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The efforts to improve automatic transmission (AT) efficiency for vehicle fuel economy are constantly continuing. In an AT the oil pump is the largest power loss factor. Therefore the effect on fuel economy is very high. The AT oil pump system has structural contradictions (high pressure × high flow), and the efforts to improve these areas are concentrated. In this paper, a two oil pumping system was designed to improve the efficiency and performance of a 6 speed AT installed in a Hybrid Electric Vehicle (HEV) [1], and the improvement was confirmed by a prototype experiment. As a result of the experiment, two pumping system was shown to improve vehicle fuel economy while reducing noise and oil pressure vibration.

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.

It is difficult to reach higher compression ratios of the gasoline engine even though higher compression ratios improve thermal efficiency. One of the barriers is large torque drop led by knocking. Extensive researches to suppress knocking of the gasoline engine have been conducted. It is focused on lowering the temperature of fuel mixture in combustion chamber at compression top dead center (TDC). This paper covers the new valvetrain system to decrease the temperature of exhaust valve bottom (combustion) side. Hollow head and stem sodium filled valve (HHSV) have shown more heat transfer from combustion chamber to valve seat insert and valve guide, and higher thermal conductivity valve seat insert (HVSI) and valve guide (HVG) help to decrease valve temperature lower by higher heat transfer.

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.

As data emerges as the most valuable resource in the world, the evolution of the related data industry is progressing faster. In this study, we tried to discover effective factors for fuel cell durability by using big data analysis techniques with accumulated vehicle actual road data (de-identified Blue Link Data). Basic analysis is performed assuming factors that are expected to have a significant impact on the fuel cell durability performance, and durability factor modeling according to the clustering between driving patterns and durability performance is used to determine. Now can see the change in durability performance. By analyzing the correlation between each driving pattern and durability performance, it is possible to know the weight of the effective factor affecting the durability. If the effective factor with high weight is improved in the actual vehicle unit, the durability performance is expected to increase, and the effect will be verified through real road operation.

End-plates are highly stiff plates that hold together the components composing a fuel cell stack, i.e. Membrane Electrode Assemblies (MEAs), Gas Distribution Layers (GDLs) and bipolar plates, offering sufficient contact pressure between them. The proper contact pressure is required not only to improve energy efficiency of a stack by decreasing ohmic loss but also to prevent leakage of fluids such as hydrogen, air, or coolant. When a fuel cell starts in cold environment, heat generated in a fuel cell stack as a result of electrochemical reactions should not be used much to increase the temperature of endplates but to melt ice inside the stack to prevent ice-blocking and to increase the temperature near the three-phase-boundary on MEAs. However, to satisfy the high stiffness required, massive metallic endplates have been used despite their inferior thermal characteristics: high thermal conductivity and large thermal inertia.

After the second worldwide oil crisis, Brazil put in place by 1975 a strategic plan to stimulate the usage of ethanol (from sugar cane), to be mixed to the gasoline or to be sold as 100% ethanol fuel (known as E100). To enable an engine to operate with both gasoline and ethanol (and their mixtures), by 2003 the “Flex Fuel” technology was implemented. By 2012 calendar year, from a total of about 3.8 million vehicles sold in the Brazilian market, 91% offered the “Flex Fuel” technology, and great majority used a gasoline sub-tank to assist on cold starts (typically below 15°C, where more than 85% of ethanol is present in fuel tank). The gasoline sub-tank system suffers from issues such as gasoline deterioration, crash-worthiness and user inconvenience such as bad drivability during engine warm up phase. This paper presents fuel injector technologies capable of rapidly electrically heating the ethanol fuel for the Brazilian transportation market.

A nano-sized PM and THC emission characteristics were investigated according to the fuel injection strategy such as a pressure and timing in the GDI engine. On the part-load condition, the particulate emissions exhibited a strong sensitivity to the injection timing. The fuel injection pressure also had a great association with the nano-particles and THC. A size of PM exhausted from the GDI engine located near 10nm on the part-load. In contrast, accumulation mode particles within 60 - 80nm mainly exhausted during the cold transient start phase. Increment of fuel injection pressure positively affected on the nano-particle and THC emissions during the start of the engine, as well.

In this research, an optical system for the detection of the flame propagation under the non-knocking and knocking conditions is developed and applied to a mass produced four cylinder SI engine. The normal flames are measured and analyzed under the steady state operating conditions at various engine speeds. For knocking cycles, the flame front propagations before and after knock occurrence are simultaneously taken with cylinder pressure data. In non-knocking and knocking cycles, flame propagation shows cycle-by-cycle variations, which are quite severe especially in the knocking cycles. The normal flame propagations are analyzed at various engine speeds, and show that the flame front on the exhaust valve side becomes faster as the engine speed increases. According to the statistical analysis, knock occurence location and flame propagation process after knock can be categorized into five different types.

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.

Hyundai Motor Company has developed hydrogen fuel cell vehicles (FCV) based on its SUV, Santa Fe. As the hydrogen fuel cell power plant runs at near ambient pressure, parasitic loss due to its operation is fully minimized and the noise level of the air supply subsystem is extremely low. The Santa Fe FCV has been built to feature roomy passenger space and cargo capacity identical to that of a standard, gasoline-powered Santa Fe, because of its compact fuel cell power plant. In addition, lightweight aluminum body-components help to keep a power-to-weight ratio similar to that of a conventional SUV. Hyundai Motor Company, as a full member of California Fuel Cell Partnership, is now operating the Santa Fe FCV's on real roads in California. In this paper, the configuration and performance test results of the Santa Fe FCV will be described.

Reducing unsprung mass of the car is a representative method to enhance the ride & handling performance and fuel efficiency. In this study, brake disc weight is reduced 15∼20% using a hybrid type material. The basis for this study is the separation of the friction surface and HAT(mounting part). Aluminum material is applied in the HAT for a light weight effect. Gray iron is applied in the friction surface section to maintain braking performance. Two types of joining between aluminum and cast iron are developed. One is the aluminum casting method utilizing a gray iron insert and the other is a bolted assembly method. Detailed structure, process and material are optimized using try-out & dynamometer experiments. The Reliability of this development is proved through durability (dynamometer and vehicle) testing.

This paper describes the development of THC reduction technologies compliant with SULEV regulations. Technologies embodied by the developmental work include improvement of fuel spay atomization, quick warm-up through coolant control shut off, and acceleration of fuel atomization for the fast rise of cylinder head temp inside the water jacket as well as the improvement of combustion state. The technologies likewise entail reduced HC while operating in lean A/F condition during engine warm-up with the cold lean-burn technology, individual cylinder A/F control for improvement of catalytic converting efficiency, aftertreatment such as thin-wall catalyst, HC absorber and EHC and etc., through vehicle application evaluation in cold start. We carried out an experimental as well as a practical study against SULEV regulations, and the feasibility of adopting these items in vehicle was likewise investigated.

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

Supervisory control strategy of a hybrid electric vehicle (HEV) provides target powers and operating points of an internal combustion engine and an electric motor. To promise efficient driving of the HEV, it is needed to find the proper values of control parameters which are used in the strategy. However, it is very difficult to find the optimal values of the parameters by doing experimental tests, since there are plural parameters which have dependent relationship between each other. Furthermore variation of the test results makes it difficult to extract the effect of a specific parameter change. In this study, a model based parameter optimization method is introduced. A vehicle simulation model having the most of dynamics related to fuel consumption was developed and validated with various experimental data from real vehicles. And then, the supervisory control logic including the control parameters was connected to the vehicle model.

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.

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 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.

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.