Browse Topic: On-board energy sources

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Alcohol-Based Energy Carriers in Transportation: Status, Standards, and Outlook2026-37-0042To be published on 06/09/2026
The global transport sector accounts for approximately 28% of total energy consumption and 15.8% of greenhouse gas emissions worldwide, with road transport alone responsible for 11.8%. As the world seeks pathways toward carbon neutrality, methanol and ethanol emerge as promising alternative energy carriers capable of leveraging existing logistics infrastructure while reducing dependence on fossil fuels. This review examines the production pathways, lifecycle considerations, and costs associated with both alcohols. Global methanol production reached 111 million metric tons in 2022, and global ethanol production totaled approximately 93.3 million metric tons in 2024. In comparison, the yearly production of gasoline and diesel amounts to over 2 billion metric tons per year. The review evaluates fuel requirements across multiple transport modes, including passenger vehicles, light- and heavy-duty vehicles, maritime shipping, aviation, and rail, and assesses regulatory frameworks governing
Fitz, Patrick, Fellner, Felix, Rößlhuemer, Raphael, Härtl, Martin, Jaensch, Malte
On natural gas combustion split into diesel like architecture of a compression ignition engine retrofitted for spark ignition operation2026-37-0029To be published on 06/09/2026
In commercial areas that no longer favor diesel engine, such as Europe, it might be interesting to convert an existing compression ignition (CI) engine to the spark ignition (SI) operation and to use natural gas (NG) because of its advantages: availability of still abundant NG supplies worldwide and environmental benefits of NG compared to conventional liquid fossil fuels. This paper presents experimental results on NG combustion inside such a converted engine with diesel-like architecture dedicated to light-duty vehicles (LDV) and passenger cars (PC). Particularly, our study carried out at the engine test bed revealed that in certain operating points (low speed and load, stoichiometric mixture and rather high spark advance), the combustion is split into two distinct events, which is not specific to the standard SI engine. This is clearly illustrated by a rate of heat release (RoHR) profile with two peaks. This kind of RoHR profile appeared following a spark advance sweep carried out
Clenci, Adrian F., Popa, Robert, Berquez, Julien, Iorga-Siman, Victor, Magheru, Catalin, Punov, Plamen, Niculescu, Rodica
Development of a Diesel Combustion System for Next‑Generation Heavy‑Duty Engines Using a Synergistic Analysis‑and‑Testing Approach2026-37-0004To be published on 06/09/2026
Regulators and policymakers have introduced increasingly stringent limits on tailpipe CO₂ and pollutant emissions to accelerate the decarbonization of heavy-duty vehicle applications. The development of innovative propulsion technologies — such as advanced combustion systems, low-friction reciprocating components, and improved aftertreatment solutions — combined with hybridization and the adoption of alternative fuels (e.g., biogas, HVO, green hydrogen), represents a key pathway for meeting future emission and GHG targets. In this study, advanced combustion systems were developed for a 13‑liter diesel engine for heavy-duty truck applications, with the objective of complying with forthcoming Euro VII regulations while maximizing thermal efficiency. The combustion system architecture—including open-bowl geometry with high aspect ratio, injector nozzle with wider spray opening angle, and reduced swirl ratio—was optimized using a Machine Learning–algorithm trained on high-fidelity 3D CFD
Belgiorno, Giacomo, Centini, Maria Pia, Pezza, Vincenzo, Cozza, Ivan F., Pesce, Francesco C., Vassallo, Alberto, Colombo, Giovanni, Gallo, Alessandro, Mirzaeian, Mohsen, Borg, Jonathan
Impact of Compression Ratio and Stroke on Hydrogen Requirement for Emission Optimized Operation of an Ammonia-Fuelled Spark-Ignition Engine2026-37-0030To be published on 06/09/2026
Ammonia-fuelled engines have emerged as a promising route toward net-zero emission targets due to ammonia’s carbon-free nature, ease of storage, and established handling infrastructure. However, the low burning speed and narrow flammability limits of ammonia pose a significant combustion challenge, which can be addressed through hydrogen co-fuelling. For practical implementation, on-board hydrogen production via thermal catalytic cracking of ammonia is an attractive solution, as it eliminates the need for external hydrogen storage and associated handling and capital costs. Previous studies by the present authors identified a lean operating strategy that achieves an equal molar ratio of NOx and unburned ammonia (NH3), enabling complete conversion to nitrogen and water vapour when coupled with a Selective Catalytic Reduction (SCR) system. This strategy was further validated using cracked ammonia-derived hydrogen in place of bottled H2 through an on-board cracker, thereby representing a
Yadav, Neeraj Kumar, Ambalakatte, Ajith, Geng, Sikai, Gopakumar Suja, Gagan, Birch, Alexander, Cairns, Alasdair, Harrington, Anthony, Hall, Jonathan
Methane Emission Mitigation in Large-Bore Dual-Fuel Engines via Negative Valve Overlap Diesel Injection: Thermochemical Pathways and Reactivity Control2026-37-0045To be published on 06/09/2026
Low-load natural gas–diesel reactivity controlled compression ignition (RCCI) in medium-speed marine engines is constrained by an insufficient charge thermal state. This limitation leads to partial fuel oxidation, producing high methane emissions. This work evaluates the use of negative valve overlap (NVO) combined with NVO diesel injection as an in-cylinder reactivity enhancement strategy. The simulation study was performed using the University of Vaasa's advanced thermo-kinetic multi-zone model (UVATZ), extended for reactive simulations during NVO. The extended framework was validated against test-bench data from a prototype Wärtsilä 6L20 dual-fuel engine operating in RCCI mode. The baseline low‑load operating point for reforming simulations was defined by reducing the intake manifold temperature to replicate conditions close to partial misfire with 52% combustion efficiency. The parametric sweeps of NVO injection timing and ratio showed that the strategy can be used for in-cycle
Soleimani, Amir, Nurmi, Mikael, Hunicz, Jacek, Kim, Jeyoung, Hyvonen, Jari, Mikulski, Maciej
Performance and Combustion Characteristics of Coryton SUSTAIN Classic Super 80 Carbon-Neutral Fuel Versus E95 in a 1980s Fiat 500 Engine2026-37-0033To be published on 06/09/2026
The energy transition requires a rapid reduction in the use of fossil fuels, whose combustion generates substantial greenhouse-gas emissions. In Europe, transport alone accounts for roughly a quarter of total greenhouse-gas emissions, with road transport being the predominant component. In this context, the use of biofuels has emerged as a potential solution for limiting further increases in CO₂ emissions. However, most studies available in the literature evaluate the performance of these fuels on modern engines, while their effects on historic carburetted engines remain largely unexplored. This is particularly significant given the large fleet of historic vehicles across Europe, supported by a long-standing tradition of vehicle preservation, associations, and classic car collectors. The main historic-vehicle federations advise caution and the use of low-ethanol formulations so as not to damage elastomers, fuel tanks, and carburettor float bowls. For this reason, a few suppliers have
Tarchiani, Marco, Fossati, Federico, Raspanti, Sandro, Baroni, Alberto, Ferrara, Giovanni, Romani, Luca
Development of a 0D – 1D numerical model for the thermal management of a heavy – duty PEMFC2026-37-0006To be published on 06/09/2026
The rising concerns on climate change are leading to a substantial increase in the efforts to detach from fossil fuel-based technologies towards more sustainable sources. In this context, Fuel Cell (FC) technology in gaining an increasing range of practical applications, offering both advantages and technical challenges. Despite the theoretical efficiency, these systems suffer a significant loss of performance under high loads, resulting in a relevant heat generation. To this end, considered a 200-kW low temperature Proton Exchange Membrane Fuel Cell (PEMFC), a 0D – 1D model of the cooling system is developed in GT – SUITE environment and the results discussed in this paper. In detail, the model is used to investigate the influence of design parameters on the effective efficiency of the system to dissipate the excessive heat produced by the FC. Additionally, a second model (STACK-ONLY) comprehensive of the Membrane Electrode Assembly (MEA) subcomponents properties was built to verify
