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The weight reduction and noise refinement of powertrain has been major concern in automotive industry although they are known as self trade-off. This paper presents various methods to deal with those problems for new Hyundai 1.5 liter powertrain. It was possible to reduce the weight of powertrain by using plastic for both headcover and intake manifold, aluminum for crankshaft damper pulley and stainless steel for exhaust manifold and by reducing the general thickness of cylinder block On the other hand, the noise refinement of vibration in the powertrain was made by optimizing the engine structure and by adapting the hydraulic lash adjuster valve train system, which was proved to be effective in mechanical noise of engine.

Currently, diesel engine-out exhaust NOx emission level prediction is a major challenge for complying with the stricter emission legislation and for control purpose of the after-treatment system. Most of the NOx prediction research is based on the Zeldovich thermal mechanism, which is reasonable from the physical point of view and for its simplicity. Nevertheless, there are some predictable range limitations, such as low temperature with high EGR rate operating conditions or high temperature with low EGR rates. In the present paper, 3 additional considerations, pilot burned gas mixing before the main injection; major NO formation area; concentration correction, were applied to the previously developed real-time NO estimation model based on in-cylinder pressure and data available from ECU. The model improvement was verified on a 1.6 liter EURO5 diesel engine in both steady and transient operation.

The worldwide automotive industry is currently preparing for a market introduction of hydrogen-fueled powertrains. These powertrains in fuel cell electric vehicles (FCEVs) offer many advantages: high efficiency, zero tailpipe emissions, reduced greenhouse gas footprint, and use of domestic and renewable energy sources. To realize these benefits, hydrogen vehicles must be competitive with conventional vehicles with regards to fueling time and vehicle range. A key to maximizing the vehicle's driving range is to ensure that the fueling process achieves a complete fill to the rated Compressed Hydrogen Storage System (CHSS) capacity. An optimal process will safely transfer the maximum amount of hydrogen to the vehicle in the shortest amount of time, while staying within the prescribed pressure, temperature, and density limits. The SAE J2601 light duty vehicle fueling standard has been developed to meet these performance objectives under all practical conditions.

Emission of carbon dioxide from mobile sources seriously concerned to solve greenhouse effect and high price of gasoline in some countries have resulted in the development of lean-burn concept engine. In spite of many studies on the lean deNOx catalyst, we have no clear solution to obtain high fuel economy and high efficiency of NOx conversion in lean-burn application. This paper describes applicability and problems of NOx adsorber system to partial lean-burn vehicle, the development of three-way catalyst with improvement of washcoat technology based on three-way catalyst used for gasoline application, and comparison test results of evaluations is synthesized gas activity test, Federal Test Procedure (FTP) test, etc. This study shows improved three-way catalysts in partial lean- burn vehicle have max. 89% of NOx conversion in FTP without adding rich spike and regeneration functions to engine management system.

There have been strong moves in recent years to introduce the metal matrix composites concept into higher volume applications, notably the automotive field where large volume production and lower material costs are required. The wettability between reinforcing materials and base material is one of important factors for the strength of composites and its manufacture. The main objective of this paper is to establish a basic understanding of wetting phenomena in SiC/liquid aluminum and aluminum alloy systems. In the present paper, results from the sessile drop method are reported for the effects on the wetting angle, θ, of free silicon in the silicon carbide substrate and of alloying additions of silicon, copper or magnesium to the aluminum drop for the temperature range 700-900 or 1400°C in the titanium-gettered vacuum (1.3 x 10-2 / 1.3 x 10-3 Pa).

The purpose of this paper is to closely examine the influence of the behavior of fuel mixture in the intake manifold on combustion characteristics, performances of engine output and exhaust emission by using a 4-stroke spark ignition engine. In case of removing the liquid film fuel flowing on the wall of the intake manifold and of not removing it, the values of combustion characteristics such as the heat release delay, the combustion delay, the rate of heat release, the burned mass fraction and the maximum combustion pressure were obtained from the analysis of pressure indicator diagram. And then, the values of engine performance and concentration of exhaust gas were obtained.

Main design features and some of the development work carried out on the first new engines to be produced in-house by Hyundai Motor Co. are described. The Alpha family of multi-valve, four cylinder engines comprises 1.3 and 1.5L naturally aspirated units and a 1.5L turbocharged version. Modern features are incorporated in the engines in order to provide higher performance and good fuel economy with excellent durability at reasonable cost. Hyundai Motor Co. (HMC) was established in 1967 and, in the following year, commenced production of passenger cars for the domestic market, using CKD components supplied by Ford of Europe. In 1974 the Pony saloon car entered production; this used mainly locally produced components but most of the major items, including the power train - engine and gearbox - were manufactured under the license from Mitsubishi Motors.

