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Recently, regulations on automobile emission have been significantly strengthened to address climate change. The automobile industry is responding to these regulations by developing electric vehicles that use batteries and fuel-cells. Automobile emissions are environmentally harmful, especially in the case of vehicles equipped with high-temperature and high-pressure diesel engines using compression-ignition, the proportion of nitrogen oxides (NOx) emissions reaches as high as 85%. Additionally, air pollution caused by particulate matter (PM) is six to ten times higher compared to gasoline engines. Therefore, the electrification of commercial vehicles using diesel engines could potentially yield even greater environmental benefits. For commercial vehicles battery electric vehicles (BEVs) require a large number of batteries to secure a long driving range, which reduces their maximum payload capacity.

In recent years, with the advent of the Fourth Industrial Revolution and the COVID-19 pandemic, people's lives worldwide have undergone significant changes. Additionally, the emergence of a new generation of consumers known as the millennial generation has led to a high demand for multipurpose family cars. The perspective is shifting towards choosing premium products that enhance the quality of life and pursue their own happiness and comfort through technology, rather than simply selecting a midsize SUV based on the increase in family size. We aim to meet the needs of these global customers by conducting research and developing various new features that were not previously available in midsize SUVs. In this study, we defined the actual target users for midsize SUVs and established UX concepts by analyzing their characteristics. Based on this, we employed an optimal design approach by analyzing the evaluation results by country for the various features implemented within the vehicle.

As the carbon neutrality to reduce greenhouse gas emissions has become a global movement, the development of power sources using carbon-free fuels is an essential task for the industry. Accordingly, many companies in various fields that need carbon reduction are striving to develop power sources and build energy value chains using carbon-free or carbon-neutral fuels such as hydrogen and E-fuel. Ammonia, which is also a carbon-free fuel, stands as an efficient energy vector delivering high energy density and flexibility in transportation and storage, capable of mitigating hydrogen’s key drawbacks. However, difficulty of controlling combustion of ammonia due to its fuel characteristics limited the development of internal combustion engines using ammonia to the basic research stage in the limited operating conditions. Hyundai Motor Company presents the development of ammonia fueled 4-cylinder SI engine using direct injection strategy, designed based on 2.5L LPG T-DI engine.

This research addresses the pressing need for reducing vehicle aerodynamic resistance, with a specific focus on mitigating wheel and tire resistance, which constitutes approximately 25% of the overall vehicle drag. While the prevailing method for reducing resistance in mass production development involves wheel opening reduction, it inadvertently increases wheel weight and has adverse effects on brake cooling performance. To overcome these challenges, novel complementary resistance reduction methods that can be employed in conjunction with an appropriate degree of wheel opening reduction are imperative. In this study, we introduce symmetrical wheels with a fan-like shape as a solution. The fan configuration influences the surrounding flow by either drawing it in or pushing it out, depending on the direction of rotation. Application of these fan-type wheels to a vehicle's wheels results in the redirection of flow inwards or outwards during high-speed driving due to wheel rotation.

Bad weather conditions such as torrential rain, heavy snow, and thick fog frequently occur worldwide. Vehicle accidents in such bad weather conditions account for a significant portion of all vehicle accidents, and the level of damage is relatively severe compared to other accidents that occur in clear weather. This paper analyzes the driver's driving stability in bad weather conditions, which has such a significant meaning, in various ways through experiments on the inconvenience experienced by the driver. In this study, three levels of bad weather conditions were implemented in a driving simulator environment to evaluate driver inconvenience for six activities. Through driving experiment, quantitative bio-signals and vehicle signals were analyzed in each weather condition. The SD survey was used to assess the driver's inconvenience level for activities performed while driving and analyze the ranking of inconvenience.

Platoon is a system that connects vehicles through vehicle-to-vehicle (V2V) communication technology to maintain a short distance between vehicles while driving on the road. To improve fuel efficiency, many automotive original equipment manufacturers (OEMs) are interested in developing and demonstrating real-world platoon system. However, it is hard for heavy duty trucks to develop this system due to the difficulty of maintaining the targeted intervehicle distance not only for fuel efficiency but also for safety in case of emergency braking. Because of this critical safety issue in the emergency situation, the platoon system for heavy duty trucks can be hardly demonstrated or tested in real vehicle environment. The relatively complex system and the slow response characteristic of commercial vehicles makes this even more difficult.

A physics-based model for SCR (Selective Catalytic Reduction) was developed based on five independent SGB (Synthetic Gas Bench) tests. There are NH3 adsorption & desorption test, NO oxidation test, NH3 oxidation test, SCR reaction (NOx & NH3) test and SV (Space Velocity) test. To validate the accuracy of SCR model’s prediction, transient reactor tests were conducted at four different input conditions. A newly developed SCR model showed more than 90% prediction accuracy in transient test conditions in view of cumulative NOx. Validation of SCR model was conducted on 1.6L light duty diesel vehicle in the WLTC (Worldwide Harmonized Light vehicles Test Cycle). Based upon this SCR model, vehicle level SCR calibrations used for urea dosing control were made and validated in the emission test cycles like WLTC.

