Performance Of Internal Combustion Engines Research Articles

Prediction of Efficiency, Performance, and Emissions Based on a Validated Simulation Model in Hydrogen–Gasoline Dual-Fuel Internal Combustion Engines

This study explores the performance and emissions characteristics of a dual-fuel internal combustion engine operating on a blend of hydrogen and gasoline. This research began with a baseline simulation of a conventional gasoline engine, which was subsequently validated through experimental testing on an AVL testbed. The simulation results closely matched the testbed data, confirming the accuracy of the model, with deviations within 5%. Building on this validated model, a hydrogen–gasoline dual-fuel engine simulation was developed. The predictive simulation revealed an approximately 5% increase in overall engine efficiency at the optimal operating point, primarily due to hydrogen’s combustion properties. Additionally, the injected gasoline mass and CO₂ emissions were reduced by around 30% across the RPM range. However, the introduction of hydrogen also resulted in a slight reduction (~10%) in torque, attributed to the lower volumetric efficiency caused by hydrogen displacing intake air. While CO emissions were significantly reduced, NOₓ emissions nearly doubled due to the higher combustion temperatures associated with hydrogen. This research demonstrates the potential of hydrogen–gasoline dual-fuel systems in reducing carbon emissions, while highlighting the need for further optimization to balance performance with environmental impact.

Innovative Metal Coating Strategies for Enhanced Engine Performance and Emission Mitigation in Internal Combustion Engines: A Comprehensive Review

This comprehensive work addresses the pressing environmental concerns associated with the automotive industry`s expansion and its reliance on fossil fuels. Focusing on the pivotal role of energy in vehicle propulsion, the paper explores diverse energy utilization methods and their conversion into mechanical energy for mobility. While chemical energy currently powers most vehicles, it contributes to detrimental emissions, necessitating innovations to enhance fuel quality, engine design, and materials. The research emphasizes refining the performance, and life cycle, and minimizing exhaust emissions of internal combustion engines. A key focus of this paper is the proposal of a novel approach that advocates the application of coatings to the combustion surface and catalytic converter to bolster engine performance and curtail emissions. The researchers highlight the efficacy of metal coatings, including thermal barrier coatings and catalytic coatings, presenting a comprehensive overview of experimental research articles endorsing the positive impact of metal coating strategies. These coatings aim to enhance combustion dynamics, manage thermal stresses, and optimize catalytic converter efficiency. In this technical paper offers valuable insights for researchers and engineers committed to mitigating the environmental impact of the automotive industry. It underscores the critical need for optimizing engine performance and minimizing emissions, with a specific emphasis on the promising potential of metal coating technologies to significantly contribute to these overarching objectives.

Organic Rankine Cycle System Design by Utilizing The Waste Heat of Internal Combustion Engine Based on Numerical Simulation

Abstract Most of the energy supply for today’s human activities still comes from fossil energy. Energy based on fossil fuels can cause an increase in greenhouse gas (GHG) emissions. Therefore, increasing the efficiency of energy conversion systems based on fossil fuels is necessary to mitigate pollutant emissions. The internal combustion engine (ICE) is one energy conversion machine that still consumes fossil energy to work in the transportation sector. Losses during internal combustion engine operation result in reduced engine thermal efficiency. Exhaust gas heat loss is one of the relatively significant losses. It leads to the waste of heat, which could be utilized and converted into valuable energy in the form of electrical energy that the engine can use, resulting in a considerable amount of primary fuel that could be saved. An organic Rankine cycle (ORC) system is considered in this analysis as a heat recovery unit from the Diesel ICE. The Aspen Plus simulation software was chosen to design the system consisting of an ORC unit integrated with a Diesel ICE unit. The working fluid for ORC used in this analysis is R-141B, R-123, and R-245fa. The simulation results show that the heat the ORC unit receives from the ICE via turbocharger is around 366 °C. Thus, the system has a thermal efficiency of 11.11% when using R-141B as the working fluid, 8.41% if R-123 as the working fluid, and 6.63% when using R-245fa as the working fluid. This study also obtained a condenser design as part of the ORC unit. The condenser can be considered a plate heat exchanger, with 53 plates needed to support the process.