Cecere, Giovanni, Antetomaso, Christian, Irimescu, Adrian, Merola, Simona
Hybridized Diesel Powertrains - an important enabler for commercial applications on the long journey towards full electrification2026-37-0022To be published on 06/09/2026
The ongoing efforts for reduction of the traffic-related greenhouse gas emissions and, at the same time, the mitigation of harmful pollutant emissions from vehicle exhaust emissions are important development tasks for the entire automotive industry worldwide according to demand to provide clean and efficient products. Further tightened fleet average FE standards and ultra-low limits for exhaust emissions require the continuous development of new propulsion system types. Due to the given reluctance of the end customer and corresponding low acceptance of fully electrified vehicles, especially in the commercial vehicle segment, new and innovative topologies are needed to meet regulatory requirements and maintain the high versatility of today’s dominating solutions. For further optimisation of operating conditions with enhanced fuel efficiency, the technical strategy is also determined by uplifting the attractiveness of electric driving incl. the avoidance of areas with poor ICE efficiency
Koerfer, Thomas
Comparative Toxicological Assessment of Exhaust Emissions from Modern Low-Emission Passenger Vehicles2026-37-0005To be published on 06/09/2026
The transition towards low-emission vehicle technologies, driven largely by efforts to reduce fleet-average CO2 emissions, has led to the widespread introduction of advanced powertrains, including hybridized gasoline vehicles, modern diesel vehicles, and compressed natural gas (CNG) vehicles [1]. While these technologies are primarily promoted for their reduced regulated emissions, their comparative toxicological impacts under realistic driving conditions remain insufficiently understood. This study presents a comparative toxicological assessment of exhaust emissions from five state-of-the-art passenger vehicles representing different propulsion technologies. The vehicles were tested on a chassis dynamometer under controlled laboratory conditions, following a common experimental protocol. The test matrix included gasoline vehicles with varying degrees of hybridization and particulate filtration (with and without gasoline particulate filters, GPF), a diesel vehicle equipped with a
Tsakonas, Georgios, Stamatiou, Rodopi, Lazou, Antigone, Samaras, Zissis, Elihn, Karine
Numerical simulation of spark-ignited flame kernels towards prospective application to hydrogen SI engines2026-37-0015To be published on 06/09/2026
The ongoing energy transition demands the decarbonization of the transport sector, for which the use of premixed hydrogen in spark-ignition (SI) engines appears very promising. However, modeling the combustion of the lean hydrogen/air mixtures required for safe, efficient, and low-NOx engine operation involves multiple open issues. Correct prediction of flame kernel initiation and growth is a difficulty that hydrogen shares with hydrocarbon fuels, while properly accounting for the instabilities that characterize lean hydrogen flames is an additional demanding task. In this work, a 1D kernel expansion model of general validity recently proposed by the authors is implemented into OpenFOAM, an open-source 3D CFD software package, to enable numerical simulation of expanding spark-ignited flame kernels. Firstly, the OpenFOAM framework is presented focusing on XiFluid, its thermophysical combustion model based on a regress variable whose evolution depends on the laminar flame speed. Then
Dotteschini, Enrico, Pretto, Marco, Giannattasio, Pietro, Gadalla, Mahmoud
Evaluation of Flamelet-Based Combustion Models for Hydrogen-Ammonia Spark-Ignition Engines2026-37-0027To be published on 06/09/2026
Besides the electrification of the transport sector, the growing interest in alternative fuels for internal combustion engines represents a promising pathway to effectively decarbonize transportation over the coming decades. Predictive combustion models implemented within CFD frameworks are a critical tool to guide the design of next-generation internal combustion engines fuelled with alternative fuels. Accurate prediction of the combustion heat release process is influenced by multiple interacting parameters, requiring combustion models that can reliably adapt to variations in fuel chemical properties and operating conditions. In this study, two well-established combustion models considered to model combustion development in Spark-Ignition engine, namely the Extended Coherent Flame Model (ECFM) and the G-equation model, are compared to assess their capability to adapt to changes in fuel chemical composition. Both models, based on the flamelet formulation are deliberately tested beyond
Sola, Riccardo, Baratta, Mirko, Misul, Daniela, Rousselle, Christine, BREQUIGNY, Pierre, Colin, Olivier
Development and Experimental Validation of a 1D Model for Performance and Emissions Analysis of Oxygenated Fuel Blends in a CI Engine2026-37-0028To be published on 06/09/2026
Emissions reduction remains a major concern for internal combustion engines in view of increasingly stringent environmental regulations. To address these challenges while maintaining acceptable engine performance, a wide range of alternative fuels and fuel blends have been investigated to ensure the continued viability of CI engines. This study reports the effects of blending the oxygenated fuel diethylene glycol diethyl ether (DGDE) with hydrotreated vegetable oil biodiesel (HVO) on engine performance and emissions. The investigation is conducted on a 2.3-liter, four-cylinder, common-rail diesel engine equipped with variable geometry turbocharger and a high-pressure exhaust gas recirculation system. The objectives of this study are achieved by developing a one-dimensional predictive engine model using the commercial GT-Suite software. The engine model is developed and experimentally validated, at different operating conditions and HVO–DGDE fuel blends, to predict their effects on
Arain, M Wajahat Rasool, Foglia, Antonio, Frasci, Emmanuele, Vitek, Oldrich, Pianese, Cesare, Arsie, Ivan
An Along-the-Channel Pseudo-2D Approach for Spatially Resolved PEM Fuel Cell Dynamics2026-37-0010To be published on 06/09/2026
The longevity of proton-exchange membrane fuel cells is influenced by degradation processes whose rates depend on local operating conditions such as temperature, humidity, liquid-water saturation, and reactant availability. Along-the-channel gradients imposed by the flow field can therefore be relevant when interpreting operating behaviour and when formulating models intended to support control and system studies. The AlphaPEM framework provides a dynamic through-plane description, but, in its baseline form, does not explicitly resolve axial non-uniformities in the MEA. This paper presents a pseudo-2D extension of AlphaPEM that couples an along-the-channel gas-channel model to a segment-wise MEA submodel. The original model already implements a plug-flow model discretized into multiple axial control volumes to capture the evolution of species and water vapour along the flow direction. This contribution adds a MEA model derived from the original through-plane formulation with local
Ringeisen, Björn, Günthner, Michael, Kargl, Pascal
Nitrogen-based emissions from Ammonia Combustion in a Heavy-Duty Spark Ignition Engine2026-37-0032To be published on 06/09/2026
Ammonia (NH3) is increasingly recognized as one of the paths toward decarbonizing power generation and transportation. Its carbon-free molecular structure and ease of storage compared to hydrogen put NH3 at the forefront of alternative fuels. However, transitioning from hydrocarbon fuels to NH3 in internal combustion engines significantly alters the profiles of nitrogen oxide (NOx) and nitrous oxide (N2O) emissions. In traditional hydrocarbon combustion, NOx is formed mainly via the thermal Zeldovich mechanism, where atmospheric nitrogen reacts with oxygen at high temperatures. In contrast, ammonia combustion introduces "fuel-NOx," where the nitrogen atom within the NH3 molecule itself is oxidized. This study used experiments and numerical simulations to evaluate the effect of engine geometry and operating condition on these differences. In addition, the study observed the differences in NOx and N2O formation and destruction with respect to the engine cycle timeline. While ammonia's
Trujillo Grisales, Juan, Saenz Prado, Stefany, Alvarez, Luis F., Akkerman, Vyacheslav, Dumitrescu, Cosmin E.