To meet the indoor air quality guideline of newly manufactured vehicles in Korea, China, and other countries, low formaldehyde grade POM (Polyoxymethylene) is used for interior parts essentially. In this paper, formaldehyde scavengers from of 2 commercial low formaldehyde grade POM pellets were identified by LC-MS (Liquid chromatograph-Mass spectrometer) as sebacic dihydrazide and dodecanedioic dihydrazide respectively. The reaction products between formaldehyde and formaldehyde scavengers were also detected, which were converted from hydrazide to hydrazone. So, this kind of additive would be gradually consumed by repetitive molding process or exposure to heat according to formaldehyde emission increase. We are expecting to apply this analytical method and result for quality control and benchmark of low formaldehyde grade POM.

Since the introduction of the DrivAer in 2012 this model has become the standard generic aerodynamic benchmark and aerodynamic research model used by automotive OEMs, software vendors and researchers. In 2017, the relevance of the DrivAer has been furthered by the inclusion of a simplified engine bay. Whilst the DrivAer has become the popular standard, the availability of detailed wind tunnel test data, a key enabler for more sophisticated aerodynamic benchmarking and research, remains limited. This paper presents a comprehensive set of wind tunnel test data of the notchback version of the Ford Open Cooling DrivAer, including aerodynamic force measurements, detailed surface pressure measurements and flow field measurements at 3 cross-sections in the vicinity of the model. In addition, the paper will discuss the sensitivity of the experimental data to wind tunnel repeatability and facility-to-facility variations.

In this study, the preliminary validation method of the steering system is constructed and the objective is to satisfy the target performance in the conceptual design stage for minimizing the problems after the detailed design. The first consideration about steering system is how to extract the reliable steering effort for parking. The tire model commonly used in MBD(Multi-Body Dynamics) has limited ability to represent deformations under heavy loads. Therefore, it is necessary to study adequate tire model to simulate the behavior due to the large deformation and friction between the ground and the tire. The two approaches related with F tire model and mathematical model are used. The second is how to extract each link’s load in the conceptual design stage. Until now, each link’s load could be derived only by actual vehicle test, and a durability analysis was performed using only pre-settled RIG test conditions.

The integration of SCR catalyst into diesel-particulate filter (SDPF) may be one of most viable ways to meet upcoming stringent emission regulations with new test protocols such as Worldwide harmonized Light vehicles Test Cycles (WLTC) and Real Driving Emissions (RDE) requirements. The chabazite-structured SSZ-13-based catalysts enabled the wide implementation of urea-SCR technology for mobile applications due to their robust thermal stability up to 750°C compared to the thermally unstable ZSM-5-based technologies. However, the thermally stable Cu-SSZ-13 catalyst starts losing its initial activity with the increase of aging time at 850°C, where the SCR catalyst on SDPF can possibly be exposed during filter regeneration under a drop-to-idle (DTI) condition. Therefore, more durable SCR catalysts that survive under higher temperatures have been strongly desired in automotive industry. Recently, we found Cu-exchanged high silica LTA revealed an excellent hydrothermal stability.

Generally, vehicles do not need power during deceleration. Therefore, the fuel efficiency can be improved by stopping the fuel injection in this period. However, when the fuel cut is activated, NOx is emitted immediately after fuel cut. During the fuel cut period, a large amount of fresh air flows into the catalytic converter installed on a vehicle since there is no combustion. Thus, the catalytic materials are converted into an oxidizing atmosphere. As a result, NOx purification performance of the catalyst deteriorates, and eventually NOx is emitted when combustion restarts. The quantity of NOx in this period is relatively small. However, in case of increasing fuel cuts, emission problem could arise. Therefore, in order to meet the stringent regulation such as LEV III-SULEV20 or 30, the number of fuel cuts need to be limited. The problem is that this strategy leads to a disadvantage of fuel efficiency.

As a result of stringent global regulations on fuel economy and CO2 emissions, the development of high-efficiency SI engines is more urgent now than ever before. Along with advanced techniques in friction reduction, many researchers endeavor to decrease the B/S (bore-to-stroke) ratio from 1.0 (square) to a certain value, which is expected to reduce the heat loss and enhance the burning rate of SI engines. In this study, the effects of B/S ratios were investigated in aspects of efficiency and knock characteristics using a single-cylinder LIVC (late intake valve closing) GDI (gasoline direct injection) engine. Three B/S ratios (0.68, 0.83 and 1.00) were tested under the same mechanical compression ratio of 12:1 and the same displacement volume of 0.5 L. The head tumble ratio was maintained at the same level to solely investigate the effects of geometrical changes caused by variations in the B/S ratio.