Effective utilization of waste plastics and ammonia as biodiesel to assess performance and emission

Purpose This study aims to examine the environmental effects of plastic waste on the atmosphere and its implications for disaster waste management. It focuses on using ammonia, pyrolyzed plastic oil and the effectiveness of alumina nanoparticles as a catalyst. Design/methodology/approach The research explores different combinations of conventional diesel and nano Al2O3 derived from pyrolyzed plastic oil (ranging from P10 to P40). Critical performance metrics evaluated include brake mean effective pressure (BMEP), brake specific fuel consumption, brake thermal efficiency and emissions of CO2, CO and NOx. The study specifically investigates the impact of adding 50 ppm of Al2O3 nanoparticles to these blends. Findings The findings indicate that using blended fuels with nanoadditives significantly lowers pollution. Specifically, the P30 blend with 50 ppm of Al2O3 nanoparticles greatly reduced CO emissions. Additionally, the same blend reduced NOx emissions and CO2 emissions. The P30 mix showed improved BMEP and brake thermal efficiency due to its density, calorific value and viscosity (6.3 bar). The P30 blend exhibited higher thermal efficiency due to decreased heat loss, whereas conventional diesel demonstrated the best mechanical efficiency due to its longer ignition delay. Originality/value This study highlights the potential of using Al2O3 nanoparticles and pyrolyzed plastic oil to reduce emissions and enhance the performance of internal combustion engines. It underscores the environmental benefits and implications for disaster waste management by converting plastic waste into useful resources and reducing air pollution.

Investigating the Characteristics of Injecting and Spraying Methanol-Containing Fuel in a Diesel Engine

Introduction. The operation of eco friendly and high-efficiency internal combustion engines is not possible without deep and comprehensive study of using new types of fuels. That is why, forecasting the indicators of injecting and spraying in a diesel engine running on a mixed alcohol-containing fuel, which have a direct effect on the combustion and formation of toxic components and, as a result, on efficiency and eco friendliness, is an urgent scientific task.Aim of the Study. The study is aimed at developing a theoretical basis for calculating the characteristics of injecting and spraying methanol-containing fuel into diesel engine cylinders that allows optimizing its processes.Materials and Methods. There are considered the characteristics of injecting and spraying alcohol-containing fuel in a diesel engine modified to operate on a mixed methanol-containing fuel. There were used the well-known A.S. Lyshevsky dependencies, which fairly reliably reflect the processes of injecting and spraying in diesel engines.Results. The in-depth studies of the basic principles for evaluating the indicators of injecting and spraying standard fuel made it possible to adapt them for fuels of mixed methanol-containing composition and to investigate the dynamics of changes in the duration and speed of injection, the Weber criterion values, the boundaries between the areas of fuel jet forming, droplet size and spraying angle.Discussion and Conclusion. There has been developed a theoretical basis for calcu­lating the characteristics of injecting and spraying methanol-containing fuel that makes it possible to optimize the operation of a diesel engine running on mixed fuel and, as a result, improve its efficiency and eco friendliness. The presented numerically information on the change in the boundaries of the fuel jet forming areas, the size of the droplets and the angle of the spraying cone allows us to reliably determine the basic parameters of spraying of the used mixed methanol-containing fuels, determine the vector of optimization of the mixing processes and gives insight into the promising directions in designing the geometry of combustion chambers, intake ducts, etc.

