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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.

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.

The switching on/off system, which is one of the means to control the semi-active damper, is utilized with the merit of its simple control method but the shock force occuring in the mode change is still a problem to be overcome in this kind of damper. In this study, by simulating a quarter car model which incorporates the damper mass and the stiffness of damper mount bushes, the presence of the shock force and the characteristic of the shock force was examined. This study suggests an interesting relationship between the frequency of the shock force induced in the damper mode change and the stiffness of the damper mount bushes.

The theory and the computer software to analyze the behaviour of moving mechanism(Hood, Tail Gate and Trunk Lid) equiped with the gas lifters or the torsion bars has been developed to figure out what will be the dynamic behaviour of moving mechanism at the design stage. The developed computer software gives the approximated calculation of load-angle characteristics, the velocity, the acceleration and the total opening time so that the designer makes the optimum decision on the location and the strength of panel to which the gas lifters or the torsion bars are mounted.

In HMC, the fundamental research on the hydrogen fueled engine and vehicle has been carried out. For this engine, solenoid driven injector is used to supply gaseous hydrogen into the cylinder and various operating parameters have been changed to study the combustion characteristics of hydrogen. After these experiments on engine, hydrogen fueled vehicle has been constructed and it is controlled by ECU. The amount of emission from the hydrogen vehicle with stoichiometric operation is less than 1/3 of the ULEV legislation.

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.

A computational technique for predicting roof crush resistance in the early design stage of vehicle development is presented in this paper. This technique developed a simple nonlinear finite element beam model with several nonlinear spring elements which represent plastic hinge behaviors after bending collapse. In general, these plastic hinge behaviors are apt to occur al each weak area of vehicle body structure. By idealizing actual sections as equivalent simple sections, maximum bending moments are calculated for all weak areas. Predicted results of roof crush resistance arc correlated well with test results.

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.

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

A new exhaust system has been developed to cope with post-SULEV (Super Ultra-Low Emissions Vehicle) regulation by newly designed hardware of exhaust system. This paper will describe the various new technologies used for achieving the post-SULEV standards, such as Conicat (cone-type metal catalyst), dual-wall pipe, pipe-type metal catalyst, ultra thin wall monolith and HC trap system for the improvement of catalyst light-off time. The tested data on 2.0L SULEV vehicle indicate that Conicat(cone-type metal catalyst) and HC trap (hydrocarbon absorbing catalyst) have more positive characteristics, and are expected to show the enhanced HC reduction performance with the optimization of emission system.

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.

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.

As electric vehicles become more widespread, such vehicles may be subject to “range anxiety” due to the risk of discharging during driving or the discharging when left unused for a long period. Accordingly, a vehicle equipped with a mobile charger that can provide a charge in an emergency. The vehicle with the mobile charger is usually composed of a large capacity battery, a power converter in a small truck. However, the large capacity battery and the power converter are disadvantageous in that they are large in size and expensive and should be produced as a special vehicle. In this paper, we propose a method to solve the problem using an internal EV system without requiring an additional power generation, battery and a charging-and-discharging device. The method is a novel Vehicle-to-Vehicle (V2V) fast charging control system utilizing motor and inverter in EV.

In case of all gasoline vehicles such as the passenger vehicle, heavy duty truck and light duty truck etc., a fuel pump is located inside the fuel tank and transfers the fuel to an engine for stable driving, however, engine stall can be occurred by low pressure fuel pump. The boiling temperature of gasoline fuel is very low, the initial boiling point is around 40°C so fuel can boil easily while driving and end boiling point is around 190°C. It boils sequentially depending on the temperature. It becomes the criteria to determine the amount of vapor released inside the fuel tank at high temperature. The main cause of engine stall at high temperature is rapid fuel boiling by increasing fuel temperature. This causes a lot of vapor. Such vapor flows into the fuel pump which leading to decrease the pump load and the current consumption of the fuel pump continuously. This ultimately results in engine stall.

Vehicle suspensions can be regarded as interconnection of rigid bodies with kinematic joints and compliance elements such as springs, bushings, and stabilizers. Design of a suspension system requires detailed specification of the interconnection point (or so called hard points) and characteristic values of compliance elements. During the design process, these design variables are determined to meet some prescribed performance targets expressed in terms of SDFs(Suspension Design Factors), such as toe, camber, compliance steer, etc. This paper elaborates on a systematic approach to achieve optimum design of suspension systems.

The shape of unit cell of catalytic converter has great influence on the conversion efficiency and pressure drop characteristics. Therefore, the properties of design parameters of catalyst monolith were analyzed and the parameters of various cell shapes of catalyst were compared. Also, the numerical study of a three dimensional compressible flow in a Close-coupled Catalyst Converter (CCC) system was performed to investigate the flow characteristics and the flow distribution of exhaust gases. Unsteady flow analysis shows that severe interferences of each pulsating exhaust gas flow as well as geometric factors (junction, mixing pipe, cell shape etc.) influence greatly on the flow uniformity and flow characteristic in substrate. The results can be applied for the catalytic converter design.

This paper presents a study on using rubber bushing as a sensor for the identification of forces transmitted onto the car body. The method starts from the idea that the transmission forces can be related to the deformation of the rubber bushing multiplied by its stiffness. Deformation of the rubber bushing is estimated from relative vibrations across the bushing. Simple theories are presented to deal with modeling of the rubber bushing and processing of the vibration mesurements on the link and car body to identify the transmission forces. Then, validity of the proposed approach is shown by applications to a suspension system under several driving conditions.

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.

Polylactide (PLA), which is one of the most important biocompatible polyesters that are derived from annually renewable biomass such as corn and sugar beets, has attracted much attention for automotive parts application. The manufacturing method of PLA is the ring-opening polymerization of the dimeric cyclic ester of lactic acid, lactide. For the PLA composites including stereocomplexed with L- and D-PLA, we developed the unit processes such as fermentation, separation, lactide conversion, and polymerization. We investigated D-lactic acid fermentation with a view to obtaining the strains capable of producing D-lactic acid, and through catalyst screening test for polycondensation and depolymerization reactions, we got a new method which shortens the whole reaction time of lactide synthesis step. Poly(d-lactide) is obtained from the ring-opening polymerization of d-lactide. Also we investigated several catalysts and polymerization conditions.