In order to investigate the characteristics of top ring groove deposit formation in gasoline and diesel engine, engine test and simulation test were performed. From component analysis of used oils sampled from actual running engines, oxidation and nitration for gasoline engine and soot content for diesel engine were selected as main parameters for evaluating oil degradation. In gasoline engine, deposit formation increases linearly with oxidation and nitration, and especially, oil oxidation is a dominant factor on the deposit formation rather than nitration. And, deposit formation increases gradually in low temperature ranges below 260°C even if oils are highly oxidized, but it increases rapidly if piston top ring groove temperature is above 260°C. In diesel engine, deposit formation is highly related to soot content in lubricating oils.

As CO2 legislation tightens, the next generation of turbocharged gasoline engines must meet stricter emissions targets combined with increased fuel efficiency standards. Recent studies have shown that the following technologies offer significant improvements to the efficiency of turbocharged GDI engines: Miller Cycle via late intake valve closing (LIVC), low pressure loop cooled EGR (LPL EGR), port water injection (PWI), and cylinder deactivation (CDA). While these efficiency-improving technologies are individually well-understood, in this study we directly compare these technologies to each other on the same engine at a range of operating conditions and over a range of compression ratios (CR). The technologies tested are applied to a boosted and direct injected (DI) gasoline engine and evaluated both individually and combined.

As CO2 legislation tightens, the next generation of turbocharged gasoline engines must meet stricter emissions targets combined with increased fuel efficiency standards. Promising technologies under consideration are: Miller Cycle via late intake valve closing (LIVC), low pressure loop cooled exhaust gas recirculation (LPL EGR), port water injection (PWI), and cylinder deactivation (CDA). While these efficiency improving options are well-understood individually, in this study we directly compare them to each other on the same engine at a range of operating conditions and over a range of compression ratios (CR). For this purpose we undertake a comprehensive simulation of the above technology options using a GT-Power model of the engine with a kinetics based knock combustion sub-model to optimize the fuel efficiency, taking into account the total in-cylinder dilution effects, due to internal and external EGR, on the combustion.

This paper describes how to meet LEVII ULEV70 emission standards and minimize fuel consumption with the combined NOx after-treatment (LNT+SCR) system for diesel vehicles. Through analysis of LNT's functionality and characteristics in a LNT+SCR combined after-treatment system, allowed a new control strategy to be established, different from the existing LNT-only system. In the 200°C or higher condition where SCR can provide the most stable NOx conversion efficiency, rich regeneration of LNT was optimized to minimize LNT deterioration and fuel consumption. Optimized mapping between rapid heat up strategy and raw NOx reduction maximized LNT's NOx conversion efficiency during the intervals when it is not possible for SCR to purify NOx This study used bench aged catalysts which were equivalent to 150K full useful life.

This study suggests new types of catalysts that show low hydrogen sulfide emission without scavenger such as NiO. Hydrogen sulfide can be reduced by changing the physicochemical properties of washcoat components. Synthesized gas activity tests were performed to investigate the effect of modified washcoat on hydrogen sulfide formation and catalytic activity. BET surface area tests, X- ray diffraction tests, and gas chromatography tests were also carried out to examine the characteristics of catalysts. Preparation methods for catalysts were focused on minimizing the adsorption of sulfur species on catalysts. The first approach is heat treatment of cerium oxide to reduce adsorption sites for sulfur compounds. But this leads to deterioration of CO and NOx conversion efficiencies. The second one is adding new types of promoters that increase thermal durability and dynamic oxygen storing function of cerium oxide.

This paper describes Hyundai's research and development work on a flexible fuel vehicle (FFV). The work on FFV has been conducted to evaluate its potential as an alternative to the conventional gasoline vehicle. Hyundai FFV described here can operate on M85, gasoline, or any of their combinations, in which the methanol concentration is measured by an electrostatic type fuel sensor. For that operation, a special FFV ECU has been developed and incorporated in the FFV. The characteristics affecting FFV operation, such as FFV ECU control strategy and injector flow rate, have been investigated and optimized by experiment. Various development tests have been performed in view of engine performance, durability, cold startability, and exhaust emissions reduction. The exhaust gas aftertreatment system being consisted of manifold type catalytic converter(MCC) and secondary air injection system has shown good emission reduction performance including formaldehyde emission.