Impact of Soybean Biodiesel Blends with Mixed Graphene Nanoparticles on Compression Ignition Engine Performance and Emission: An Experimental and ANN Analysis

The extensive use of fuels in power generation plants, industries, and transportation has led to a scarcity of fossil fuels and has contributed to global warming. This has prompted researchers to focus on improving internal combustion engine performance, as the transportation system accounts for 50% of global fuel consumption. Soybean biodiesel plays a vital role in reducing emissions and fuel consumption in engines. In the current work, a blend of soybean oil is used as a biodiesel (B20, B40, and B60), with and without the addition of graphene nanoplatelets (GNPs) examined on a constant-speed compression ignition (CI) engine with respect to pure diesel. The blends are denoted as B20GNP10, B20GNP20, B20GNP40, B20GNP60, B20GNP80, and B20GNP100, according to their proposition of biodiesel and graphene nanoplatelets. Similar blends were prepared for B40 and B60 combinations with similar GNPs concentrations. The prepared blend properties were measured, and good thermophysical properties were found. The trial includes testing the engine emissions and performance at altering loads ranging from 0 to 12 kg for all blends. The artificial neural network (ANN) tool is used to forecast the accuracy of experimental results. Compared to pure diesel, the B60GNP100 blend at 12 kg load condition showed the lowest brake specific fuel consumption at 12.58 % and the highest brake thermal efficiency at 27.13%. Emissions were estimated using a gas analyzer, and the outcomes indicated that the biodiesel blends have controlled levels of CO, CO2, NOx, and HC compared to pure diesel. The ANN model with 99.99% accuracy was developed using experimental data, confirming the accuracy of the experimental results with lower simulation time and cost. Additionally, the B60GNP100 blend yielded better results compared to previous studies.

Tribofilm distribution and tribological analysis of piston ring-cylinder liner interfaces under realistic engine conditions

The study investigates tribofilm distribution and tribology performance on piston ring-cylinder liner surfaces under realistic internal combustion (IC) engine conditions. By examining the effects of load, temperature, and oil film thickness ratio, the research reveals that the tribofilm is significantly greater on the cylinder liner surface compared to the piston ring surface. The findings highlight that a specific excitation pressure is necessary for tribofilm formation. An oil film thickness ratio of 1.8041 is evaluated as an accurate boundary for tribofilm distribution on the cylinder liner surface. These insights provide valuable data for designing piston ring-cylinder liner interfaces and improving IC engine performance.

Development of Free Fatty Acid (FFA) monitoring device for evaluation of oil samples used for biodiesel production

Diversion of oil sources for biodiesel production has been gaining importance to meet the environmental concerns and energy demand. The free fatty acid (FFA) content of the feedstock is a significant factor in biodiesel production. The FFA values determine the complexity of the biodiesel production. Until date, an experimental procedure has been used to determine the FFA concentration of an oil source; this method is dependent on titration, which is a laborious process involving significant volumes of chemicals. Hence, in the present study, an attempt was made to develop a device for the identification of FFA of the oils. Waste cooking oil samples subjected to wide range of cooking conditions like cooking time, temperature, type of food are collected from different food outlets. Subsequently, the composition of oil samples and the variation in their quality were analysed using gas chromatography flame ionization detector (GC – FID). Biodiesel is prepared from the oil samples through transesterification and the impact of FFA and their respective methyl esters in the quality and properties have been investigated. The properties of biodiesel were determined as per ASTM standards. The study was further extended to correlate the properties of biodiesel with the composition of the oil from which it was derived. The analysis evidently proved the dependence of biodiesel properties on the FFA percentage and the composition of the oil. The results have been further substantiated with the performance and emission characteristics of internal combustion engine fuelled with the prepared biodiesel samples.