Experimental investigation on cold start and warm-up phases for an ethanol fueled SI engine.2026-37-0031To be published on 06/09/2026
Engine operation during the initial warm-up period is characterized by pronounced thermal non-uniformities, which have a direct impact on fuel efficiency, combustion stability, tailpipe emissions and engine long-term reliability. For these reasons, accelerating the warm-up process represents an effective strategy to improve both environmental impact and overall engine performance. This paper presents an experimental study carried out on a 1.2 liter, naturally aspiered, four-cylinder SI engine equipped with a Port Fuel Injection (PFI) system. The engine is fueled with standard gasoline and an ethanol-gasoline blend containing 30% ethanol by volume (E30), with the aim of assessing the influence of fuel formulation on thermal evolution after a cold start. Each test begins with the engine at ambient temperature and is continued until thermal equilibrium is established. Experiments are carried out at a single steady operating point of 2000 rpm and 20 Nm, selected to reproduce representative
Falbo, Luigi, Falbo, Biagio, Perrone, Diego, Castiglione, Teresa
Potential of ORC-Based Waste Heat Recovery in Conventional and Hybrid Heavy-Duty Powertrains2026-37-0018To be published on 06/09/2026
Heavy-duty vehicles are major contributors to greenhouse gas emissions and urban air pollution, particularly under cold-start and transient operating conditions where engine efficiency and exhaust aftertreatment effectiveness are reduced. In this context, waste heat recovery (WHR) technologies represent a practical pathway for improving fuel efficiency and reducing CO₂ emissions in real-world heavy-duty applications. This study investigates the integration of an Organic Rankine Cycle (ORC)–based WHR system within conventional and hybrid electric powertrain architectures applied to a reference heavy-duty truck (ISUZU FTR850). A sensitivity analysis is performed on four WHR configurations, combining shell-and-tube and plate heat exchangers with simple and regenerative ORC layouts. For the parallel hybrid configuration, two engine sizes and two energy management strategies are compared: a fuel-minimizing fuzzy logic rule-based strategy and a constant-power strategy aimed at stabilizing
Donateo, Teresa, Morrone, Pietropaolo
Development and validation of a one-dimensional model for an opposed-piston free-piston engine generator with parametric analysis2026-37-0021To be published on 06/09/2026
Opposed-piston free-piston engine generators (OFPEGs) have emerged as a promising technology for next-generation hybridized and electrified transportation systems, offering the potential for high efficiency, reduced mechanical complexity, and favorable noise, vibration, and harshness (NVH) characteristics. By eliminating the conventional crankshaft mechanism and directly coupling a free-piston engine with linear generators, OFPEGs enable the direct conversion of combustion energy into electrical power. This architecture is particularly attractive for hybrid and range-extender applications, where operational flexibility and high system efficiency are critical to achieving significant reductions in fuel consumption and CO₂ emissions. Despite these advantages, the performance of OFPEG systems is governed by a strong coupling between piston dynamics, in-cylinder combustion processes, and electrical loading conditions. This coupling presents substantial challenges for system design, control
Wang, Jiayu, Morandi, Nicola, Lucchini, Tommaso, FENG, HUIHUA, Jia, Boru, Ren, Peirong
Comparison of Detailed Chemistry and Flamelet-Based Models for Hydrogen Combustion in a Heavy-Duty PFI Engine2026-37-0014To be published on 06/09/2026
Addressing climate change requires substantial reductions in emissions from the transportation sector, where alternative fuels for internal combustion engines play a crucial role. Among these options, hydrogen stands out as a compelling energy carrier capable of enabling low-carbon combustion while leveraging existing engine technologies. Its adoption can support a transition toward fuel-flexible powertrains and deliver rapid decreases in exhaust carbon emissions. This approach is particularly relevant for hard-to-abate segments such as heavy-duty transportation, where full electrification remains challenging. Building on this perspective, this numerical study investigates the modelling behaviour of a heavy-duty port fuel injection (PFI) internal combustion engine fuelled with hydrogen. Initially, the mixture was assumed to be fully premixed to avoid uncertainties related to injection and mixing processes and to significantly reduce computational cost; this assumption was subsequently
Scopelliti, Alex, Misul, Daniela Anna, Baratta, Mirko, Gallo, Alessandro, Rapetto, Nicola, Vargiu, Luca
Quantum-Inspired Evolutionary Optimization for Optimal Re-Orbital Entry Trajectory Planning in Support of In-Orbit Satellite Refueling Missions2026-26-0725To be published on 06/01/2026
Trajectory optimization for reusable launch vehicles is a critical challenge in space mission design, aiming to determine fuel-efficient paths for spacecraft during ascent, hover, and descent phases. Minimizing fuel consumption not only enhances cost-effectiveness but also improves mission sustainability. The optimization process is governed by nonlinear orbital mechanics, gravitational perturbations, atmospheric drag, and operational constraints such as thrust limits and collision avoidance. These factors make the problem highly nonconvex and discontinuous, posing significant difficulties for classical gradient-based approaches, which often fail to identify global optima. In this work, we formulate the trajectory optimization problem for a reusable rocket executing an ascent–hover–descent cycle. The vehicle must ascend to a specified target altitude, maintain a stable hover for a given duration, and then return to the launch site. The primary decision variable is the throttle control
Eswara Sai Kumar, Kandula, Singh, Utkarsh, Pohankar, Pritam, A, Anoop, Maharana, Priyabrata, Lineswala, Rut
Data-Driven Air Traffic Management: Forecasting Demand, Modeling Delay Propagation, and Demand Capacity Balancing2026-26-0772To be published on 06/01/2026
Air traffic management (ATM) systems must accurately estimate flight demand, analyze network delays, and optimize capacity. This research uses a global airline dataset with passenger information, airport characteristics (including geographic markers and continental classifications), flight scheduling data (timing and destination details), crew information, operational status records, and OpenSky Network real-time states data to create an intelligent ATM decision-support framework. Advanced machine learning (ML) methods like gradient boosting and sequential modeling are used to build network models of flight routes between origins and destinations, develop temporal demand patterns for individual airports, analyze delay factors, and predict congestion periods. The research uses mixed-effects statistical models using crew data to measure operational variability and demographic and nationality-based analysis to identify demand trends for improving staffing and security processing during
