essential optimization problem to solve before the technology matures and the facilities are installed. As the vehicle dynamics, such as speed and acceleration, depend on the traffic state, the energy consumption is also dynamic. The deployment of WC facilities based on constant speed and energy consumption may not satisfy the charging needs, and energy stored in the battery can even run out during the trip. Microscopic traffic dynamics are considered in the location optimization problem of the WC facility by introducing a car-following simulation. At a given BEV battery capacity and WC facility number, the shortest length of each facility allowing no-stopping recharging is calculated by the bisection method. With an increase in BEV demand, the societal cost (including both BEVs and WC facilities) increases, but BEV battery capacity reduces, and both WC facility number and length rise based on the optimization method. Similar tendencies emerge even if the drivers have heterogeneity of aggressive or nonaggressive driving behavior. Policy implications (including WC facility replacement and renovation, financial support, safety-driving advertisements, and legal punishment policies) are proposed to promote the development of WC facilities. Our research outcomes can provide a logical design framework for commercializing and deploying the WC system and further reduce the greenhouse emissions of the transport industry by increasing the penetration rate of electric vehicles. • The wireless charging facility location problem in the context of microscopic traffic dynamics is studied. • The wireless charging facility location model on one road considering traffic dynamics is proposed. • The policy implications are proposed to promote the development of WC facilities. [ABSTRACT FROM AUTHOR]

The piston is one of the most essential parts of an internal combustion engine. Direct adjustment of the piston-cylinder clearance, i.e., oil-film thickness between the piston skirt and the cylinder liner, in designs, repairs, and engine conversions, as well as indirectly through mode selection, lubrication, and cooling regimes in engine operation, are necessary to improve the efficiency of its operation. Directly measuring the piston-cylinder clearance in the firing engine is extremely difficult, requiring complex equipment and test benches, but it is difficult. The article presents the theoretical basis and results of converting the original piston of the YAMZ-236 engine to a piston with an oval-barrel profile, using the finite element method in ANSYS 17.2 software to calculate the interaction of the original piston-cylinder pair and the piston-cylinder pair with the modified piston to determine the piston-cylinder clearance, as well as strike out about the effect of using oval- barrel pistons on a particular engine. In the firing engine, the thermal gap of the original piston crown with the cylinder has a negative value, indicating that the original piston-cylinder pair has no gap at the piston crown. The oval-barrel profile of the piston improved the lubrication, reducing the risk of jamming, and reducing noise, friction. [ABSTRACT FROM AUTHOR]

The increasing interest in ammonia as a carbon-free fuel for internal combustion engine applications still faces many challenges. The main barriers to overcome are the high autoignition temperature of ammonia and emissions. Porous medium applications for controlling combustion zone temperature and ignition time reduction have shown their merits in combustion systems. This work examines the effects of using a porous medium in the combustion process of an ammonia-fueled compression ignition engine with a thermodynamic two-zone model. The porous medium is located in the head of the engine cylinder, and the fuel mass is injected into the porous medium before entering the cylinder volume. The combustion in the porous medium region occurs in a constant-volume process. The model uses detailed combustion mechanisms to acquire accurate results. In each calculation timestep, the species concentration, in-cylinder gas temperature, and pressure are updated, and the temperature of the porous medium solid structure is obtained by solving the heat transfer correlations. The results show that applying the porous medium promotes ammonia combustion as the sole fuel in a conventional diesel engine. It reduces the ignition delay time and peak combustion temperature. The intake air temperature and pressure, initial gas temperature in the porous medium volume, injection timing strategies, the initial temperature of the porous medium solid structure, the porous medium porosity, and its material can be used to control the ignition delay time and emissions of the ammonia combustion. [ABSTRACT FROM AUTHOR]