Recently, the design of automotive headlamps has become diversified and complicated according to customer needs. Hence, structural complexity of the headlamps has also increased. Complex structure of the headlamps inevitably causes a disturbance in air circulation. For this reason, inadvertent micro-sized water droplets, called fogging, are condensed on the inner surface of headlamp lens due to temperature difference between the inner and outer lens surfaces. To circumvent fogging inside of the headlamp lens, an anti-fogging coating is indispensable. Conventionally, diverse surfactants have been adopted as substantial material for the anti-fogging coating. However, the usage of the surfactants causes undesirable side effect such as water mark arising from vapor condensation, which is an important issue that must be fully resolved. In this study, we developed an innovative anti-fogging coating material without using conventional surfactant.

The worldwide fuel economy compliance level has been tightening, at the same time, LEV-III/Euro-6d/China-6/BS-6 regulations for NMOG and NOx emissions are being introduced or already effective. Therefore, intensive research effort has been conducted in order to improve the fuel efficiency of passenger cars and reduce exhaust emission. In response to these demands, turbocharged gasoline direct injection (TGDI) engine is being introduced for gasoline vehicles in consideration of fuel efficiency improvement, high output and driving performance compared to naturally aspirated (NA) engine. However, due to its larger thermal mass from the turbo hardware in the exhaust, it suffers from the cold-start emission. The main hazardous gases emitted from gasoline vehicles are CO, HC and NOx, and a three-way catalyst (TWC) is installed for the purification of these harmful emissions.

As environmental problems such as global warming are emerging, regulations on automobile exhaust gas are strengthened and various exhaust gas reduction technologies are being developed in various countries in order to satisfy exhaust emission regulations. Exhaust gas recirculation (EGR) technology is a very effective way to reduce nitrogen oxides (NOx) at high combustion temperatures by using EGR coolers to lower the combustion temperature. This EGR cooler has been mass-produced in stainless steel, but it is expensive and heavy. Recently, high efficiency and compactness are required for the EGR cooler to meet the new emission regulation. If aluminum material is applied to the EGR cooler, heat transfer efficiency and light weight can be improved due to high heat transfer coefficient of aluminum compared to conventional stainless steel, but durability is insufficient. Therefore, the aluminum EGR cooler has been developed to enhance performance and durability.

This paper examines the effect of pulse-and-glide (PnG) driving strategies on the fuel efficiency when applied on parallel HEVs. Several PnG strategies are proposed, and these include the electrical, mechanical, and combined PnG strategies. The electrical PnG strategy denotes the hybrid powertrain control tactics in which the battery is charged or discharged according to the power demanded while maintaining the constant vehicle speed. On the other hand, the mechanical PnG strategy denotes the powertrain control tactics in which the vehicle accelerates or decelerates according to the power load while minimizing the battery usage. The combined PnG strategy involves both electrical and mechanical strategies to find a balanced point in between them. Here, a tradeoff relationship between the fuel efficiency and the vehicle drivability related to the tracking performance of the desired target speed is revealed.

This paper summarizes the validation of prototype vehicle-to-infrastructure (V2I) safety applications based on Dedicated Short Range Communications (DSRC) in the United States under a cooperative agreement between the Crash Avoidance Metrics Partners LLC (CAMP) and the Federal Highway Administration (FHWA). After consideration of a number of V2I safety applications, Red Light Violation Warning (RLVW), Curve Speed Warning (CSW) and Reduced Speed Zone Warning with Lane Closure Warning (RSZW/LC) were developed, validated and demonstrated using seven different vehicles (six passenger vehicles and one Class 8 truck) leveraging DSRC-based messages from a Road Side Unit (RSU). The developed V2I safety applications were validated for more than 20 distinct scenarios and over 100 test runs using both light- and heavy-duty vehicles over a period of seven months. Subsequently, additional on-road testing of CSW on public roads and RSZW/LC in live work zones were conducted in Southeast Michigan.

Improved Lean NOx Trap (LNT) catalysts with enhanced NH3 generation feature were developed for the small diesel engine. The next generation LNT system needs to perform good NOx conversions over the wide temperature range including below 200°C for urban driving and above 400°C for motorway of real road driving. However, the extended use of BaO, a component of LNT known to be very effective for high temperature NOx storage, results in the decrease of low temperature NOx conversion due to the degradation of NO oxidation associating with sulfur over time. The improvement of the low-temperature LNT performance is a key requirement for the real driving emission control as the best operation temperature for urea-SCR is above ~250°C. In this study, our next generation LNT with new washcoat architecture has demonstrated improved NOx removal efficiencies under the wider operation temperature window than the current production technology.

Hyundai's new engine is developed which optimize the cooling efficiency for knocking improvement and friction reduction. The cooling concepts for this purpose are 1) equalizing the temperature among cylinders by flow optimization, 2) cooling the required area intensively, 3) adopting ‘active flow control’ and 4) enlarging fuel economy at high speed range. In order to realize the cooling concept, 1) cross-flow, 2) compact water jacket & exhaust cooling, 3) flow control valve and 4) cylinder head with integrated exhaust manifold are considered. Improvement of knocking and friction reduction by increased cooling water temperature makes fuel efficiency possible. On the other hand, in order to strengthen the cooling around the combustion chamber and to reduce the deviation among the combustion chamber of cylinders, it is required to design the head water jacket shape accordingly.