Senthilkumar, N., S, Gopalakrishnan, Gopinath, S
Weight Estimation of Novel Aircraft Configurations in Early Design Phase2026-26-0773To be published on 06/01/2026
Initial Weight estimation based on the Top Level Aircraft Requirements, hereon referred to as TLAR, is one of the key points to begin with the design of any aircraft. A quick and accurate estimation at the initial stages allows to achieve optimal design solution in fewer steps. This has more relevance in a setup like DOE, i.e., Design of Experiments, where the idea is to explore the complete design space and choose the best solution. At present, there are techniques available to estimate the weight from TLAR for conventional tube and wing configurations with JetA1 fuel. These techniques are primarily based on trends and empirical equations that have been derived from historical data of aircrafts previously built. A lot of new aircraft concepts have been (eg: VTOL) and are being (eg - BWB, H2 as fuel, OpenFan Propulsion etc.) considered for the commercial future. Currently, there are no standard methods established to estimate their weights due to the scarcity of historical data. The
Goyal, Tushar
Conceptual Design of Hydrogen Fuel-Cell-Based Utility Aircraft2026-26-0783To be published on 06/01/2026
The aviation industry contributes to around 2% of global carbon dioxide emissions. As various sectors of the economy look to reduce their global carbon footprint, the aviation industry is positively acknowledging alternatives to jet fuel. Hydrogen proves to be one such alternative having a high energy density and producing zero carbon emissions on combustion. Hydrogen when used in a jet engine produces water vapour and NOx emissions. In order to reduce the effect of GHGs, the current study aims to develop aircraft concepts suitable with hydrogen propulsion through fuel cells for a short-haul commercial mission profile. Aircrafts such as Metro-23 and Dornier 228-212 were referenced for the requirements of a utility turboprop aircraft. The weight estimation was done to obtain the take off weight of 10,863 kg following the optimization of thrust to weight ratio and wing loading to calculate the initial dimensions. OpenVSP was used to model the initial structure of the aircraft. For the
Bhattacharya, Anisha, Seetha Ramu, Sree Valli, C N, Lakshmi Manasa, Rohit, Benjamin
Thermal Management System in Commercial Aircraft: A Case Study on Passenger Egress System2026-26-0760To be published on 06/01/2026
It is known fact that Thermal management systems are essential to the safety, operational efficiency, and structural integrity of present-day commercial aircraft. Very critical insulation and thermal protection materials are utilized across various aircraft zones to mitigate extreme temperature challenges, ranging from cryogenic conditions at high altitude to pyrotechnic conditions at low altitude/ sea level. Some of the examples where specific materials at their functional role are, • In engine pylons and nacelles, high temperature alloys such as Titanium and Inconel, along with ceramic Matrix composites (CMCs) serve as firewalls and heat shields, which are designed to contain fires and protect primary structures. • In bleed air ducting, fiberglass or silica insulations blankets are employed to prevent thermal degradation of surrounding aluminum and composite components, when air at temperatures above 200 degree C flows. This paper focuses on the critical insulation and thermal
Govindaraju, Parthasarathy, Nanjundegowda, Harshavardhana
A Comparative Assessment of Fuel Cell and Battery Powertrains for Formula Student Electric Applications2026-01-5032To be published on 04/27/2026
The organizers of the most prominent Formula Student competitions have recently initiated a preliminary feasibility study on the application of hydrogen-based propulsion technologies in future single-seater race vehicles. These include electric powertrains with electrochemically converted hydrogen in fuel cell–powered vehicles, competing within the electric championship league. Based on the initial set of regulations, this study presents a model-based comparison between battery-powered (BEVs) and fuel cell–powered electric vehicles (FCVs) for Formula Student. The analysis is conducted using energy, power, and efficiency metrics from four candidate models of propulsion systems, implemented in an open and publicly available MATLAB script: two BEVs with varying battery capacities, and two FCVs employing different hybridization strategies. The aim of this study is to pinpoint and quantify the advantages and disadvantages of each technology for the Formula Student use case, and to identify
Martoccia, Lorenzo, Breda, Sebastiano, Fontanesi, Stefano, d’Adamo, Alessandro
Experimental Study of Knock Resistance Offered by Direct Water Injections in a Single-Cylinder Spark Ignition Engine03-19-02-00114/11/2026
Stochastic end-gas autoignition in spark ignition (SI) engines, commonly called “knock,” limits attainable engine efficiencies. Multiple pathways to extend SI engine operation into knock-limited regions have been studied, including direct water injection (DWI). This study employs single-cylinder engine experiments with a centrally mounted water injector to investigate the knock resistance offered by compression stroke water injections, which, through incomplete mixing, can thermally stratify the cylinder. In SI, thermally stratifying injections are expected to forcibly widen the cylinder temperature distribution by preferentially cooling the cylinder periphery. The end-gas is in the cylinder periphery. A cooler end-gas would result in longer ignition delays, thus providing knock resistance. The difference between intake temperature required to match knock-limited CA50 and a baseline intake temperature at the load of 8 bar IMEPg (gross indicated mean effective pressure) was used to
Datar, Aditya, Vedpathak, Kunal, Gainey, Brian, Lawler , Benjamin
Novel Air System for 300 kW Heavy Duty Fuel Cell2026-01-04344/7/2026
Hydrogen fuel cell powered vehicles for heavy duty trucking are a promising path for reducing future vehicle emissions due to their reduced mass for storage and faster refueling compared to battery electric trucks. These benefits come at the cost of increased system complexity stemming from the fact that fuel cells generate electricity through a chemical reaction which must be tightly controlled. The air handling system delivers the proper amount of air (oxygen) to react with fuel (hydrogen) in the fuel cell to produce power. Air delivery requires significant power and is the largest parasitic loss for a 300 kW fuel cell. Today’s systems use an electric motor driving an air compressor to supply pressurized air to the fuel cell stack. By operating at elevated pressure levels, fuel cells can achieve higher power density, which is important for vehicle powertrains. In addition to parasitic power loss, hydrogen fuel cell systems often have reliability issues associated with the air
Reich, Evan, Swartzlander, Matthew, Wine, Jonathan, McCarthy, Jr., James, Miller, Eric, Akhtar, Saad, Reddy, Sharan, Lawy, TJ
Effect of Liquidized-Gas Fluid Properties in a High-Pressure Fuel Pump2026-01-02734/7/2026
