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The study of oil emission is of essential interest for the engine development of modern cars, as well as for the understanding of hydrocarbon emissions especially during cold start conditions. A laser mass spectrometer has been used to measure single aromatic hydrocarbons in unconditioned exhaust gas of a H2-fueled engine at stationary and transient motor operation. These compounds represent unburned oil constituents. The measurements were accompanied by FID and GC-FID measurements of hydrocarbons which represent the burned oil constituents. The total oil consumption has been determined by measuring the oil sampled by freezing and weighing. It has been concluded that only 10 % of the oil consumption via exhaust gas has burned in the cylinders. A correlation of the emission of single oil-based components at ppb level detected with the laser mass spectrometer to the total motor oil emission has been found.

External Exhaust Gas Recirculation (EGR) provides an opportunity to increase the efficiency of turbocharged spark-ignition engines. Of the competing technologies and configurations, Low-Pressure EGR (LP-EGR) is the most challenging in terms of its dynamic behavior. Only some of the stationary feasible potential can be used during dynamic engine operation. To guarantee fuel consumption-optimized engine operation with no instabilities, a load point-dependent limitation of the EGR rate or alternatively an adaptation of the operating point to the actual EGR rate is crucial. For this purpose, a precise knowledge of efficiency and combustion variance is necessary. Since the operating state includes the actual EGR rate, it has an additional dimension, which usually results in an immense measuring effort.

It is necessary for vehicle horns not only to satisfy regulations on the sound level but also to fulfill various demands related with sound quality. For example, a disk type horn which is attached on most of small size vehicles has been required to improve its sharp feeling sound. However, the improvement of horn sound has been deterred mainly due to the deficiency of the understanding on how design factors are related with emotional judgments on horn sound. In addition, a proper CAE tool is not available in the process of horn design since it is difficult to describe multi-physical phenomena engaged with horns. The purpose of this study is to improve the sound quality of a disk type horn. In order to achieve this goal, firstly, acoustic characteristics of horns were obtained through a series of experiments. In addition, various sound quality metrics were examined in order to derive design factors affecting sound quality enhancement.

In diesel engine development, fuel consumption, emissions and combustion noise have been main development objectives for fuel economy, low emissions and NVH. These main objectives can be achieved with advanced engine technologies. As electronic actuating systems are widely applied on diesel engines, elaborate control is required. This is because the main development targets are greatly affected by engine control parameters but frequently have a trade-off relationship. Therefore, the optimization of combustion control parameters is one of the most challenging tasks for improvement. As an efficient method, the DOE methodology has been used in engine calibration. In order to develop a mathematical model, the input and output values must be measured. Unlike other variables, combustion noise has been continually reported to have better indication method in simplified way. In this paper, advanced noise index from cylinder pressure signal is applied on engine test.

This paper focuses on the vehicle test result of the US fuel economy test cycles such as FTP75, HWY and US06 with model based Cooled EGR system. Cooled EGR SW function was realized by Model Based Development (internal rapid prototyping) using iRPT tool. With EGR, mixing exhaust gas with clean air reduces the oxygen concentration in the cylinder charge, as a result, the combustion process is slowed, and the combustion temperature drops. This experiment confirmed that the spark timing was more advanced without knocking and manifold pressure was increased in all cases with EGR. A positive potential of fuel economy improvement on FTP mode, US06 mode have seen in this experiment but not for HWY where the engine load is quite low and the spark advance is already optimized. As a result, fuel economy was increased by maximum 3.3% on FTP, 2.7% on US06, decreased by 0.3% on HWY mode respectively with EGR.

This paper provides a method that corrects errors induced by the empty-tunnel pressure distribution in the aerodynamic forces and moments measured on an automobile in a wind tunnel. The errors are a result of wake distortion caused by the gradient in pressure over the wake. The method is applicable to open-jet and closed-wall wind tunnels. However, the primary focus is on the open tunnel because its short test-section length commonly results in this wake interference. The work is a continuation of a previous paper [4] that treated drag only at zero yaw angle. The current paper extends the correction to the remaining forces, moments and model surface pressures at all yaw angles. It is shown that the use of a second measurement in the wind tunnel, made with a perturbed pressure distribution, provides sufficient information for an accurate correction. The perturbation in pressure distribution can be achieved by extending flaps into the collector flow.

The new concept oxidation for diesel engine has been developed. It has been designed to use under circumstances of the "dry condition" of exhausted emission, which indicates low soluble organics and high dry soot concentration under high exhaust gas temperature. For the reliability and performance of catalysts in dry condition, several design concepts were established. First of all, extremely low sulfate formation on catalyst at high temperature conditions, and an improved soluble organic burning characteristics was required. A minimization of deposition of the particulate component, especially sulfate, was obtained from the adjustment of washcoat loading and material property. Six different types of catalysts have been prepared and tested in a laboratory. Diesel vehicle test showed the possibility that soluble organic could be removed mostly with minimal sulfate formation.

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.

In order to improve the fuel consumption ratio of the vehicle, a great deal of research is being carried out to improve air-conditioning efficiency. Increasing the efficiency of the condenser is directly connected to the power consumption of the compressor. This paper describes an experimental method of using an additional water-cooled condenser to reduce power consumption and decrease discharge pressure of the air-conditioning system. First, the principle of a combined cooling (water + air) method was evaluated theoretically. Next, experimental proof was conducted with the additional water-cooled condenser. The shape and structure is similar to the plate type of the transmission oil cooler used in a radiator. Through a number of tests, it was found that it is possible is to reduce power consumption of compressor by decreasing discharge pressure.