Diesel Engine Turbocharger Monitoring by Processing Accelerometric Signals through Empirical Mode Decomposition and Independent Component Analysis

In this study, a method for the monitoring of internal combustion engine operation by vibration signals is proposed. The work falls within the context of the increasingly stringent standards relating to the environmental impact of engines and the development of monitoring and control techniques to ensure increased engine performance as well as fuel saving and reduction of pollutant emissions. Experimentation was performed on a turbocharged light-duty compression ignition direct-injection engine. Two monoaxial accelerometers were installed on the engine compressor case, the speed of which has been demonstrated to be closely related to the engine operation. Vibration measurements of the engine compressor case have been processed by combining the Empirical Mode Decomposition technique with Independent Component Analysis and Short Time Fourier Transform to indirectly estimate the turbocharger speed. The obtained traces have been compared to the direct turbocharger velocity measures during the stationary running of the engine (speed and load conditions varied in the complete engine’s range of operation). The results point out the potentiality of the methodology in algorithms devoted to identifying modifications of the combustion development regarding regular operation via indirect turbocharger speed monitoring.

Unveiling the impact of date-specific analytics on vehicle fuel consumption and emissions: A case study of Shiraz city

Understanding the factors affecting internal combustion engine performance is crucial for improving emissions and fuel efficiency in real traffic. This paper investigates the influence of date-specific factors, such as working days and holidays on fuel consumption and emissions of a representative internal combustion engine in the context of Shiraz city. The data was collected by measuring the speed of vehicle on a specific route during peak traffic times on both working days and holidays. The determined route was calculated by a qualitative and quantitative method. K-means clustering and principal component analysis are employed to design representative driving cycles, then combining micro-trips and smoothing them to develop driving cycles. Characteristics of both driving cycles, emissions such as HC, NOx, CO, and fuel consumption were specified under a simulated vehicle model of Peugeot 206 and placed through both real driving cycles by using advanced vehicle simulation software. It has been observed that variations in fuel consumption and emissions between holidays and working days can be attributed to distinct driving patterns and characteristic parameters, such as acceleration, speed, and driving time. Contrary to common assumptions, the study found that fuel consumption was approximately 8 % higher on holidays compared to working days, primarily due to increased driving time and higher average speeds. Moreover, higher acceleration and speed on holidays led to a significant increase in CO emissions (about 36 %) and NOx emissions (about 4 %) compared to working days. However, HC emissions was found to be 27.03 % higher on working days according to lower speed. This study helps in reducing fuel consumption and emissions by uncovering internal combustion engine factors, optimizing driving patterns, and promoting sustainable transport on working days and holidays.

Comparative performance and emission analysis of internal combustion engine and battery electric vehicle under modified Indian drive cycle

This study deals with an analysis of the performance and emissions characteristics of an automotive Compression Ignition Engine Vehicle (CIEV) with 86 kW rated power output fueled with diesel in comparison to a grid based Battery Electric Vehicle (BEV) with 86 kW Electric Motor under the Modified Indian Drive Cycle (MIDC) using the simulation. A novel methodology for undertaking the comparative analysis is developed to assess the CIEV and BEV performance for different scenarios under wide operating conditions. The results indicate that energy consumptions for CIEV and BEV under the MIDC cycle are 2653.1 kJ/km and 416.72 kJ/km. The net effective carbon price during fuel production and vehicle operation is Rs 0.20 per km for CIEV which is 80 % more than Rs 0.11 per km for BEV. A BEV also has an initial carbon debt due to battery production which is 27 times that of CIEV, however, this penalty is easily recovered within a short period against the lower running costs of BEV. The range of the ICE power source is estimated to be 5.85 times that of the EV for MIDC. By increasing the battery capacity five fold, the range of EV can be enhanced, however considerable weight penalty is levied. The levelised cost of transportation for one lakh kilometers was assessed wherein it was found that ICE vehicle expenditure is approximately Rs 25.59 per km against Rs 23.31 per km of BEV.