Paper considers the effects of fluid properties from liquified gases during high pressure pumping, at ranges from 200 to 1500 bar, and at speeds of 500 to 1500 rpm. Tests represent highest to date pressure ranges attained with liquified fluids such as DME. The paper examines the effects of compressibility on the pumping and resulting loading torque characteristics described over the pumping cycle as resolved by a high-fidelity sensor. Experimental tests and simulated performance based on a 1-D model are compared for Diesel and DME for a high-pressure fuel pump, piston style, featuring two plunger-barrels. Each of the pump’s plunger-barrel is inlet metered electronically, allowing the pump to run at a variable displacement and with the flexibility to deactivate one or both plungers fully. The model captures the response of the inlet metering valve and output valve lifts across speed and loads. The output check valve is subject to pressure pulsations and shows the importance to optimize
de Ojeda, William, Wu, Simon (Haibao)
Model-Based Development of the “Big 5” in Fuel Cell Systems2026-01-00724/7/2026
Fuel cell systems are gaining traction across heavy-duty applications, driven by global decarbonization targets. Managing their inherent complexity and diverse architectural requirements, commonly organized into the “Big 5” fuel cell subsystems (stack, thermal, electric, anode, and cathode), necessitates advanced Model-Based Development (MBD) approaches. This paper presents and validates a constraint-graph-based, equation-oriented, acausal MBD methodology for fuel cell system (FCS) development, implemented in an industrial modeling environment. This methodology supports scalable functional and software development from 75 kW single-stack systems to twin-stack configurations exceeding 250 kW. It facilitates robust parameterization and reuse of consistently formulated, subsystem-level physical models across Model-in-the-Loop (MiL) to Hardware-in-the-Loop (HiL) environments, ensuring numerically robust software architectures and improved embedded control quality. Industrial application
Bandi, Rajendra Prasad, Bleile, Thomas
Energy Efficiency Analysis of U-Haul Truck and Trailer Systems: Impact of Tongue Weight and Load Variations2026-01-04664/7/2026
The demand for improved energy efficiency in real-world vehicle operations continues to grow with technology enhancement. When transporting large cargo loads with passenger pickup trucks and rental trailers, the interaction between vehicle payload, towing configuration, and fuel consumption becomes a key factor in overall system efficiency. Understanding how towing configurations and trailer loading influence fuel consumption and vehicle performance is critical for both consumer guidance and vehicle system design. This study investigates the energy efficiency of U-Haul truck and trailer systems, with a particular focus on the influence of trailer tongue weight. U-Haul truck and trailer simulation models were developed using AVL Vehicle Simulation Model (VSM) software, with an F-350 engine brake-specific fuel consumption (BSFC) map integrated to represent realistic engine performance. Two configurations with equal payload were evaluated: (1) a U-Haul truck alone, and (2) a U-Haul truck
Wang, Gang, Kathadi, Mohammad, Yang, William, Chen, Yan
Effect of Passive Pre-Chamber Geometry on Performance and Emissions of a Single-Cylinder Natural Gas Large Bore Engine2026-01-03334/7/2026
The maritime industry is one of the most energy-intensive sectors, characterized by high fuel consumption and significant environmental impact. As global trade relies on shipping, the challenge of reducing pollutants and greenhouse gas emissions becomes ever more pressing. Natural gas (NG) is considered as a transitional fuel, capable of lowering CO₂ emissions by 20–30% compared to conventional marine fuels. However, to fully harness this potential, significant advances in combustion technology are necessary, particularly with ultra-lean combustion strategies. One of the most promising pathways is pre-chamber combustion, a solution that can simultaneously improve the efficiency and sustainability of NG marine engines. In this scenario, the passive pre-chamber geometry plays a key role, as it directly influences ignition behavior, combustion stability, and exhaust emissions. This work presents an experimental study conducted on a single-cylinder marine engine prototype, retrofitted from
Marchitto, Luca, Tornatore, Cinzia, Pennino, Vincenzo, Mariani PhD, Antonio, Beatrice, Carlo, Accurso, Francesco, Gorietti, Valentina, Pesce, Francesco, Giardino, Angelo, Vitti, Luciano
Impact of Hydrogen on Methane and Pollutant Emissions over Three-Way Catalysts with Natural Gas–Hydrogen Blends2026-01-03574/7/2026
Blending natural gas (NG) with hydrogen (H₂) can improve combustion and engine performance while potentially facilitating the catalytic conversion of methane and other pollutants, resulting in cleaner tailpipe emissions. This study evaluates the impact of H2 on the conversion of methane, CO, and NOx emissions on a commercial three-way catalyst (TWC) in a flow reactor using synthetic gas mixtures that simulate stoichiometric engine exhausts with NG or NG+H₂ combustion. The work examines whether, and how, the additional amount of H₂ in the exhaust stream affects the conversion efficiency of methane and other pollutants. Experiments were conducted with both degreened and aged catalysts under controlled conditions, systematically varying temperature, the air-to-fuel equivalence ratio (λ), and λ modulation. Test conditions covered λ values from 0.996 to 1.000 to represent nominally stoichiometric engine operation with different λ modulation amplitudes, as well as a range of temperatures to
Prikhodko, Vitaly, Wang, Min, Park, Yeonshil, Chen, Hai-Ying, Pihl, Josh
Modelling of Cold Start Processes in Proton Exchange Membrane Fuel Cells2026-01-04964/7/2026
In this work, a numerical study is carried out to analyze the cold start process of a three-dimensional proton exchange membrane fuel cell (PEMFC) with a three-parallel serpentine flow channel design. The investigation is mainly focused on developing a transient ice formation model in a computational fluid dynamics (CFD) environment to predict ice formation during subfreezing startup and to analyze its influence on the operation of the fuel cell. The model considers sublimation and de-sublimation processes inside the gas diffusion layer and the catalyst layer. To account for the influence of ice on electrochemical reactions, the local transfer current is reduced depending on the fraction of ice volume present in the porous regions. The proposed model is validated against experimental data, and the comparison shows that the model can successfully reproduce both the successful and the failed cold start cases under different initial temperatures. The study identifies two main factors
ma, Shihu, Champhekar, Omkar, Han, Chao
Effect of Renewable Fuel Blends on Particulate Emissions under Medium Engine Load and Injector Coking Conditions in a GDI Engine2026-01-03014/7/2026