The article discusses the United Auto Workers' (UAW) decade-long struggle to unionize Volkswagen's Chattanooga Assembly Plant, culminating in a victory in 2024 after two previous failed attempts in 2014 and 2019. The UAW's 2014 campaign was marked by strategic missteps and under-resourcing, while the 2019 campaign showed modest improvements but failed to secure victory. The transformative changes within the UAW, including democratic reforms and rank-and-file insurgency, led to a successful campaign in 2024, following a stand-up strike and a shift in organizing strategy towards simultaneous campaigns at multiple sites. Despite a subsequent defeat at Mercedes in Alabama, the UAW's victories at Volkswagen and with the Big Three signal a new path forward for the union in organizing efforts. [Extracted from the article]

• Impacts of LFG impurities and oil additives on deposit formation in engine combustion chamber. • Role of organometallic compounds containing S, Si, Sb, Sn, and P in deposit formation. • Cross-sectional analysis to reveal non-uniform elemental distribution in engine deposits. • Impact of deposit formation in engine combustion chamber on the deterioration of lube oil quality. • Identifying the most effective mechanisms contributing to deposit formation in LFG engine. Combustion chamber deposits adversely affect the operating performance of gas engines. In this study, the elemental composition of deposit samples collected from the inner surface of combustion chambers in gas engines across three different facilities was examined using various methods. The proportional changes in metal oxides along the internal cross-sectional surfaces of the deposits were examined to depict the deposit formation process from beginning to end. Additionally, the study investigated the identification of metals accumulated in the engine oil, their contribution to deposit formation, and the accumulation mechanisms of metal oxide nanoparticles on the engine's interior metal surfaces. The main elements identified in the deposits from the Odayeri and Kömürcüoda facilities were Si, S, and Ca, whereas deposits from the Dilovası facility contained Si and Sb. These major elements, identified by SEM-EDS, were confirmed through XRF analysis. XRD analysis further confirmed the presence of Ca and S as CaSO 4 crystals in the deposits. Ca originates from additives used to increase the total base number of engine oil and control the corrosive effects of landfill gas. It has been determined that silicon accumulates in engine oil over time. An important finding is that metal oxides in the combustion chamber primarily accumulate through impaction, sticking, and thermophoresis mechanisms. [ABSTRACT FROM AUTHOR]

Aircraft gas turbine engines produce Particulate Matter (PM) emissions that have been linked to human health and climate issues, leading to the introduction of regulatory sampling and measurement standards for nonvolatile PM (nvPM) by the International Civil Aviation Organization (ICAO). Due to the significant nvPM losses within the prescribed sampling systems, loss corrections are used. Currently, based on sampling assumptions, electrostatic losses are not included in the standardized loss tool, as it is estimated to account for less than 3% of the total nvPM loss. This study experimentally investigated electrostatic loss of unipolar, bipolar, and naturally charged salt, silver, and carbon black particles at sizes (4–150 nm) and through sampling tubes representative of aircraft nvPM sampling. A unipolar and bipolar charger, along with a tandem SMPS-CPC measurement methodology, were employed to explore the impacts of tube material, Reynolds Number, tube diameter, residence time, and particle charge state on electrostatic loss. Minimal electrostatic loss was measured for conductive stainless steel and extensively bedded-in (above 300 h) carbon-loaded PTFE. However, an additional loss of up to 50% was observed within new cPTFE (with approximately 30 min of bedding-in), attributed to precipitation in an electric field. Furthermore, it was found that electrostatic dispersion could cause significant additional losses at high concentrations of unipolar or bipolar asymmetrically charged particles. Therefore, further research is required to determine the charge state of aircraft nvPM across different aircraft engine conditions to determine if unquantified electrostatic loss could occur within the probe section of the sampling system. [ABSTRACT FROM AUTHOR]

