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During the vehicle lifecycle, customers are able to directly perceive the outer panel stiffness of vehicles in various environmental conditions. The outer panel stiffness is an important factor for customers to perceive the robustness of the vehicle. In the real test of outer panel stiffness after prototype production, evaluators manually press the outer panel in advance to identify vulnerable areas to be tested and evaluate the performance only in those area. However, when developing the outer panel stiffness performance using FEA (Finite Element Analysis) before releasing the drawing, it is not possible to filter out these areas, so the entire outer panel must be evaluated. This requires a significant amount of computing resources and manpower. In this study, an approach utilizing artificial intelligence was proposed to streamline the outer panel stiffness analysis and improve development reliability.

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.

For making metal touch feeling and lighting simultaneously, selective electroplating is widely applied in button, panel and etc. in interior/exterior parts of automotive. In this paper, new selective electroplating with printing are suggested as an alternative manufacturing process of two shot molding, PC (Polycarbonate) and ABS (Acrylonitrile-Butadiene-Styrene). Manufacturing process of selective electroplating with printing is as follows: For preventing to plate metal layer in area of letter or symbol, masking ink is printed on parts, button, panel, etc., with electroplatable PC+ABS. After conventional electroplating process, the part has electroplated metal layer except for the printed area. It had been studied the composition of ink and PC+ABS for obtaining skip plating and light transmittance on printed area.

A signal lamp performs a function to inform the position and behavior of the vehicle. And it represents a specific design identity of the vehicle or brand identity. Recently it implements the unique three-dimensional effect while using a LED. However, a number of LEDs and complex form of the lens shape have to be applied, so results in the size, weight, cost increase. In this study, the hologram technology that is an exemplary technique for implementing the described three-dimensional image is applied. With a hologram, it is possible to reproduce a complex shape three-dimensional image by using a hologram film. Therefore the number of parts can be reduced. And it is possible to copy the film has a mass production benefits.

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.

Automotive companies are trying to enhance the customer’s impression by improving engine sound quality. The target of this sound quality is to create a brand sound that is preferred by their customers as well as quietness of interior noise. Over the past decade there have been many studies in the field of automotive sound quality. These have included the technologies such as tuning of intake orifice and exhaust orifice, tuning of structure-borne, intake feedback devices, active exhaust valves, ANC (Active Noise Cancellation) and ASD (Active Sound Design). The three elements of the sound that affect the feeling of the customer are known as engine order arrangement, frequency balance, and linearity. Here, the most important thing in sound quality development is the order arrangement.

In recent years, the emerging technology competitions in automotive industry are improving engine efficiency and electronizing for coping with stringent fuel-economy regulations. However, fuel-economy technologies such as engine down-sizing and numerous electronic parts entrust burden plastic materials acing as mainly electric insulation and housing to have to be higher performance, especially temperature endurance. Engineering plastics (EPs) have critical limitations in terms of degradation by heat. Heat-resisting additives in EP are generally used to be anti-degradation as activating non-radical decomposition of peroxide. However, it could not be effective way to impede the degradation in long term heat aging over 1,000 hours at high temperature above 180 °C. In this study, we suggested the new solution called ‘shield effect’ that is purposeful oxidation at the surface and local crystallization of EP to stop prevent penetrating oxygen to inside of that.

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.

Impact resistance of plastic underbody parts was studied using simulated injection-molded specimen which can be tested according to different types of material used, injection molding variants like position and number of injection molding gates, and features of ribs. Material applied was glass fiber reinforced polyamide which can be used in underbody parts. Test was performed using several combinations of injection molding gates and rib types. From the test result, optimal design guide for plastic underbody parts was determined. Also, new high impact resistant plastic material made of glass fiber reinforced polyamide 66 (PA66) and polyamide 6 (PA6) alloy was developed and the material properties useful for CAE were determined. As a case study, oil pan and muffler housing were designed following the optimal design guide and CAE. And the reliability of the sample muffler housing designed was verified.

This study has been conducted to analyze microbial diversity and its community by using a method of NGS(Next generation sequencing) technique that is not rely on cultivation for microbial community in an core evaporator causing odor of car air conditioner. The NGS without any cultivation method of cultivation, has been developed recently and widely. This method is able to research a microorganism that has not been cultivated. Differently with others, it can get a result that is closer to fact, also can acquire more base sequence with larger volume in relatively shorter time. According to bacteria population analysis of 23 samples, It can be known limited number of bacteria can inhabit in Evaporator core, due to small exposure between bacteria and evaporate, as well as its environmental characteristics. With the population analysis, only certain group of it is forming biofilm in proportion.