In recent years, emission regulations have been getting increasingly strict. In the development of engines that comply with these regulations, in-cylinder pressure plays a fundamental role, as it is necessary to analyze combustion characteristics and control combustion-related parameters. The analysis of in-cylinder pressure data enables the modelling of exhaust emissions in which characteristic temperature can be derived from the in-cylinder pressure, and the pressure can be used for other investigations, such as optimizing efficiency and emissions through controlling combustion. Therefore, a piezoelectric pressure sensor to measure in-cylinder pressure is an essential element in the engine research field. However, it is difficult to practice the installation of this pressure sensor on all engines and on-road vehicles owing to cost issues.

Recently, flexible fuel vehicle (FFV) has been drawn great attention because of its response for immediate use as alternative fueled one. Hyundai FFV can be operated on arbitrary fuel mixtures between gasoline and M85 with the specially programmed electronic control unit (ECU) which can determine optimized fueling quantity and ignition timing as the methanol content by the signal from electrostatic type fuel sensor. In this paper, the results of various tests including engine performance, cold startability, durability and exhaust emission reduction have been described. Full load, cold mode durability tests and field trials have been carried out with some material changes and surface treatments in the lubricating parts and fuel system. But, more work on its durability improvement is still required.

A preconverter is an essential component of the new vehicle exhaust system for the achievement of tightened emission standards. To meet those standards, the Manifold Catalytic Converter (MCC) system has been developed in the Hyundai Motor Company (HMC). Unfortunately, the conventional MCC is no longer a suitable design for the exhaust gas treatment of the newly developed high performance engine since it cannot withstand the engine's exhaust temperature, vibration, pressure pulsation, and many other severe conditions. This paper is focused on a failure-mode analysis and new packing designs for the MCC application through a series of durability tests.

It is well known that the EHC (Electrically Heated Catalyst) is very effective for the reduction of cold-start hydrocarbon emissions. To optimize EHC applications for LEVI (Low Emission Vehicle) and ULEV (Ultra Low Emission Vehicle) standards, the effect of heating and secondary air injection on the emission purification efficiency in FTP (Federal Test Procedure) were evaluated with three different EHC system configurations. The exhaust manifold location EHC system in which the EHC with a light-off catalyst is installed near the exhaust manifold, yields 0.038g/mile of THC (Total Hydrocarbon emissions) when the test was performed according to the FFP with an engine-aged condition equivalent to 50,000miles. Therefore, the ULEV standards could be achieved through the system. A new battery system for the EHC and a single battery system for vehicle application were evaluated. Evaluation of the Ni-MH battery for EHC system is included.

In order to extend the operability limit of the gasoline compression ignition (GCI) engine, as an avenue for low temperature combustion (LTC) regime, the effects of parametric variations of engine operating conditions on the performance of six-stroke GCI (6S-GCI) engine cycle are numerically investigated, using an in-house 3D CFD code coupled with high-fidelity physical sub-models along with the Chemkin library. The combustion and emissions were calculated using a skeletal chemical kinetics mechanism for a 14-component gasoline surrogate fuel. Authors’ previous study highlighted the effects of the variation of injection timing and split ratio on the overall performance of 6S-GCI engine and the unique mixing-controlled burning mode of the charge mixtures during the two additional strokes. As a continuing effort, the present study details the parametric studies of initial gas temperature, boost pressure, fuel injection pressure, compression ratio, and EGR ratio.

In order to achieve the proper automobile interior sound, the tailpipe noise of the exhaust system must be considered as a main contributor. This paper describes a study of the achievement of dynamic sound quality through exhaust system design. Firstly, we determined the vehicle's interior sound quality and established a target sound using a subjective assessment of 10 benchmark vehicles. The exhaust noise target is determined by means of transfer path analysis focusing on the noise source and how it's impacted by the muffler design. The exhaust system is commonly modeled as a combination of source strength and impedance. We obtained the source character by the wave decomposition method using two microphones and six loads ultimately leading to an optimized design of the inner muffler structure. Based on this study, we achieved dynamic interior sound and improved exhaust system performance.

To meet Euro6 regulation particulate matter MEMS sensor is suggested. This sensor detects induced charges by PM. To increase sensitivity of the sensor, surface area of the sensor is increased by MEMS process. Sensor is made by low resistive silicon. Total size is 4.3 mm x 59.4 mm x 1 mm and size of sensor part is 4.3 mm x 13 mm. On the backside of the sensor, Pt heater is fabricated to remove piled PM on sensor part. After sensor part, charge amplifier is used to measure the induced charge of the sensor. From FFT of sensor signal, it can sense 5.46 mg/m₃ of PM. In this paper, MEMS devices for exhaust system monitoring of automobiles are investigated. PM emitted from diesel engine is charged particle. Charge-induced-type PM sensor we designed can measure by real time and it doesn't need particle collection apparatus