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This study focuses on evaluation of various fuels within a conventional gasoline internal combustion engine (ICE) vehicle and the implementation of advanced emissions reduction technology. It shows the robustness of the implemented technology packages for achieving ultra-low tailpipe emissions to different market fuels and demonstrates the potential of future GHG neutral powertrains enabled by drop-in lower carbon fuels (LCF). An ultra-low emission (ULE) sedan vehicle was set up using state-of-the-art engine technology, with advanced vehicle control and exhaust gas aftertreatment system including a prototype rapid catalyst heating (RCH) unit. Currently regulated criteria pollutant emission species were measured at both engine-out and tailpipe locations. Vehicle was run on three different drive cycles at the chassis dynamometer: two standard cycles (WLTC and TfL) at 20°C, and a real driving emission (RDE) cycle at -7°C.

As a novel ignition technology, pre-chamber ignition can enhance ignition energy, promote flame propagation, and augment turbulence. However, this technology undoubtedly faces challenges, particularly in the context of emission regulations. Of this study, the transient characteristics of combustion and emissions in a hybrid electric vehicle (HEV) gasoline engine with active pre-chamber ignition (PCI) under the first combustion cycle of quick start are focused. The results demonstrate that the PCI engine is available on the first cycle for lean combustion, such as lambda 1.6 to 2.0, and exhibit particle number (PN) below 7×107 N/mL at the first cycle. These particles are predominantly composed of nucleation mode (NM, <50 nm) particles, with minimal accumulation mode (AM, >50 nm) particles.

With the rapid development of electric vehicles (EVs), lithium-ion batteries (LIBs) with high energy and power density have been widely applied as the power producer of EVs. However, the range of EVs has been criticized. To meet consumer demand for high power and long driving distances, the energy and power density of LIBs are getting higher and higher. However, LIBs with higher energy density are more prone to catastrophic thermal runaway (TR). In recent years, EV accidents due to TR of LIBs have been frequently reported, which makes consumers lose confidence in EVs. To solve the problem, we must understand the mechanism of LIBs TR, thereby reducing the likelihood of TR in EVs. However, the induction mechanism of LIB TR induced by mechanical abuse is sophisticated. This paper focuses on recent advances in the study of thermal TR characteristics of batteries caused by mechanical abuse, including bending, collisions, and penetration.

Designing for fatigue performance requires extensive knowledge of material properties, component geometry and dynamic loading conditions. These topics are addressed in an ongoing cohesive research program on fatigue behavior of magnesium die castings. The current phase of the program includes effects of alloy type, mean stress level, surface condition, and level of tensile properties. The results, presented as S-N curves and Goodman diagrams, show a significant difference in the fatigue life between AZ91D and the AM alloys. Fatigue behavior of AM60B was strongly dependent on the mean stress level, but was not significantly influenced by a minor difference in casting quality. The fatigue behavior of AM50A was not noticeably changed by the addition of vibratory polishing.

Efficiency of Driveshafts have not been analyzed in great detail in the past due to their relatively high efficiency. However, it is possible to obtain about a 0.1 percent increase in fuel economy by decreasing driveshaft torque losses by about 20 percent, owing to the combination mode fuel calculation. In order to improve fuel economy it is necessary to increase the efficiency of the constant velocity universal joint (C.V.J.) used for driveshafts. Additionally, propeller shafts with improved heat characteristics are required. It is for these reasons that this project is conducted. In this paper, the motion of two typical joint used for front-engine, front-drive passenger cars is analyzed geometrically and efficiency formulas are derived. One of the joints is a Rzeppa joint, used on the wheel side of the driveshaft and the other is a tripot joint, used on the differential side. These formulas are then verified by experiment.

This paper describes an experimental and epidemiological investigation of the potential application of a specific rollover occupant protection system, consisting of a rollover protective structure and occupant restraint (collectively referred to hereafter as ROPS), to all-terrain vehicles (ATVs). The ROPS investigated in this paper was proposed by Dahle [1987] as a means to improve the safety of ATV operation. Crash tests were performed with an unhelmeted instrumented dummy on 4-wheel ATVs equipped with the prototype Dahle ROPS (hereafter referred to as D-ROPS); the test results established that the D-ROPS design exhibited the potential for serious injury or death in lateral rollover, rearward pitchover, collision, and oblique frontal impact accident scenarios. Review of ATV-associated 1986 fatality reports from the U.S.

Volvo has developed the first production emission control system to fully utilize a three-way catalyst. Called the “Volvo Lambda-sond system”, it is applied to the 4-cylinder in-line B21 engine, and employs three essential new components - an exhaust gas composition sensor, an additional feed-back loop to the continuous fuel injection system, and the catalyst. Outstanding certification results were achieved, especially for NOx, combined with good driveability, power output, and fuel economy. The development and performance of the system, and the test procedures used, are described in detail, and its future potential and limitations are discussed.

