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This work examines the regenerative braking capacity using different torque distribution strategies for an independent-axle all-wheel-drive electric vehicle. A single-motor rear-wheel drive Cadillac LYRIQ provided by General Motors and modeled by MathWorks is being modified into an all-wheel drive architecture. The architecture under study has independently driven front and rear axles, driven by a 50 kW (peak power) front motor and a 182 kW (peak power at 350V) rear motor. The goal of the study is to evaluate and compare the regenerative braking capacity for different regenerative braking strategies. This study aims to assist in the development of the energy management algorithm for the Propulsion Supervisory Controller (PSC). Firstly, two variants of optimal regenerative torque distribution strategies are studied. One without power rate penalties and the other with a power rate penalty.

The objective of the project was to evaluate the energy efficiency of a hybrid electric tractor-semi-trailer combination prototype. The prototype was developed for log hauling application by integrating an existing tractor with an electric semi-trailer to improve fuel consumption and reduce greenhouse gas emissions. One of the conventional axles of the quad axle semi-trailer was replaced with a drive axle powered by an electric motor. Tests were conducted on a 105 km test route with a maximum difference in elevation of 355 m, including a hilly section with a length of 89 km. The results indicated fuel savings ranging from 10.5% to 14% per test run, with an average fuel savings of 12% when the electric drive axle was engaged. The hybrid electric tractor semi-trailer consumed 17.5% less fuel up-hill and 9.4% less down-hill. Throughout each test run, the battery’s state of charge fluctuated, averaging between 88% at the start and 52% at the end.

Recuperated low-pressure-ratio split-cycle engines represent a promising engine configuration for applications like transportation and stand-alone power generation by offering a potential efficiency as high as 60%. However, it can be challenging to achieve the stringent NOx emission standard, such as Euro 6 limit of 0.4 gNOx/kWh, due to the exhaust cylinder high intake temperature. This paper presents experimental investigation of hydrogen-air combustion NOx emissions for such engines for the first time. Experiments are carried out using a simplified constant-volume combustion chamber with glow-plug ignition. Two fuel injection techniques are performed: direct injection and injection via a novel convergent-divergent injector. For the direct injection scenario, NOx levels are unsatisfactory with respect to the Euro 6 standards over a range of operating temperatures from 200 °C to 550 °C.

Because it can be produced in a green form, methanol is envisioned as a potential fuel to replace conventional diesel fuel and directly reduce the greenhouse gas (GHG) impact of maritime transportation. For these reasons, Original Equipment Manufacturers (OEMs) working on marine applications are focusing on making methanol easily usable in Compression Ignition (CI) engines. While it is an easy-to-use substance with manageable energy content, methanol has a few drawbacks, including a high latent heat of vaporization and a high auto-ignition temperature, all of which affect combustion quality. Therefore, solutions have been found or are still under study to give it Diesel-like behavior. One solution is to use a pilot fuel for ignition in significant quantities. A previous study conducted at the PRISME laboratory highlighted the possibility of using a Combustion Enhancer based on Nitrates (CEN) as an additive.

Modern automotive powertrains are operated using many control devices under a wide range of environmental conditions. The exhaust temperature must be controlled within a specific range to ensure low exhaust-gas emissions and engine-component protection. In this regard, physics-based exhaust-temperature prediction models are advantageous compared with the conventional exhaust-temperature map-based model developed using engine dyno testing results. This is because physics-based models can predict exhaust-temperature behavior in conditions not measured for calibration. However, increasing the computational load to illustrate all physical phenomena in the engine air path, including combustion in the cylinder, may not fully leverage the advantages of physical models for the performance of electric control units (ECUs).

The automotive industry faces significant obstacles in its efforts to improve fuel economy and reduce carbon dioxide emissions. Current conventional automotive powertrain systems are approaching their technical limits and will not be able to meet future carbon dioxide emission targets as defined by the tank-to-wheel benchmark test. As automakers transition to low-carbon transportation solutions through electrification, there are significant challenges in managing energy and improving overall vehicle efficiency, particularly in real-world driving scenarios. While electrification offers a promising path to low-carbon transportation, it also presents significant challenges in terms of energy management and vehicle efficiency, particularly in real-world scenarios. Battery electric vehicles have a favorable tank-to-wheel balance but are constrained by limited range due to the low battery energy density inherent in their technology.

The American Petroleum Institute’s (API) Single Technology Matrix (STM) is a data-based, Virtual Testing process and protocol (utilizes test data, characteristics and features of base stocks and blends coupled with statistical methods and analysis) used to predict the performance capability of a specific engine oil additive technology in a single specified base oil, in a given engine test. The concept was first introduced in 2002, codified and implemented by API in 2007, and updated in 2022. The previously published advantages of STM in the proof-of-performance of engine oils, remain relevant. These advantages include a data space focused on interpolation, documented statistical analysis protocol, limitation to a specific formulation, flexibility in understanding complicated, interactive, or non-linear technology and base oil relationships, and timeliness. There have been numerous changes to, and in, the engine oil industry since the introduction of STM in 2007.

