Experimental analysis of performance and emissions of hydrous ethanol in internal combustion engine and multi-objective optimization based on ABC-ANN-NSGAII

Quantifying fuel consumption in internal combustion engine through pollutant emission analysis: Interlaboratory comparison

Adaptive air-fuel ratio control for hydrogen internal combustion engines

A methodology for boundary condition optimization in 3D-CFD of internal combustion engines

Thrust characteristics of the OSA-3 aircraft propulsion system with a two-stroke piston internal-combustion engine for selected propeller configurations

ABSTRACT Pre‐chamber jet ignition (JI) is a transformative technology enabling stable ultra‐lean combustion and enhanced thermal efficiency in hydrogen‐fueled internal combustion engines. This narrative review synthesizes decades of research on JI systems, from foundational hydrogen‐assisted JI concepts to modern applications synergized with direct injection (DI) and turbocharging. We critically analyze key geometric parameters governing pre‐chamber design, including volume ratios and nozzle configurations, and their impact on jet dynamics, heat loss, and combustion stability. The integration of JI with DI is shown to mitigate hydrogen's combustion challenges (e.g., knock, NOx) while enabling throttle‐less load control. Furthermore, electric turbocharging eliminates lag and enhances power density, while additive manufacturing facilitates near‐adiabatic ceramic pre‐chambers to minimize thermal losses. This review further explores the comparative advantages of active versus passive JI strategies and examines synergistic technologies such as electric turbocharging. A dedicated case study on rotary valve engines contextualizes critical design trade‐offs. Finally, we evaluate the transformative potential of additive manufacturing in fabricating near‐adiabatic pre‐chambers, which promise significant reductions in heat loss and gains in thermal efficiency. This review underscores JI's pivotal role in unlocking hydrogen's potential as a zero‐carbon fuel, highlighting pathways toward 45%–50% brake efficiency and near‐zero emissions.

Shipping is one of the most energy-efficient modes of transport, and its carbon emissions are second only to road transportation. Applying carbon capture technology on vessels using carbon-based fuels not only meets the Carbon Intensity Indicator (CII) requirements proposed by the International Maritime Organization (IMO) but also avoids the modification of ship internal combustion engine power systems, thereby reducing investment costs. However, ship-based carbon capture technology still faces problems such as unclear process parameters, high energy consumption, and limited research on optimal performance regulation under different operating conditions. Aiming at the ship-based carbon capture system using Monoethanolamine (MEA) solution as an absorbent, this paper focuses on reducing operational energy consumption, comparatively analyzes the development of carbon capture technology and ship-based carbon capture processes, and proposes improvement measures for technical research.

This paper focuses on alternatives to the CAFC-NEV credits policy in the automotive industry of China. It considers a dual-channel supply chain consisting of a manufacturer and a retailer that can simultaneously produce and sell new energy vehicles (NEVs) and internal combustion engine vehicles (ICEVs). Differential game theory is employed to explore dynamic optimal decisions under CAFC-NEV credits and carbon credit policies. The results suggest that the strategies combining CAFC-NEV credits and carbon credit policies are equivalent to a single CAFC-NEV credits policy. Therefore, implementing the carbon credit policy on the basis of the CAFC-NEV credits policy does not affect the increase in NEV range. If the NEV credit score is below a certain threshold, the carbon credit policy will result in a higher range increase and brand goodwill of NEV. In the transition process of implementing the carbon credit policy based on CAFC-NEV credits and subsequently canceling the CAFC-NEV credit policy, the profits of supply chain members change slightly. The findings provide a theoretical basis for the timely exit of the CAFC-NEV credits policy.

Hydrogen vehicles in the green energy transition: A systematic review of internal combustion engine and fuel cell technologies, energy system integration, and AI application

Decarbonizing transportation through electric vehicles: A life cycle perspective across China, Europe, and the USA.

In-cylinder hydrogen concentration effects on lubricant-surface interactions and tribofilm formation in hydrogen internal combustion engines

Experimental investigation on high-pressure gas jet characteristics under high backpressure conditions for hydrogen internal combustion engines

The need for energy and environmental concerns are driving the demand of efficient, sustainable fuels as transportation fuels. This article is an inquiry on energy efficiency improvement in internal combustion engines using alternative fuels under the scenario of Bangladesh. A Quantitative research design was adopted, primary data were obtained from 400 respondents through a structured questionnaire developed by applying Cochran’s sample size formula. The interviewers were vehicle owners, operators, drivers, and mechanics with first hand practice in fuel consumption and engine performance. Statistical analysis was performed by SPSS and descriptive statistics were utilized to analyze trends and associations. The results show that biofuels offer good options to improve fuel economy, engine performance and reduce pollutants when compared with conventional petroleum fuels. The engine optimization strategies include appropriate tuning and maintenance which were also identified as significant factors for achieving efficiency results. However, the research also highlighted some bottlenecks, such as high conversion costs, inadequate refueling infrastructure, fuel quality variation and a shortage of qualified repairmen that may limit the widespread use. The paper finds that there is potential for alternative fuels to contribute towards sustainable transport and energy efficiency in Bangladesh. Policy support, infrastructure development, technical capacity building, and regulatory oversight are suggested to smooth the transition towards cleaner fuel technologies and sustainable environment in the long run.