Renewable gasoline is blended with fossil gasoline as part of the effort to achieve zero net carbon emissions. This study examined how five gasoline fuels with different hydrocarbon compositions affect engine-out gaseous and particle number (PN) emissions. Gasolines F3 and F4 reduce GHG emissions by 54% and 35%, compared with fossil gasoline. The other three gasolines reduce GHG emissions by 4-9%. Tests were conducted on a single-cylinder GDI engine at 10-14 bar indicated mean effective pressure (IMEP) and 2000 rpm. The injector-tip coking behavior of the test fuels and the resulting PN emissions were also investigated at 10 bar IMEP. Spray plume targets and start-of-injection (SOI) timing were adjusted to examine how the test fuels affected PN emissions. An endoscope was used to identify the sources of soot during fuel combustion. The experimental results show that PN varies with gasoline composition and engine operating conditions. Aromatics and olefins contribute more to injector
Muniappan, Krishnamoorthi, Dahlander, Petter, Helmantel, Ayolt, Alemahdi, Nika, Lehto, Kalle
Achieving 70% Urban Fuel Consumption Reduction: An Opposed-Piston Engine-Based Mild-Hybrid Powertrain Architecture for Light Commercial Vehicles (JLA-2/JLA-T)2026-01-04324/7/2026
This paper proposes a novel powertrain architecture for the urban Light Commercial Vehicle (LCV) segment, leveraging the compact JLA-2 opposed-piston (OP) engine paired with the reconfigurable JLA-T mild-hybrid architecture. Within SAE literature, OP engines are consistently associated with simplicity. As highlighted by Tom Ryan III (2008 SAE President) in the foreword of Opposed Piston Engines: Evolution, Use, and Future Applications, this architecture is characterized by its manufacturing simplicity” and described as a “relatively simple, robust, and cost effective” power unit solution. The present work builds on this established view. The JLA-2 engine solves traditional packaging constraints by reducing the block width by 30% for horizontal installation and is volumetrically self-sufficient, eliminating external compressors. Although the gear train required for crank synchronization introduces design challenges, explicitly accounted for in our model, the elimination of the cylinder
Nigro, Norberto, Aguerre, Horacio, Carignano, Mauro Guido, Alonso, José Luis, Juni, Carlos A.
The Influence of Split Injection Ratio on Efficiency and NO x Emissions in a Pilot Diesel-Ignited Hydrogen Direct Injection Engine2026-01-03294/7/2026
This study investigates the impact of the hydrogen split injection ratio on the combustion of pilot diesel-ignited hydrogen direct-injection engines, which is expected to affect hydrogen-air mixture conditions and thus flame propagation and diffusion flame developments. Experiments were conducted on a 1-litre single-cylinder diesel engine equipped with an additional hydrogen injector operating at 35 MPa. Hydrogen accounting for 95% of total input energy was injected at 150 and 60 °CA bTDC for the first and second pulses, which were selected as high-efficiency injection timings from previous equal-split injection tests. The 5% diesel energy was injected near TDC to control CA50 at 10 °CA aTDC. While varying the split ratio between the two hydrogen injections, in-cylinder pressure/aHRR profiles, engine efficiency/power output and engine-out emissions of NOx and CO2 were evaluated. Results showed that the hydrogen split ratio does not significantly affect IMEP/efficiency, which
Zhao, Yifan, Chan, Qing Nian, Kook, Sanghoon
The Impact of Various Renewable Hydrocarbons on Performance and Emissions in a Super Lean Burn Engine2026-01-03064/7/2026
Compared to regular fuels, biofuels can play a key role as low-carbon transitional energy sources for ICE vehicles as the fleet moves towards increasing electrification. Blending of ethanol plays a key role in enhancing the anti-knock properties of the fuel and also allows renewable hydrocarbons (such as bio-naphtha) to be incorporated into the blend whilst maintaining an acceptable overall fuel quality. Super lean burn ICE technology with λ between 2 and 3 can lead to enhanced fuel economy and reduced NOx emissions. The Toyota prototype engine used to generate data for this project injects most of the fuel in PFI mode to generate a homogeneous super-lean charge in the cylinder, but just before spark ignition the DI injector sprays a small amount of fuel towards the spark plug to create a richer charge near the spark plug to promote flame kernel development. Various fuel formulations with high biofuel content were tested in both conventional and super lean burn engines. Certain fuel
Aradi, Allen, Krueger-Venus, Jens, Jain, Sandeep Kumar, Cracknell, Roger, Kolbeck, Andreas, Shibuya, Masahiko, Yamada, Ryota, Matsubara, Naoyoshi, Kitano, Koji
Physics-Based Simulation for Sustainable Fuels Part 2.1: Inter-Ring Pressure Measurements and 2D/3D Ring Dynamics Analysis across Multiple Engine Platforms – Light Vehicle2026-01-02814/7/2026
The growing demand for sustainable mobility and transportation is accelerating the adoption of alternative fuels, particularly hydrogen, in internal combustion engines. The first part of this publication series highlights the significance of 2D simulation as a crucial and computationally efficient tool for the precise development of hydrogen Power Cylinder Units. This approach demonstrates predictive capability proofed through engine tests, achieving a reduction in lube oil consumption by 5 g/h during high-load operations, alongside a 28% decrease in blow-by and an 11% reduction in hydrogen flow to the crankcase. To provide deeper insights into the complexities identified in Part 1, this study employs inter-ring pressure measurements across various engine types and configurations, including light vehicles, heavy-duty trucks, and large-bore applications, covering a broad range of engine displacements from 2 to almost 100 liters. This investigation in Part 2.1 focuses on understanding
Moreira, Rui, Köser, Philipp, Rösch, Hannes, Ehnis, Holger
Effects of the Spark Location and Timing in a Heavy-Duty Hydrogen-Fueled Engine2026-01-03314/7/2026
The use of hydrogen in internal combustion engines offers a promising route to lower-carbon propulsion in heavy-duty transportation. However, its distinct combustion characteristics as high flame speed, wide flammability limits, and susceptibility to abnormal combustion, necessitate careful engine and ignition system design. This study numerically investigates the combined effects of spark plug (SP) location and ignition timing on the performance of a heavy-duty diesel engine converted to spark-ignition and operated with hydrogen as fuel at reduced compression ratio. The numerical study aims to guide engine design. Three-dimensional computational fluid dynamics simulations with detailed hydrogen chemistry were conducted to evaluate flame development, and relevant combustion metrics under different loads. Model validation against engine combustion data and hydrogen injection from a low-pressure, high-mass-flow direct injector are also presented. The results demonstrate that SP placement
Menaca, Rafael, Shakeel, Mohammad Raghib, Panithasan, Mebin, Liu, Xinlei, Qahtani, Yasser, AlRamadan, Abdullah, Cenker, Emre, Silva, Mickael, Pei, Yuanjiang, Turner, James, Im, Hong
A Study on Fatigue Life Prediction Method for Point-Based Joints Considering Multiple Fracture Modes – FDS, Blind Rivet, and Blind Nut Focus2026-01-01804/7/2026