The development of a modern transportation product requires that the safety of the product be considered at every stage of its life, from initial design to ultimate product disposal. Virtually all of the decisions that can positively effect product safety are made during the product design stage with most of the critical decisions being made early in the process. As a result, early incorporation of system safety into the design process has been shown repeatedly to result in safer products. Incorporation of formal system safety programs into ground transportation vehicle design programs is comparatively recent. Historically, in both the automotive and the heavy goods vehicle industry, product safety has been provided through consistent over design of evolutionary system elements to ensure correct functioning under repeated exposure to worst case stresses.

The deionized water/ethylene glycol coolant used in the Ford Focus Fuel Cell Vehicle (FCV) requires very low conductivity (< 5 μS/cm) to avoid current leakage and short circuiting, presenting a unique water chemistry issue. The coolant's initially low conductivity increases as: 1) ions are released from system materials through leaching, degradation and/or corrosion, and 2) organic acids are produced by ethylene glycol degradation. Estimating the leaching potential of these ions is necessary for design and operation of fuel cell vehicles. An on-board mixed-bed, ion exchange resin filter is used to maintain low conductivity by removing leached or produced ions. Various candidate materials were evaluated for leaching potential by exposing them to coolant at the design operating temperature for several months and periodically analyzing the coolant for ions.

The increasing trend of automotive electronics mandates the introduction of multiple processors in automotive electronics. The automotive electronic systems have to operate in harsh environments having a high temperature range, high humidity, unpredictable vibrations and rapid voltage variation. In such environment, the automotive electronic systems become vulnerable to intermittent and transient failures. Depending upon the importance of the tasks performed by the processor, a processor’s failure inside automotive electronic system may lead to serious consequences. Fault tolerant computing techniques are used to keep the computer systems running in spite of one or more processors’ failures. The concept of fault tolerant is well known in many applications such as airplanes, industry, and military. However, the question of fault tolerant design has drawn little attention in automotive electronics.

While the CAN Calibration Protocol or CCP is a reasonably well known standard in Europe that continues to gain acceptance, its exposure in the American automotive electronics arena has to some extent been limited to the engine calibration area. A closer examination of the protocol reveals that the CCP is not just for calibration. With many general-purpose features including flash programming capability, the CAN Calibration Protocol is useful for a wide range of module development activities. CCP users have access to online measurement data and the ability to calibrate modules. This allows software development to occur not only in a lab environment but also during an in-vehicle test. Even though U. S. companies using or evaluating the CAN Calibration Protocol include DaimlerChrysler, Ford, GM, Delphi, Motorola, TRW, Visteon, and several others, many product development engineers are unaware of this potentially reusable software.

In an ever-transforming sector such as that of private road transport, major changes in the propulsion systems entail a change in the perception of the noise sources and the annoyance they cause. As compared to the scenario encountered in vehicles equipped with an internal combustion engine (ICE), in electrically propelled vehicles the heating, ventilation, and air conditioning (HVAC) system represents a more prominent source of noise affecting a car’s passenger cabin. By virtue of the quick turnaround, steady state Reynolds-averaged Navier Stokes (RANS)- based noise source models are a handy tool to predict the acoustic power generated by passenger car HVAC blowers. The study shows that the most eminent noise source type is the dipole source associated with fluctuating pressures on solid surfaces.

In 2023, the European Union set more ambitious targets for reducing greenhouse gas emissions from passenger cars: the new fleet-wide average targets became 93.6 g/km for 2025, 49.5 g/km in 2030, going to 0 in 2035. One year away from the 2025 target, this study evaluates what contribution to CO2 reduction was achieved from new conventional vehicles and how to interpret forecasts for future efficiency gains. The European Commission’s vehicle efficiency cost-curves suggest that optimal technology adoption can guarantee up to 50% CO2 reduction by 2025 for conventional vehicles. Official registration data between 2013 and 2022, however, reveal only an average 14% increase in fuel efficiency in standard combustion vehicles, although reaching almost 23% for standard hybrids. The smallest gap between certified emissions and best-case scenarios is of 14 g/km, suggesting that some manufacturers’ declared values are approaching the optimum.