Ambient Temperature Effects on Energy Consumption and CO2 Emissions of a Plug-in Hybrid Electric Vehicle

The ambient temperature affects the operation of different powertrain systems, including electric, hybrid electric, and internal combustion engines. This study investigated the effect of the ambient temperature on the energy consumption and CO2 emissions of a plug-in hybrid electric vehicle running in different powertrain modes. The vehicle was driven for 4150 km following a selected route 199 times in different powertrain modes and in different ambient temperatures ranging from −24 °C to 32 °C. Instantaneous and cumulative fuel consumptions were measured using a fuel flow meter, and the battery energy usage was determined from the vehicle telematics during each test. The total energy consumption and total CO2 emissions were affected by the ambient temperature in all powertrain modes, including electric, hybrid electric (charge-depleting and charge-sustaining), and conventional internal combustion engine modes. The highest increase was associated with the charge-depleting hybrid electric mode, with 350% and 290% increases in energy consumption and CO2 emissions when the ambient temperature dropped from 29 °C to −24 °C. The conventional internal combustion engine mode was the least affected, with only 7% and 8% increased in energy consumption and CO2 emissions, respectively.

Effects of using nanosecond repetitively pulsed discharge and turbulent jet ignition on internal combustion engine performance

Robust ignition of hard-to-ignite fuels is essential for future spark ignited internal combustion engines, particularly for introducing efficiency-enhancing diesel-like process parameters like air excess or high amounts of exhaust gas recirculation (EGR). On the one hand, novel plasma-based ignition systems like Nanosecond Repetitively Pulsed Discharge (NRPD) are promising in extending the ignition limits and the early flame development speed. On the other hand, Turbulent Jet Ignition is effective for shortening the combustion duration and decreasing the unburned hydrocarbon emissions.This article investigates experimentally the combination of NRPD ignition and TJI. The aim is to use a technology for robust inflammation (NRPD) in combination with a technology for fast combustion of the bulk charge (TJI). For this purpose, a turbocharged light-duty four-cylinder engine operated with natural gas is used. The engine can be fitted with a classical Open Chamber (OC) spark plug or with Pre-Chambers (PC). The PCs can be filled uniquely with fuel and air coming from the Main Chamber (MC) (“passive PC”), or additional fuel can be added to the PCs (“active PC”). The air-to-fuel ratio and EGR rate can be freely controlled. Five different combustion strategies are investigated with NRPD ignition and compared against an inductive discharge ignition system. The combustion strategies are passive PC with air and EGR dilution, active PC with air dilution, and Open Chamber (OC) with air and EGR dilution. HRR evaluations and a loss analyses are performed to interpret the results.Despite the faster inflammation present with NRPD ignition, similar peak efficiencies and emissions are reached in OC configuration using the inductive discharge and NRPD ignition systems, which are achieved by varying air-to-fuel ratios (AFR) and EGR rates. Above dilution levels for peak efficiency, the efficiency using NRPD ignition decreases at a slower pace and tolerates higher AFR and EGR rates, thanks to a more complete and shorter combustion.For the PC experiments using NRPD ignition, an efficiency increases and a reduction of emissions compared to inductive discharge ignition are present for the investigated AFR and EGR rates for both active and passive PC operations. The efficiency increase is present due to a stronger pre-chamber discharge and thanks to a faster end phase of combustion. Actively fueling the PC results in faster and more complete combustion that is overcompensated by the increased wall heat losses, reducing the overall efficiency. The results show that passive PC with NRPD ignition may be an ideal ignition concept that maximizes engine efficiency and minimizes emissions.

Density-Gibbs energy correlation models for binary biofuel mixtures

The density of binary biofuel mixtures significantly influences fuel properties, directly affecting internal combustion engine performance. This research aims to develop correlational models to calculate densities in binary biofuel mixtures, leveraging the Gibbs energy mixing rule. Two correlation models are proposed: the ideal Gibbs energy mixing rule and the Gibbs energy quadratic mixing rule. These models aim to enhance the cross-interaction of Gibbs energy of activation (ΔG12) to improve predictive performance. Importantly, the constants of the existing models are directly related to thermodynamic parameters. To assess the accuracy of the models, observed densities were collected from four different binary systems: biodiesel + diesel, pure fatty acid ethyl ester + alcohol, biodiesel + alcohol, and alcohol binary mixtures, amounting to 2242 data points obtained from the literature. Based on mole fractions, both models were compared to earlier approaches. The examination revealed that the equation formulated by the quadratic mixing rule exhibited heightened precision and efficacy. Our data demonstrate that the extended ΔG12 provided the most accurate results.