The application of multiple materials in vehicle bodies is accelerating as the adoption of lightweight aluminum alloys and composite materials advances rapidly. These materials play a crucial role in reducing overall vehicle weight, enhancing fuel efficiency, and complying with increasingly strict environmental regulations. As the automotive industry continues to evolve toward electrification and sustainability, the integration of lightweight and high-performance materials has become a key design strategy. However, the use of multiple materials creates new challenges in manufacturing, particularly for joining technologies. Since different materials have varying mechanical properties, thermal behavior, and surface characteristics, the selection of appropriate joining methods is essential for ensuring structural integrity and durability. Depending on material types, thicknesses, production processes, and cost constraints, various joining techniques—such as mechanical fastening, welding
Takuno, Sougo, Isono, Toshiyuki, Urakawa, Kazushi, Goto, Suguru, Kawamura, Hiroaki, Niisato, Eita, Ishigami, Yuta
Standardization of On-Vehicle Measurement of BEV Thermal System Energy Consumption and Range Impacts2026-01-01324/7/2026
This paper presents research and digital twin modeling results to support work on a methodology to properly account for the energy consumed by the thermal system of a BEV, for use within both existing Petroleum-Equivalent Fuel Economy (PEFE) calculations, and the proposed addition of hot and cold weather range values to the consumer-facing Monroney label [1]. Properly accounting for thermal system impacts would incentivize minimizing energy consumption of these systems, since 1) BEV PEFE is a direct input to an OEMs overall CAFE performance, and 2) the values on the Monroney label has some impact on consumer vehicle choice. The impetus for this work was Final Rules issued by the EPA and NHTSA in early 2024 eliminating A/C Efficiency Credits for BEVs from the 2027 MY, thus eliminating regulatory incentives to minimize energy consumption of these systems. Higher energy consumption will produce a number of negative secondary effects, including higher real-world greenhouse gas emissions
Taylor, Dwayne
Experimental Study of Hydrogen Combustion in Argon-Oxygen Mixture Using an Optical Engine2026-01-03284/7/2026
The Argon Power Cycle (APC) is an emerging high-efficiency combustion technology for internal combustion engines. In APC, the conventional air-based working fluid is replaced with an inert argon gas. This substitution inherently increases engine efficiency through thermodynamic properties of argon, in particular a high adiabatic factor ?? ~1.67. A hydrogen-fueled APC engine offers the potential for highly efficient zero emission combustion by also eliminating nitrogen oxide (NOx) formation. In the present paper, hydrogen combustion is studied in an optical heavy-duty research engine, with the objective of providing the first visualization of H2 combustion in an argon–oxygen mixture. A comparative analysis of high-speed optical imaging and in-cylinder pressure measurements is conducted for two different modes: 1) conventional air operation and 2) argon-oxygen mixture operation. The high-speed images reveal a distinctly different combustion process between the two operating modes. The
Kapp, Joakim, Cheng, Qiang, Kaario, Ossi, Vuorinen, Ville
Application of Topology Optimization to Production-Ready Passenger Seat Components Design2026-01-04984/7/2026
Lightweighting of components has become a key challenge in the development of modern transportation systems. In the automotive and aerospace industries, the overall mass of a vehicle has a significant impact on its fuel efficiency and manufacturing cost. Therefore, the lightweight design of vehicle components is crucial in the industrial field. Topology optimization (TO) is a computational design approach aimed at achieving lightweight designs. However, most existing studies focus on simplified academic models, with limited demonstration in real-world applications. This paper presents a revised TO workflow to obtain production-ready design and a practical implementation of TO in the design of three structural components in the aerospace industry: seatback frame, seat fuselage mount, and seat spreader. The revised TO workflow incorporates the practical demands of industry, including enhanced manufacturability and cost efficiency through TO design. The resulting designs are evaluated to
Lee, Hanbok Jake, Shi, Yifan, Gray, Savannah, Orr, Mathew, Park, Taeil, Wotten, Erik, LeFrancois, Richard, Huang, Yuhao, Patel, Anuj, Kim, Hansu, Jalayer, Shayan, Burns, Nicholas, Hansen, Eric, Grant, Robert, Kok, Leo, Kim, Il Yong
Effect of Injector Tip Temperature on Methanol Spray Dynamics during Cold-Start Conditions2026-01-03404/7/2026
Methanol is one of the most readily produced e-fuels and remains in liquid form at ambient conditions, making storage and transportation relatively simple. In the marine sector, methanol has already been actively adopted as a pathway toward carbon neutrality. For automotive sectors, methanol offers significant potential for carbon emission reduction owing to its higher octane number and lower carbon content compared with gasoline. However, its high latent heat of vaporization and low vapor pressure suppress evaporation at low ambient temperatures, leading to increased emissions during cold-start operation. To address this issue, previous studies have explored heating the injector tip or fuel rail to enhance evaporation and atomization. The present study focuses on visualizing and quantifying the improvement in methanol evaporation characteristics under cold-start conditions by applying controlled heating to the injector tip. Experiments were conducted in a constant-volume chamber where
Lee, Seungwon, Kim, Hyunsoo, Bae, Sumin, Hwang, Joonsik, Bae, Choongsik
Study of Deposit Control Additive Efficacy in Gasoline Direct Injection Engines2026-01-03494/7/2026
There is an increasing adoption of Direct-Injection Spark-Ignition (DISI) engines in the market, which per 2024 US Environmental Protection Agency (EPA) Automotive Trends Report represents 73% of new vehicles sold in the US. And while it is well accepted that DISI offers advantages over Port Fuel Injection (PFI) technology in meeting stringent CO2 emissions and fuel economy requirements set by the EPA, DISI engines are also associated with increased formation of injector deposits. These deposits may foul injectors and accumulate on the injector tip causing distorted spray patterns and diffusive combustion. Ultimately, this leads to engine performance deterioration and increased harmful emissions. To control deposit formation, detergent-type chemistries are added to the fuel in small amounts. Deposit Control Additives (DCAs) function by preventing the formation of deleterious injector deposits as well as removing existing ones. This study used standardized protocols describing the
Soriano, Nestor, Williams, Rod, Cracknell, Roger, Lang, Wendy, Chahal, Jasprit
Development and Preliminary Combustion Experiments of a Prototype Engine with Sleeve Valves Based on the Focusing Compression Principle2026-01-02954/7/2026