The potential of electric vehicles (EVs) to support the decarbonization of the transportation sector, crucial for meeting greenhouse gas reduction targets under the Paris Agreement, is obvious. Despite their advantages, the adoption of electric vehicles faces limitations, particularly those related to battery range and charging times, which significantly impact the time needed for a trip compared to their combustion engine counterparts. However, recent improvements in fast charging technology have enhanced these aspects, making EVs more suitable for both daily and long-distance trips. EVs can now deal with long trips, with travel times only slightly longer than those of internal combustion engine (ICE) vehicles. Fast charging capabilities and infrastructure, such as 350 kW chargers, are essential for making EV travel times comparable to ICE vehicles, with brief stops every 2–3 h. Additionally, EVs help reduce noise pollution in urban areas, especially in noise-saturated environments, contributing to an overall decrease in urban sound levels. However, this research highlights a downside of DC (Direct Current) fast charging stations: high-frequency noise emissions during fast charging, which can disturb nearby residents, especially in urban and residential areas. This noise, a result of the growing fast charging infrastructure, has led to complaints and even operational restrictions for some charging stations. Noise-related disturbances are a significant urban issue. The World Health Organization identifies noise as a key contributor to health burdens in Europe, even when noise annoyance is subjective, influenced by individual factors like sensitivity, genetics, and lifestyle, as well as by the specific environment. This paper analyzes the sound emission of a broad sample of DC fast charging stations from leading EU market brands. The goal is to provide tools that assist manufacturers, installers, and operators of rapid charging stations in mitigating the aforementioned sound emissions in order to align these infrastructures with Sustainable Development Goals 3 and 11 adopted by all United Nations Member States in 2015. [ABSTRACT FROM AUTHOR]

Densely populated urban megacities, such as the Metropolitan Area of Mexico City, face the ongoing deterioration of air quality. Emissions from industrail factories and internal combustion vehicles are the main sources of pollutants. We have evaluated different transition trends from internal combustion engine vehicles as bus, truck and van, and motorcycle to electric vehicles through 2050. The total vehicle growth follows a second-degree polynomial trend. Bus growth exhibits a linear trend. Truck and van growth display a second-degree polynomial trend. Motorcycle growth also follows a second-degree polynomial trend. We found that the most significant reductions in transportation emissions are observed in C O 2 , followed by N O x , volatile organic compound (VOC), and particulate matter, with light and heavy vehicles being the primary contributors to total emissions. Mexico City serves as a pilot laboratory where both the challenges and potential solutions to an issue affecting millions of citizens can be observed. If proven effective and practical, these solutions could be applied to other megacities. [ABSTRACT FROM AUTHOR]

The transition to sustainable mobility is one of the most pressing and complex challenges for the automotive industry, with impacts that extend beyond the mere reduction of emissions. Electric vehicles, while at the center of this evolution, raise questions about the consumption of natural resources, such as lithium, copper, and cobalt, and their long-term sustainability. In addition, the introduction of advanced technologies, including artificial intelligence (AI) and autonomous systems, brings new challenges related to the management of components and materials needed for their production, creating a significant impact on supply chains. The growing demand for electric and autonomous vehicles is pushing the industry to rethink production models, favoring the adoption of circular economy principles to minimize waste and optimize the use of resources. To better understand the implications of this transition, this study adopts a multiple case study methodology, which allows in-depth exploration of different contexts and scenarios, and analysis of real cases of dismantling and recycling of internal combustion engines (ICEs) and electric vehicles (EVs). The research includes a financial simulation and a comparison of revenues from the dismantling of ICE and EV vehicles, highlighting differences in the value of recycled materials and the effectiveness of circular economy practices applied to the two types of vehicles. This approach provides a detailed overview of the economic benefits and challenges related to the management of the end of life of vehicles, helping to outline optimal strategies for a sustainable and cost-effective future in the automotive sector. [ABSTRACT FROM AUTHOR]