This paper proposes a power architecture for a Compound-Wing Unmanned VTOL to supply power during the hovering state. To enhance the hovering efficiency of the UAV while considering the cruising efficiency, the layout structure of a traditional Compound-Wing Unmanned VTOL is optimized. A high-power-density hybrid-power range-extender using an ICE (internal combustion engine) suitable for the Compound-Wing Unmanned VTOL is designed. The engine electronic control unit (ECU) suitable for the range-extender is presented by using a locally linearized state-space equation and LQR (Linear-Quadratic Regulator). Simulation experiments, ground running tests, and flight tests have been conducted to verify the performance of the Compound-Wing Unmanned VTOL and its power architecture.

The effect of ozone-air pretreatment (OAP) on the performance and environmental characteristics of the 153FMI gasoline carbureted engine, Hyundai Tuscon III D4HA/Series R, and Komatsu 4D92L-1B59B diesel engines was investigated in this paper. The experiments were conducted using acoustic analysis of engine operation and exhaust smoke analysis. The tests were conducted at a temperature of 25°C and a relative air humidity of 47%, including engine operation on AI-92 gasoline and summer diesel fuel under various modes: idling, accelerating, and running at nominal speed. Initially, a test start and warm-up of the engine were performed without ozone supply. Then, a repeated start was performed and performance characteristics were recorded with OAP introduced into the system. The use of OAP in the 153FMI gasoline engine led to a significant improvement in the starting process. Starting time was reduced, on average, from 8 strokes (without OAP) to starting from the first crankshaft revolution. In idle mode, stabilization of operation was observed: fewer misfires and a more uniform acoustic signal. The effect of ORP on the Komatsu 4D92L-1B59B diesel engine resulted in reduced exhaust smoke. Average smoke (based on ten measurements) decreased from 5.7% (without ORP) to 2.3%. Furthermore, improved diesel engine performance and increased throttle response were observed. The obtained results demonstrate the positive impact of ORP on the performance of internal combustion engines. Analysis showed that the use of ORP promotes more efficient combustion of the airfuel mixture. Further research is aimed at assessing the impact of ORP on power performance, environmental performance (CO, CH, NOx emissions), fuel efficiency, and optimizing ozone injection parameters.

Recent years have shown Porsche Synthetic Fuels (POSYN) as one promising and quick solution to be used in both existing and new-generation internal combustion engines (ICEs) to immediately contrast the CO 2 emissions. Nevertheless, to make these fuels efficient and effective for ICE applications, extensive testing is needed to evaluate the fuel performance and its impact on tailpipe emissions; numerical simulations (both 1D and 3D) can provide relevant support to reach the target in a faster and economically feasible way, providing guidelines for the design of eFuels and their use. An accurate and reliable modeling framework, able to mimic the chemical and physical characteristics of the fuels for a given set of operating conditions, is therefore mandatory to support the development process. The definition of a fuel surrogate is crucial to integrate the relevant properties in the 3D-CFD modeling framework. In this work, a methodology for the calculation of LFS (Laminar Flame Speed) and IDT (Ignition Delay Time) of different fuels is developed and applied to compare the characteristics of two different POSYN fuels with a conventional RON 98 gasoline by using 0D/1D detailed chemical kinetics simulations. The methodology relies on a proper definition of the composition of a six-component fuel surrogate and on the critical selection from the literature of a suitable chemical kinetics mechanism. The methodology is then applied to calculate IDTs and LFSs on a wide set of engine-relevant conditions, allowing for comparing the fuels’ behavior, paving the way for more detailed 1D and 3D-CFD studies. Finally, the LFS calculations of free-aromatics gasoline showed a faster flame speed in a range between 3% and 6% compared to the conventional one at engine-like conditions. Instead, IDTs, according to similarities in RON/MON, showed overall similar output and peculiar NTC behavior when MTBE is present.

Nanoparticles (NP) in the sub-micrometer measuring range are invisible. NPs from combustion processes, consisting of carbon, metal and ash nuclei and organic substances, enter the human organism through the olfactory nerves and lungs, where they can have various effects (toxic, carcinogenic, mutagenic), some of which are long-lasting (chronic). These invisible nanoparticles were identified in the second half of the last century. Since then, a great deal of research has been carried out in various fields, and nanofiltration has demonstrated and realised ways of efficiently removing nanoparticles. The greatest progress has been made in the aftertreatment of exhaust gases from combustion engines. Nevertheless, further efforts are needed here, as in other areas such as indoor and outdoor air pollution control. The authors have been involved in important stages of these developments and, in this article, they attempt to provide a brief review and a desirable outlook, along with a few examples. In summary, it can be said that all types of engines and numerous other anthropogenic sources emit harmful nanoaerosols. During the pandemic, it was proven that nanofiltration used for exhaust gas aftertreatment in engines effectively eliminates bio-nanoaerosols, i.e. viruses and larger pathogens such as bacteria, fungi, allergens and others. We are all constantly surrounded and permeated by nanoaerosols and must live in symbiosis with them. It is therefore advisable for society to gain a better understanding of this issue, take it seriously and be even more concerned about the quality of the air surrounding the general population.