Synthesis of biodiesel based on alcohol mixtures

Today, the rapid depletion of traditional fuel sources and rapid global climate change in the environment has increased interest in alternative fuels. The current situation forces many countries to implement different strategies for the development of renewable energy sources. Therefore, the environmental safety of fuels is one of the key factors in ensuring the proper operation of internal combustion engines. These strategies include the synthesis of biodiesel as renewable energy, a promising fuel for diesel engines. The goal of the work was the synthesis of biodiesel fuel from cottonseed oil using a transesterification reaction in the presence of a mixture of small molecular weight alcohols, such as methanol, ethanol, n-propanol and i-propanol, in the presence of H2SO4 as a catalyst. The reaction time was 8 hours and the mixture of alcohols was: methanol (ethanol) (34%), propanol-1 (33%) and propanol-2 (33%), yielding 80 and 83%, respectively. From the 1H NMR spectra, the participation rates of alcohols in transesterification reactions were calculated. The exploitation properties (viscosity, density, ignition temperature, etc.) of the obtained biodiesels are presented according to ASTM standards.

Investigation the performance of a new fuel produced from the phthalocyanine-gasoline mixture in an internal combustion engine

The study involved the utilization of novel developed six distinct fuel, denoted as, PG5, PG10, PG15, PG20, PG25, and PG30 and G100 (pure gasoline). These fuels were derived from various blends of gasoline and phthalocyanines. Experimental investigations were conducted to assess the internal combustion engine's performance in terms of both energy and exergy. The mixtures underwent testing across a range of engine speeds, spanning from 1400 rpm to 3000 rpm. Notably, optimal performance across all fuels and engine speeds was consistently observed at 2600 rpm. In terms of energy and exergy efficiency assessments for all fuels and engine speeds, PG25 fuel demonstrated the highest efficiency levels, with 35% energy efficiency and 33% exergy efficiency at 2600 rpm. Conversely, G100 fuel exhibited the lowest energy and exergy efficiency at the same engine speed, registering values of 27% and 24%, respectively. Meanwhile, with regard to exhaust exergy, G100 fuel demonstrated the highest exhaust energy at 10.69 kW, occurring at 3000 rpm, whereas PG25 fuel exhibited the lowest exhaust exergy, measured at 3.09 kW. It has been observed that N2 gas, one of the exhaust components that affects the exergy of exhaust gases, affects the exhaust exergy to a large extent and this ratio is approximately 50%. In addition, the sustainability index value for all fuels was found to be at most 2600 rpm. It was calculated as 1.50 for PG25 fuel and 1.32 for G100 fuel.

An Innovative Mechanical Approach to Mitigating Torque Fluctuations in IC Engines during Idle Operation

Internal combustion engines have been a major contributor to air pollution. Replacing these engines with electric propulsion systems presents significant challenges due to different countries’ needs and limitations. An active, purely mechanical solution to the problem of irregular torque production in an alternative internal combustion engine is proposed. This solution uses an actuator built on a camshaft and a spring, which stores and returns energy during the engine operating cycle, allowing torque production to be normalized, avoiding heavy flywheels. Designed for control throughout the engine’s duty cycle, this system incorporates a cam profile and a spring mechanism. The spring captures energy during the expansion stroke, which is then released to the engine during the intake and compression strokes. Simple, lightweight, and efficient, this system ensures smoother and more consistent engine operations. It presents a viable alternative to the heavy and problematic dual-mass flywheels that were introduced in the 1980s and are still in use. This innovative approach could significantly enhance the performance and reliability of alternative internal combustion engines without notable energy losses.