Vehicle system models can be roughly divided into two categories, dynamic and steady-state (or quasi-steady-state) models, and can be applied to evaluate vehicle transient performance such as vehicle longitudinal and lateral dynamics, as well as energy economies like fuel or electricity consumption. This paper reviews various energy consumption models for automotive systems, focusing on component- and vehicle-level models. As the foundation to calculate the energy consumption, powertrain component models of three main vehicle types (internal combustion engine (ICE) vehicles, electric vehicles (EVs), and hybrid vehicles) are reviewed with their key components, including internal combustion engines, electric motors, and batteries. Three types of vehicle energy consumption models are explored according to their interpretability: white-box, black-box, and grey-box models. Optimizing vehicle energy usage based upon a vehicle energy consumption model is reviewed from the aspects of eco-driving and eco-routing problems at the end of the paper. Eco-driving research primarily selects models focusing on transient performance; whereas eco-routing focuses on steady-state or quasi-steady-state conditions to balance the needs of model accuracy and calculation efficiency for real-time applications. This review aims to guide model selection and inspire future applications of energy consumption models for advancing sustainable automotive technologies. [ABSTRACT FROM AUTHOR]

In this article, the results of an experimental investigation and a 1D modeling activity on the steady-state performance of a wastegated turbocharger turbine for spark ignition engines are presented. An experimental campaign to analyze the turbine performance for different waste-gate valve openings was conducted at the test bench for components of propulsion systems of the University of Genoa. Thanks to the experimental activity, a 1D model is developed to assess the interaction between the flow through the impeller and the by-pass port. Advanced modeling techniques are crucial for improving the assessment of turbocharger turbines performance and, consequently, enhancing the engine–turbocharger matching calculation. The initial tuning of the model is based on turbine characteristic maps obtained with the by-pass port kept closed. The study then highlights the waste-gate valve behavior considering its different openings. It was found that a more refined model is necessary to accurately define the mass flow rate through the waste-gate valve. After independently tuning the 1D models of the turbine and the waste-gate valve, their behavior is analyzed in parallel-flow conditions. The results highlight significant interactions between the two components that must be taken into account to reduce inaccuracies in the engine-turbocharger matching calculation. These interactions lead to a reduced swallowing capacity of the turbine impeller. This reduction has an impact on the power delivered to the compressor, the boost pressure, and, consequently, the engine backpressure. The results suggest that methods generally adopted that consider the by-pass valve and the turbine as two nozzles working in parallel under the same thermodynamic condition could be insufficient to accurately assess the turbocharger behavior. [ABSTRACT FROM AUTHOR]

Iron–nickel-based superalloy is an ideal substitute for the expensive Inconel 625 and Inconel 751 alloys. To elucidate the evolution of the microstructure and properties of Ni30 alloy under different thermal treatment conditions, a systematic study was conducted on the microstructural transformation of the alloy's strengthening γ′ phase following solution treatment and aging, as well prolonged exposure at 750 °C, and the oxidation behavior of the Ni30 alloy was examined. During prolonged thermal exposure, grain growth occurs mainly in the initial stage, and after 200 h, the prolonged exposure time leads to a significant coarsening of γ′ precipitates, whose area fraction increases by more than 10 times compared to their unaged state. After 100 h of aging, the alloy reaches a peak tensile strength of 1270 MPa and a yield strength of 820 MPa; after 2000 h, the alloy maintains a relatively high strength with a slight decrease in ductility. The oxidation kinetic curve of Ni30 alloy follows the quasi-parabolic oxidation law at 750 °C, and its oxidation rate is consistently lower than 0.1 g·m−2·h−1 throughout the whole oxidation process, which indicates that it has excellent oxidation resistance. The external oxide layer of Ni30 alloy shows a bilayered structure, and no obvious surface porosity or flaking of oxidation products were observed throughout the high-temperature oxidation test. This study not only contributes to the improvement of material properties, but also promotes innovation and development in the field of high-temperature engineering applications that will help to meet the increasingly stringent requirements of high-temperature working environments. [ABSTRACT FROM AUTHOR]