Regardless of the class of passenger car, manufacturer, or type of internal combustion engine, vehicle owners strive to ensure the longest possible period of reliable engine operation. The reliability and performance of an internal combustion engine are key indicators of its quality and prestige. Numerous research and development studies have focused on optimizing piston design and identifying the causes of piston failure. However, to better understand degradation mechanisms and trends in modern piston design, it is necessary to investigate the phenomena affecting the piston during typical engine service life. Thermomechanical stresses, friction, elevated and fluctuating temperatures, and contaminants all contribute to piston wear and reduce its service life. In this study, a new aluminum piston was compared with a piston extracted from an engine after approximately 200,000 kilometers of operation. The influence of engine operating time on piston surface condition, hardness, microstructure, and surface quality was analyzed. These parameters provide insight into the impact of friction and thermal loads on piston wear. Based on the investigations, the influence of piston operating time on surface degradation and changes in the mechanical properties of the piston material was determined. Furthermore, areas most susceptible to long-term loads and exhibiting the highest wear were identified. The results enable identification of piston regions requiring reinforcement or design optimization to minimize the risk of damage from prolonged engine operation.

Introduction . This article presents a methodology for conducting experiments as well as their results which show the relationbetween the signal range magnitude of the current consumed and the rate of increase in engine oil pressure, the coolant temperature of a power plant diesel engine operating at low temperatures. The relevance of this study is determined by the need to reduce the complexity and time of technical diagnostics of construction equipment, in particular a bulldozer, which is of special importance in the field conditions of the Far North. Current consumption studies have been focused onpositive temperature ranges (from 40 to 90 degrees Celsius). According to the authors’observations,when the ambient temperature changes, the diagnostic parameter under study (the amount of current consumed) is characterized by instability, reading ambiguity and requires correction. The need to warm up the diesel engine of the power pack increases the waiting time necessary for diagnostics. Starting failures of a power pack internal combustion engine lead to the violation of conditions for leak tightness diagnostics of the space above a piston by measuring the amount of current consumed. Therefore, the aim of the study is to determine relationship between the amount of current consumed by the starter and the rate of increase in engine oil pressure, the coolant temperature of a power pack diesel engine operating at low temperatures. Materials and methods . This section presents the methodology and the results of the experiments. The experiments were carried out with a 6-cylinderdieselinlineengine of the power pack of the Shantui SD 22 bulldozer in the field conditions at subzero temperatures. Results. Based on the analysis of experimental data, mathematical dependences were constructed between the magnitude of the signal range of the current consumed by the power pack engine and the rate of increase in engine oil pressure, and the coolant temperature. Discussion and conclusion . Expanding of the functionality of the relative compression method reduces labor content of diagnostic operations included in maintenance No.3(which is carried out every thousand operating hours) for Komatsu D-355A bulldozer by 8%,and labor content of diagnosing the diesel engine power pack itself is reduced by17%.The research undertaken makes it possible to introduce correction coefficients and thereby to ensure the specified measurement accuracy and the reduced complexity and time,toimprove the controllability of technical diagnostics of power plant diesel enginesin construction machinery.

Increasing the efficiency and durability of the piston compressors, pumps, internal combustion engines, etc. directly depends on the correct calculations and designing of these elements. Using ANSYS software, simulation and stress analysis are performed on the basis of the 405GP15/70 and ARIEL heavy-duty balanced opposed piston compressors used in the Caspian Sea - Black Sea Region, providing numerical validation of thermal and structural behavior under operational conditions. Investigation of complex problems with respect to stresses, and thermodynamics phenomena in the piston machines, and oil and gas pipelines gives the opportunity to solve the problems of increasing the durability of these machines and pipelines. Increasing the reliability and durability of piston machines therefore meets the current industrial demand for minimizing environmental impacts during the exploitation and transportation of oil and gas resources. The novelty is characterized by new theoretical methods for the determination of forces of gas pressure in cylinders of reciprocating machines taking into account the wear processes and the clearances in kinematic couples of crank-piston mechanisms. The reliability of the received scientific results is provided with the correctness of the statement of tasks and decisions on the basis of laws of physics, mechanics and thermodynamics. The results of the investigation are generalized for any piston machines used in the oil and gas industry. The results of the investigation can be useful for the design and exploitation of transregional pipelines and environmental problems.