Aeroacoustics is important in the automotive industry, as it significantly influences driving comfort. Particularly in the case of battery electric vehicles (BEVs), the flow noise is already crucial at lower driving speeds, since these generate barely any drive noise and the masking effects produced by the engine are eliminated. Due to the increasing importance of drag minimization and elimination of the exhaust system, the underbody of BEVs is typically very streamlined and exhibits a low acoustic interference potential. However, even small geometric modifications to the vehicle can lead to changes in the flow around the vehicle and consequently to significant noise sources. Thus, significant flow resonances in the low frequency range below 30 Hz have been detected on certain vehicle configurations. Initial investigations have shown that the flow around the front wheel spoilers is relevant for the development of the flow phenomenon.

Testing techniques for creating rollovers have been a subject of much study and discussion, although previous work has concentrated on creating a repeatable laboratory test for evaluating and comparing vehicle designs. The two testing methodologies presented here address creating rollover tests that closely mimic a specific accident scenario, and are useful in accident reconstruction and evaluation of vehicle performance in specific situations. In order to be able to recreate accidents on off-road terrain, a test fixture called the Roller Coaster Dolly (RCD) was developed. With the RCD a vehicle can be released at speed onto flat or sloping terrain with any desired initial roll, pitch and yaw angle. This can be used to create rollover collisions from the trip stage on, including scenarios such as furrow trip on an inclined road edge.

The geometry of high-pressure pump and injector nozzles crucially influences hydraulic behaviors (e.g., the start of injection, the pressure profiles developed in the high-pressure line, needle lift, and injection rates) in diesel engines. These factors, in turn, significantly impact fuel atomization, fuel–air mixing, combustion quality, and the formation of emissions. The main geometry parameters such as plunger diameter and the number and diameter of nozzles lead to the system complexity, requiring careful analysis, design, and calibration. In this study, a high-speed shadowgraph system and a high-resolution pressure recording system were developed to capture the start of injection, spray structure, and pressure profiles in the high-pressure line. Additionally, a model was developed using GT-Fuel package built within the GT-Suite of simulation tools to explore different plunger diameters and numbers and diameters of injector nozzles.

Windshields, with their low internal damping, are an acoustical weak link in automotive glazing. In the past, acoustically-enhanced glass products were typically achieved by utilizing solid and mass product design elements to increase the glass thickness. This is no longer acceptable as automakers are interested in weight savings, especially as they develop vehicles that are more fuel-efficient. Laminated safety glass, with a standard polyvinyl butyral (PVB) interlayer, is used extensively for automotive windshields and side glazing, and offers improved acoustical performance over tempered glass. However, the standard PVB interlayer is not designed specifically for acoustical and Noise, Vibration and Harshness (NVH) purposes. Studies of the parameters affecting acoustical properties and actual noise reduction capability of standard laminated glass led to the development of an acoustical grade PVB interlayer.

There are exposures of the body to accelerations in the lumbar and thoracic regions on a regular basis with everyday activities and exercises. The purpose of this study was to evaluate the response of the thoracic and lumbar regions in human volunteers subjected to vigorous activities. A total of 181 tests include twenty volunteers subjected to four test scenarios: “plopping” down in a seat, a vertical jump, a vertical drop while in a supine position, and a vertical drop while seated upright in a swing. Each of the latter three activities included three severity levels with drop heights ranging from 25 mm to 900 mm. Volunteers selected represent the anthropometry of the general population including males and females at a wide range of weights (54 to 99 kg), heights (150 to 191 cm), and ages (26 to 58 years old). Instrumentation for each volunteer included tri-axial accelerometers attached to custom-fit mounts that were secured around the lumbar and upper thoracic regions.

Two models of a tractor-semitrailer combination are created based on vehicles used in a field operational test. One model is used for tilt table simulations and the other is supplied driving inputs from the field operational test at two dangerous road curves (“hotspots”). Dynamic rollover conditions are simulated for several hotspot trips and varying payload conditions by extrapolating the trip speed profiles. The dynamic rollover threshold from the vehicle simulations is shown to be, on average, about 25% lower than the static stability factor over the range of loading conditions. The difference between the critical speeds at rollover for the range of loading conditions is approximately 3 m/s.

Improving the energy balance of vehicles is an effective way of lowering CO2 emissions. Among other things, this does entail mounting demands on the power wiring system. The intention is, for instance, to adapt the drive train to facilitate such functions as more efficient recuperation, e-boost and sailing with the aid of a 48V starter generator and a 48V battery. In addition, it is a matter of electrifying mechanical components with the aim of energy-efficient demand management to save fuel. The 48V power wiring system as an addition to the 12V system is a promising option where the task is to make the low-voltage wiring system of vehicles in the mass-market segment more powerful. Raising system voltage to 48V has the effect of fundamentally improving the efficiency of electricity generation and power distribution in the vehicle because of the reduced current and therefore the diminished ohmic losses.