As CO2 emissions from vehicles is gaining a global attention the low fuel consuming power-train is in much greater demand than before. Some alternatives are suggested but the HSDI diesel engine would be the most realistic solution. Vehicle simulation shows that low fuel consuming car can be realized by applying 1∼1.2L HSDI diesel engine in vehicles weighing about 750kg. While the direct injection diesel engine has been researched for a long time enhancement of mixing between air and fuel in a limited space makes it challenging area to develop a small swept volume HSDI diesel engine. We are investigating small HSDI diesel engine combustion technologies as an effort to realize low fuel consuming vehicle. Our main objective in this study is to have a better understanding of the combustion related parameters from such a small size HSDI diesel engine in order to improve engine performance.

How can car manufacturers, which are primary mechanical engineers, become software specialists? This is a question of prime importance for car electronics in the future. Modern vehicles offer a large number of electronic and software based functions to achieve a high level of safety, fuel economy, comfort, entertainment and security which are developed under pressure of regulations, of consumers needs and of competitive time to market aspects. This contribution draws a picture, what could be important in future for in car communication and information system in terms of development process, HW & SW architectures, partnerships in automotive industry and security of industrial properties. For this purpose the automotive development is reviewed and actual examples of system designs are given.

Recently weight reduction is increasingly needed in automotive industry to improve fuel efficiency and to meet a CO2 emission requirement. In this paper, we prepared composite body panels for the lightweight vehicle based on a small passenger car. Fender, roof, door, side outer panel, and tailgate are made from hand layup using a glass/carbon hybrid reinforcement. Hood is made from low pressure sheet molding compound (SMC) to investigate feasibility of mass production. Both hand layup and low pressure SMC materials are newly developed and their physical properties are examined. CAE simulation was done for strength analysis and optimization of thickness for the body panels.

A technical approach to reduce NOx and to minimize the fuel consumption caused by the DeNOx aftertreatment system was introduced. The NEDC mode test of the HMC (Hyundai Motor Company) DeNOx system was done with a Euro 5 vehicle (ETW (Equivalent Test Weight) = 1,810 kg, 143 kW, 430 N⋅m), which resulted in that the Euro 6 legislation standards were met. The NOx and HC emissions were, respectively, measured to be 0.059 g/km and 0.087 g/km with the hydrothermal-aged catalysts, and CO₂ was increased by ≺ 4%.

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.

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.

Urea-SCR system consisted of combined deNOx catalysts with wide range of temperature window, injector, sensor and injection controller. Synthetic gas activity test and NOx conversion efficiency test on the engine bench were carried out to evaluate and improve the performance of this system. To better suit the application of the urea-SCR system without engine modification, temperature of catalyst and engine RPM were used as input data to control amounts of urea aqueous solution that reacts with NOx. We concentrated on designing types of deNOx catalysts and controlling amounts of urea solution under different driving conditions to achieve higher NOx reduction and wider temperature window. Designed urea-SCR system showed substantial NOx reduction performance and relatively wide temperature window under different driving conditions.

Development of eco-friendly vehicles have risen in importance due to fossil fuel depletion and the strengthened globalized emission control regulatory requirements. A lot of automotive companies have already developed and launched various types of eco-friendly vehicles which include hybrid vehicles (HEVs) or electric vehicles (EVs) to reduce fuel consumption. To maximize fuel economy Hyundai-Kia Motor Company has introduced eco-friendly vehicles which have downsized or eliminated vibration damping components such as a torque converter. Comparing with Internal Combustion Engine(ICE) powered vehicles, one issue of the electric motor propulsion system with minimized vibration damping components is NVH (Noise, Vibration and Harshness). The NVH problem is caused by output torque fluctuation of the motor system, resulting in the degradation of ride comfort and drivability.

Today, all manufacturers of vehicles are up for the challenge to abide in automobile emission control laws. Weight reduction is one of the best solutions to reduce both fuel consumption and emissions. The most effective method for the said idea is to have lightweight materials to some parts of vehicle using the FRP(Fiber Reinforced Plastics). In order to obtain good mechanical properties of FRP, continuous fiber should be used. But it is difficult to design and manufacture FRP parts using continuous fiber because of material properties and molding process. In this paper, it is used CF(carbon Fiber) and Epoxy to make a composite material. Properties of this CFRP can be predicted through analysis. Tests and simulations of specimen are performed as every step progresses for correlation. A spring can be designed to meet all requirements for specific performance. The CFRP spring is made by new devices and methods and can be applied to vehicle for practical use.

In order to achieve the emission levels required for Low Emission Vehicles (LEV) and Ultra Low Emission Vehicles (ULEV) it is necessary to obtain insight into emission reactions to the motor management systems during transient engine performance. The optimisation of transients in typical driving profiles, such as shifting, acceleration load reversal, necessitates suitable gas measurement equipment. A technique capable to resolve one combustion cycle consists in spectroscopic gas analysis by using tunable infrared diode lasers. This paper describes the available equipment and demonstrates that a diode laser system fulfils the specific demands for the analysis of transient operating characteristics of engine management systems.

The production of the BMW ALPINA B12 5.7 with Switch-Tronic transmission provides the markets of Europe and Japan with an exclusive, luxury-orientated, high performance limited series limousine. This is the first vehicle worldwide to be fitted with the progressive exhaust gas aftertreatment technology known as the Electrically Heated Catalyst (EHC), in which the effectiveness of the power utilized is increased significantly by an alternating heating process for both catalytic converters. Only since this achievement has the implementation of the EHC been viable without extensive modification to the battery and alternator. With this exhaust gas aftertreatment concept, the emissions of this high performance vehicle will fall to less than half the maximum permissible for compliance with 1996 emission standards.