Constructing a Skeletal Iso-Propanol–Butanol–Ethanol (IBE)–Diesel Mechanism Using the Decoupling Method

In recent years, biofuels have gained considerable prominence in response to growing concerns about resource scarcity and environmental pollution. Previous investigations have revealed that the appropriate blending of iso-propanol–butanol–ethanol (IBE) into diesel significantly improves both the c combustion efficiency and emission performance of internal combustion engines (ICEs). However, the combustion mechanism of IBE–diesel for the numerical studies of engines has not reached maturity. In this study, a skeletal IBE–diesel multi-component mechanism, comprising 157 species and 603 reactions, was constructed using the decoupling method. It was formulated by amalgamating the reduced fuel-related sub-mechanisms derived from diesel surrogates (n-dodecane, iso-cetane, iso-octane, toluene, and decalin) and n-butanol, along with the detailed core sub-mechanisms of C1, C2, C3, CO, and H2. The constructed mechanism is capable of better matching the physical and chemical properties of actual diesel fuel. Extensive validation, including ignition delay, laminar flame speed, a premixed flame species profile, and engine experimental data, confirms the reliability of the mechanism in engine numerical studies. Subsequent investigations reveal that as the IBE blend ratio and EGR rate increase, the ignition delay exhibits an increase, while the combustion duration experiences a decrease. Blending IBE into diesel, along with a specific EGR rate, proves effective in simultaneously reducing NOx and soot emissions.

Techno-economic assessment of hydrogen as a fuel for internal combustion engines and proton exchange membrane fuel cells on long haul applications

Powertrain energy conversion and management are critical factors in providing affordable and robust solutions for transport decarbonization. Various powertrain technologies are being proposed to reduce the impacts of transportation-related carbon dioxide emissions, such as battery electric, fuel cell, and conventional vehicles running with lower carbon fuels. Specifically for the commercial sector, hydrogen internal combustion engines and fuel cells are being extensively discussed. In this sense, this investigation evaluates the benefits and areas of enhancement for hydrogen internal combustion engines and fuel cells from a techno-economic perspective. Power plant models were developed and validated in GT-Power, and detailed investigations on the energy loss pathways were performed. In addition, the powertrains are included in full longitudinal vehicle models and submitted to different driving cycles, representing homologation and real-world driving conditions, with the intent to understand the effect of the cycles from a global energy management perspective. Finally, the fuel consumption results are used as inputs for a total cost of ownership calculation to determine the economic viability of each powertrain. Overall, fuel cells offered efficient operation across the conditions assessed, with engine-powered powertrains showing reduced efficiencies ranging from 23 % to 63 % depending on the cycle and payload. The limited peak efficiency for the spark-ignited low-pressure hydrogen direct injection engine was a dominant factor for the reduced performance of this platform. Strategies for efficiency improvement are identified that could lead to improved internal combustion engine operation. Despite the limited efficiency benefits of hydrogen internal combustion engines, total cost of ownership calculations show hydrogen internal combustion engines being the most cost-effective solution in the near to medium-term scenario.

Stress mitigation of a thermal engine head block using the bioinspired BGM-FEM method

Structural optimization plays a pivotal role in the design and development of engine heads, as it directly affects the performance, efficiency, and durability of internal combustion engines. In this paper, we propose a novel approach for the thermo-structural optimization of the internal surfaces of the engine heads, using the Biological Growth Method (BGM). The BGM is a bio-inspired technique that mimics the growth patterns observed in some biological organisms, able to achieve superior structural efficiency thus generating optimal designs. The effectiveness of the BGM methodology, coupled with mesh morphing techniques based on Radial Basis Functions (RBF), is in this work demonstrated for several districts, effectively reducing material usage and enhancing structural performance.