In order to reduce the cost and weight of the soft-foamed instrument-panel (IP), we developed the new IP which is made by the 2 kinds of injection methods. One is the compression-injection with back-foamed foil inserted, and the other is two-shot injection with the passenger-side airbag (PAB) door. We named it ‘IMX-IP’ which means that all components (‘X’) of the IP with different resins are made In a Mold. The development procedure of this technology was introduced (1) Design of the new injection mold through TRIZ application, (2) Optimization of the injection conditions and back foamed-foil for minimizing the foam loss and thickness deviation, (3) Development of CAE method for two-shot injection compression, (4) Reliability performance test and application to the mass production. The reduction of the processes through the two-shot molding with back foamed-foil inserted made it possible to enhance soft feeling on IP and reduce the cost and weight simultaneously.

The focus of this paper is to develop an innovative vehicle layout and optimize vehicle body structure with the latest lightweight steel technologies, such as hydro-forming and hot stamping. Our BIW structure achieved a mass savings of 28 kg (−10%) compared to the mass of baseline BIW structure. (Base BIW : MD_Elantra)

In diesel engine development, the new technology is coming out to meet the stringent exhaust emission regulation. The regulation demands more eco-friendly vehicles. Euro6c demands to meet not only WLTP mode, but also RDE(Real Driving Emission). In order to satisfy RDE mode, the new technology to reduce emissions should cover all operating areas including High Load & High Speed. It is a big challenge to reduce NOx on the RDE mode and a lot of DeNOx technologies are being developed. So the new DeNOx technology is needed to cover widened operating area and strict acceleration / deacceleration. The existing LNT(Lean NOx Trap) and Urea SCR(Selective Catalytic Reduction) is necessary to meet the typical NEDC or WLTP, but the RDE mode demands the powerful DeNOx technology. Therefore, the LNT & Urea SCR on DPF was developed through this study.

SUS exhaust manifold is weaker than cast iron in aspect of high temperature vibration. So as to improve reliability of SUS exhaust manifold and get over gas temperature limit, exhaust manifold vibration mode and level has to be decreased. And because of error and limit of conventional modal analysis, we measured vibration mode and level of SUS exhaust manifold directly in engine firing condition. To measure vibration of hot parts(600∼800°C) in engine, we used special cooling device at base of accelerometer. Thus we developed analysis method of SUS exhaust manifold crack mechanism. We came to know the accurate vibration mode and level of SUS exhaust manifold in hot condition. Besides, we found out in proportion as vibration level increases endurance life decreases.

Systematic numerical simulations were performed for the improvement of fuel efficiency and thermal performance of a compact size passenger vehicle. Both aerodynamic and thermal aspects were considered concurrently. For the sake of systematic evaluation, our study was conducted employing various design changes in multiple steps: 1) analysis of the baseline design; 2) elimination of the engine room components; 3) modification of the engine room component layout; 4) modification of the aerodynamic components (such as under body cover and cooling ducts). The vehicle performance characteristics corresponding to different design options were analyzed in terms of aerodynamic coefficient, engine coolant temperature, and surface temperatures of thermally critical components such as battery and exhaust manifold. Finally optimal design modification solutions for better vehicle performance were proposed.

Diesel engines are the most commonly used power train of the freight and public transportations in the world. From the viewpoint of global warming restraint, however, reduction of exhaust emissions from the diesel engine is urgent demand. Stringent emission regulations are being proposed with growing concern on NOx, PM and CO2 emissions. Future emission regulations require advanced emission control technologies, such as SCR(Selective Catalytic Reduction), LNT(Lean NOx Trap) and EGR(Exhaust Gas Recirculation). The EGR is a commonly used technique to reduce emission. In this study, a LP-EGR(Low Pressure Exhaust Gas Recirculation) system was investigated to evaluate its potential on emission reduction and fuel economy improvement, especially for a passenger diesel engine. A 3.0ℓ diesel engine equipped with the LP-EGR system was tested using an in-house control algorithm.

As the use of diesel engines increases in the transportation industry and emission regulations tighten, the implementation of diesel particulate filter systems has expanded. There are many challenges associated with the design and development of these systems. Some of the key robustness parameters include regeneration, efficiency, fuel penalty, engine performance, and durability. One component of durability in a diesel particulate filter (DPF) system is the filter's ability to resist ring-off-cracking (ROC). ROC is described as a crack caused primarily by thermal gradients, differentials, and the resulting stresses within the DPF that exceed its internal strength. These cracks usually run perpendicular to the substrate flow axis and typically result in the breaking of the substrate into separate halves.

For optimizing the performance of SI engine such as engine torque, fuel consumption, and emissions, various types of system for variable valve timing were developed by many automotive researchers. In this paper, we investigated the relationship between valve timing and intake orifice noise, and suggested how to improve NVH (Noise, Vibration and Harshness) performance as well as engine torque. Some experiments using the engine dynamometer were carried over about 150 different operating conditions. BEM analysis was also conducted in order to calculate acoustic modes of intake system. The results show that the valve timing and overlap of breathing systems have influence on NVH behavior, especially intake orifice noise over whole range of operating conditions. Valve timing and overlap of intake and exhaust valve were optimized in the view of sound quality as well as overall noise level.