To realize a super-leanburn SI engine with a very-high compression ratio, it is required to design a new fuel which could have low ignitability at a low temperature for antiknocking, but high ignitability at a high temperature for stable combustion. Ethane shows a long ignition delay time at a low temperature close to that of methane, but a short ignition delay time at a high temperature close to that of gasoline. In the present study, the antiknocking effect of adding methane with the RON of 120, ethane with the RON of 108, or propane with the RON of 112 to a regular gasoline surrogate fuel with the RON of 90.8 has been investigated. Adding each gaseous fuel by less than 0.4 in heat fraction advances knocking limit in the descending order of SI timing advance of ethane, methane, and propane, and in the descending order of CA 50 advance of ethane, propane, and methane. Adding methane extends combustion duration slightly, but adding ethane or propane shortens it considerably.

For the survival of internal combustion engines, the required research right now is for alternative fuels, including drop-ins. Certain types of alternative fuels have been estimated to confirm the superiority in thermal efficiency. In this study, using a single-cylinder engine, olefin and oxygenated fuels were evaluated as a drop-in fuel considering the fuel characteristic parameters. Furthermore, the effect of various additive fuels on combustion speed was expressed using universal characteristics parameters. In addition, the prediction of CO2 emission from passenger cars were carried out by changing the fuels. The CO2 emission in running WLTC was estimated using Modelica. As a result, it was found that the CO2 emission can be reduced by adding olefin and oxygenated fuels.

Abstract Engine brakes are more effective in braking a heavy-duty vehicle during deceleration compared to the traditional clutch-brake system. Therefore, commercial vehicle OEM’s along with regulations, demand the acclimatizing of engine brake (EB) system. To achieve this, it is equally important to adopt to variable valve actuation dynamic valvetrain (VT) system. To help develop these systems, Model Based Product Development approach is used primarily at Eaton. In current work, the effect of valve lash sensitivity on EB performance and VT dynamics is studied using multi physics GT-SUITE models. This helps to understand the impact of lash on valve lift opening, lift loss and overall VT system compliance. In addition to above VT dynamics, its effect on EB power is also studied. This is done using a medium duty 6-cylinder GT-POWER engine model developed from Fast Response Model (FRM) database.

In the quest for reduced development times and cost of fuel cell systems for industrial applications, we identified two major issues. First, the electrochemical behaviour of fuel cell systems is inherently difficult to predict. Second, testing fuel cell systems is resource intensive. These issues compound: Setting up an accurate model of a fuel cell system incurs long testing periods and does not guarantee acceptable results outside the tested parameters or for other membrane electrode assembly compositions. Our proposal to mitigate these two major issues is the use of an X in the Loop concept. Essentially, this is the direct integration of the test sample, here a single fuel cell, into the modelling environment of the whole system. In practice, we have defined two strategies with different levels of integration. Both assume a required power profile is given.

In the field of polymer electrolyte membrane fuel cells (PEMFC), significant research has focused on the membrane electrode assembly (MEA) and electrochemical characterization methods. For real applications optimizing the fuel cell system (FCS) design is essential, requiring careful monitoring of electrochemical and thermodynamic process parameters such as pressure, temperature, relative humidity, heat flux, and gas composition. These operating conditions, provided by balance of plant (BoP) components, significantly impact FCS efficiency, especially relative humidity, which demands high energy input. The first step in a system development involves comprehensively characterizing the MEA by mapping a wide range of operating parameters, not just peak performance points, which are not necessarily the most beneficial for the FCS. This requires precise and dynamic adjustments of process parameters during testing to capture all relevant data efficiently.

Nowadays, a lot of vehicles install the autonomous technologies. However, we cannot evaluate the fuel economy and the emissions of these vehicles, which is working the autonomous technologies. The reason is that it is difficult to estimate it of these vehicles by using the chassis dynamometer. Therefore, we studied the new test procedure of the fuel economy and the emissions for these vehicles, which is working the Adaptive Cruise Control (ACC) function. To be specific, we use two vehicles and execute the real driving test. The leading vehicle operates by the driving robot. This vehicle drives the WLTC (Worldwide Harmonized Transient Cycle) and RDE (Real Driving Emission) mode with accuracy. And the following vehicle drives by operating the ACC function, which is the Level 2 of the autonomous technologies. In this report, firstly, we produced the driving robot for the RDE test.