Our laboratory has proposed the focusing compression principle which employs pulsed super-multi jets of gas colliding around the chamber center. This principle aims to achieve high thermal efficiency by reducing both exhaust and cooling losses. Exhaust loss is minimized due to relatively-silent high compression. Cooling loss is reduced due to thermal insulation caused by fuel-air mixture being confined to the chamber center and the compressible flow effect. In previous studies, we conducted fundamental gasoline combustion experiments on a proof-of-concept opposed-piston engine which incorporated this principle. This engine featured eight intake nozzles in an octagonal configuration and utilized non-sinusoidal and strongly asymmetric piston movements. The results indicated the possibility of high thermal efficiency based on less knocking under high compression, and the potential for stable combustion under lean-burn conditions. As a next step towards practical application with
Nishizawa, Tomohiko, Naitoh, Ken, Baba, Shotaro, Ukegawa, Hiraku, Yamada, Sota, Ozono, Yuka, Abiko, Mirei, Suzuki, Yosuke, Hara, Namito, Ito, Yoshikuni, Matsubara, Kosaku, Uenoyama, Kazuyuki
Simulation of Conjugate Heat Transfer using the Lattice Boltzmann Method2026-01-01354/7/2026
Flow simulation with conjugate heat transfer, which involves fluid flow, conduction, and radiation within solid components, is a vital capability that enables engineers to design and assess cooling systems for heat-producing parts such as brakes, powertrains, batteries, and power electronics in both gasoline and electric vehicles. In this study, we employ PowerFLOW®, which features a thermal solver capable of simultaneously modeling both fluid and solid domains within a unified framework. The fluid flow is simulated using the Lattice Boltzmann Method (LBM) with VLES turbulence modeling based on the RNG k–ε approach. The solid domain is solved using a finite volume method with second-order accuracy for thermal conduction, combined with surface-to-surface radiation modeling for thermal exchange between surfaces. This integrated approach streamlines the simulation workflow while enabling accurate representation of both conduction and radiation phenomena. We assess the accuracy of the
Mukutmoni, Devadatta, Shock, Richard, Li, Han, Wanderer, John, Gopalaswamy, Nath, Miao, Ling
Multi-Objective Reinforcement Learning Framework for Transmission Shift Schedule Optimization2026-01-01624/7/2026
Building upon previous work that successfully employed a Reinforcement Learning (RL) agent for the autonomous optimization of transmission shift programs to enhance fuel efficiency, this paper addresses a critical limitation of that approach: the neglect of human-centric factors. While the prior methodology achieved substantial fuel consumption reductions by training an RL agent in a Software-in-the-Loop (SiL) environment, it did not explicitly account for aspects such as driver comfort and preferences, which are paramount for real-world user acceptance and drivability. This work presents a multi-objective optimization framework extending the artificial calibrator to simultaneously maximize fuel efficiency and enhance driver comfort. The method introduces a modified RL reward function that penalizes undesirable shift behavior to ensure a smooth driving experience (drivability). This new methodology also incorporates a mechanism to capture and integrate driver preferences, moving beyond
Kengne Dzegou, Thierry Junior, Schober, Florian, Rebesberger, Ron, Henze, Roman, Sturm, Axel
Combustion Characterization of Hydroprocessed Esters and Fatty Acids (HEFA) as an Alternative Fuel for Use in IC Engines2026-01-03174/7/2026
In the endeavors to reduce reliance on fossil fuels and reduce greenhouse gas emissions, synthetic fuels from less carbon intensive feedstocks have emerged as a promising alternative to conventional fuels. These synthetic fuels have gained traction in the aviation industry as sustainable aviation fuels (SAFs). One such fuel is a synthetic paraffinic kerosene derived from hydroprocessed esters and fatty acids (HEFA). Preliminary research has also suggested that this fuel may also be favorable for use in IC engines. This investigation will explore the combustion characteristics of HEFA in an IC engine in more detail. The thermophysical properties of HEFA were investigated and found comparable to or improving upon those of ULSD. Spray atomization analysis revealed more than 25% smaller SMD compared to ULSD, and lower span factor indicating a more uniform spray which can promote faster formation of a homogenous mixture. A tribological analysis using a pin-on-disk tribometer revealed
Soloiu, Valentin, Willis, James, Norton, Coleman, Davis, Zachary, Peralta Lopez, Guillermo, Rahman, Mosfequr
Automotive Aerodynamics Surrogate Modeling using NVIDIA PhysicsNeMo on Mid-Sized SUV GM Dataset2026-01-06004/7/2026
Aerodynamic simulations are crucial in vehicle design and performance evaluation. Traditionally, these simulations utilize Computational Fluid Dynamics (CFD) techniques to compute flow quantities such as velocity, pressure, and wall-shear stresses. Accurate prediction of these quantities is vital for estimating drag and lift forces, which directly impact fuel efficiency, stability, and acoustics. This study focuses on developing an AI surrogate for aerodynamic design of production mideo-size SUVs using NVIDIA’s PhysicsNeMo framework. Firstly, high-fidelity 3D CFD data are generated using first-principles solvers on 102 different geometry variants at a uniform inlet velocity of 38.89 m/s and a fixed set of boundary conditions. The DoMINO (Decomposable Multiscale Iterative Neural Operator) AI model, part of the PhysicsNeMo framework, is then used to train on this dataset, accurately predicting surface pressure and flow fields around vehicles for rapid estimation of critical aerodynamic
Keum, Seunghwan, Raul, Vishal, Grover, Ronald, Parrish, Scott, Ranade, Rishikesh, Ghasemi, Abouzar, Kamenev, Alexey, Tadepalli, Srinivas
The Impact of Mid-Level Ethanol Blends on Reliability, Performance and Emissions in Gasoline Engine2026-01-03024/7/2026
To reduce CO₂ emissions from automobiles, it is essential to improve system efficiency through the electrification of vehicles with internal combustion engines (ICEs), such as hybrid electric vehicles (HEVs) and plug-in hybrid electric vehicles (PHEVs), as well as through enhancements in ICE thermal efficiency. Additionally, biofuels and synthetic fuels are gaining attention as promising options to reduce CO₂ emissions from existing vehicles. Among these alternative fuels, ethanol, a bio-derived fuel, is already used at varying concentrations in many countries, and its further adoption is expected. Expanding the fleet of flex-fuel vehicles (FFVs) capable of running on high ethanol blends is one approach; however, increasing ethanol content in conventional gasoline, which is more widely used, is considered to have a greater impact on CO₂ reduction. A key issue is how existing vehicles adapt to increased ethanol concentrations such as E20, E30, and E40. This study focuses on turbocharged
Matsubara, Naoyoshi, Sugata, Kenji, Koyama, Takashi, Ochi, Yuta, Aoki, Mizuki, Hashima, Takashi, Kodama, Kohei, Tomoda, Keiju, Kojima, Masakiyo
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