Next generation lubricating oils for transportation sector require higher durability in operation, compatibility with new engine technologies, aftertreatment devices and fuel economy (FE) characteristics, thus contributing to the reduction of CO2 emissions, both in passenger cars and heavy-duty vehicles. The current paper aims to highlight the impact of dispersant technologies for their main properties, that are preventing sludge and deposits formation on engine surfaces, and in regard to the effect on frictional properties of lubricating oils, through a multi-step activity. Oil contamination by soot is a big concern not only for diesel but also for new generation of direct injection gasoline (GDI) engines. The presence of soot leads to oil thickening that heavily impacts on friction coefficient thus enhancing the role of dispersant in controlling soot and related viscosity increase and, indirectly, fuel consumption for long running periods.

A power steering system is a component that helps the heavy-duty operator to move easily the vehicle by the hydraulic pump providing the fluid pressure and facilitating adequate operation. Some failures in the power steering system are due to external and internal factors that can reduce its life. The external factor could be identified by ocular inspection but normally to internal failures is necessary to use a hydraulic pressure flow meter. However, with this device is impossible to detect failures by the lubricant selected. This work aims to investigate the causes of power steering system seizure by using the tribological wear examination process and the lubricant characterization under some actual operation conditions.

Vehicle electrification has emerged as a pivotal area of research across diverse industries. When applied to heavy-duty vehicles (i.e., school buses), it presents a unique opportunity for the automotive sector to lead sustainability efforts. Beyond energy savings, the electrification of school buses offers advantages such as improved children's health, reduced greenhouse gas emissions, and enhanced green vehicle routing, inspiring broader adoption of eco-friendly practices. This study primarily aims to analyze the energy-saving effects and economic viability resulting from the electrification of existing school bus routes. Specifically, the research examines the drive cycles of operational bus routes and evaluates the energy demand and cost implications associated with transitioning from conventional buses (diesel buses) to electric buses or other alternative powertrains for fleet operations.

Inadequately designed flow field layouts in bipolar plates within Proton Exchange Membrane fuel cells (PEMFCs) may lead to ineffective water removal and impede reactant transport. This work examines the typical flow channel designs found in bipolar plates of fuel cells and implements modifications to certain designs to alleviate pressure drops within the flow channels using computational fluid dynamics (CFD) analysis. These designs are optimized by changing different parameters such as size of the channel and rib width utilizing Taguchi L27 standard orthogonal array. The resultant reduction in pressure drop is anticipated to enhance the overall performance of the fuel cell. The optimal flow field design of bipolar plates (Graphite and Aluminum) are manufactured using CNC milling. Tests evaluating flexural strength, surface roughness, hardness, contact angle, and corrosion resistance are conducted to assess and compare the performance of these plates.

A digital twin is a digital representation of a planned or real physical system, product, or process that functions as its practically identical digital counterpart for tasks such as testing, integration, monitoring, and maintenance. Creating digital twins allows the ‘digital system’ or ‘digital product’ to be tested faster-than-real-time improving overall efficiency and reducing time of a programme. The HORIBA Intelligent Lab virtual engineering toolset was used produce an empirically based digital twin of a contemporary off-highway diesel Internal Combustion Engine (ICE). These empirical models were then coupled with simulations developed by AgriSI and IPG CarMaker to predict performance and emissions for real-world machine handling cycles of off-highway machines such as ploughing, planting, weeding, and fertilising.

Waste cooking oil can be converted into fuel for internal combustion (IC) engine applications by transesterification or pyrolysis. Transesterification results in the production of fatty acid methyl esters called biodiesel. The variability in biodiesel composition and properties from diesel fuel leads to engine re-calibration that requires significant time and effort. Diesel-like hydrocarbons can be produced by catalytic pyrolysis of used cooking oil. Such fuel can be used as a drop-in fuel in IC engine applications. Hydrogen at high pressures and a catalyst generally promote deoxygenation during pyrolysis. Recently, novel heterogenous acid catalysts such as Ni-impregnated activated carbon (AC) and Ag-Co-impregnated AC catalysts were developed to produce deoxygenated fuel by pyrolysis at atmospheric pressure without using hydrogen. Homogenous base catalysts such as sodium hydroxide can also be used in pyrolysis to produce diesel-like fuel.

Accurate flywheel torque estimation in combustion engines can be used for monitoring engine performance, creating the potential for lowering emissions and fuel costs. Recently a method was proposed to determine the mean flywheel torque from instantaneous engine speed using the n-th order Fourier series, where n is the number of cylinders firing per crank revolution. However, instantaneous engine speed is affected by two separate torque contributions. The torque resulting from reciprocating masses in the engine, i.e., reciprocating torque, and the torque produced by combustion pressure, i.e., gas torque. Gas torque and reciprocating torque signals have the same frequency but are in opposite phases. Since the resultant torque at the flywheel is the sum of gas and reciprocating torques, there is a need to remove reciprocating torque from the total torque at the flywheel. This requires knowing whether gas or reciprocating torque has a larger amplitude.