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Over the past decade, there have been many efforts to generate engine sound inside the cabin either in reducing way or in enhancing way. To reduce the engine noise, the passive way, such as sound absorption or sound insulation, was widely used but it has a limitation on its reduction performance. In recent days, with the development of signal processing technology, ANC (Active Noise Control) is been used to reduce the engine noise inside the cabin. On the other hand, technologies such as ASD (Active Sound Design) and ESG (Engine Sound Generator) have been used to generate the engine sound inside the vehicle. In the last ISNVH, Hyundai Motor Company newly introduced ESEV (Engine Sound by Engine Vibration) technology. This paper describes the ESEV Plus Minus that uses engine vibration to not only enhance the certain engine order components but reduce the other components at the same time. Consequently, this technology would produce a much more diverse engine sound.

At present, the assembling order of COWL is decided according to the design of the Vehicle’s A pillar outer. Therefore when the factory layout changes, extensive costs are needed according to the changes of the A pillar outer design. Thus, this study was carried out to develop a new COWL structure that is able to determine the layout of the factory without changing the design of the A pillar outer. In addition, by adjusting the DFSS tool to COWL, the direction of the material and thickness of COWL was studied to optimize the dynamic stiffness of the body structure and pedestrian protection performance. Based on this study, the optimization of the OPEN COWL is presented.

Transient control for EV/HEV mode change takes an important role in the system of the parallel HEV, which consists of internal combustion engine (ICE), electric motor (EM), integrated starter & generator (ISG), battery, automatic transmission and clutch (that replaces the torque converter), not only ICE/EM control but also clutch engagement control are the key of it. To improve the mode change performance, this study proposes clutch slip control methods. Method 1. focuses on the open loop clutch pressure control so as to adjust target clutch transfer torque. The main idea of Method 2. is to control the clutch pressure in order to achieve the desired speed difference(Method 2-1) from each side of clutch when motor speed is faster than engine idle speed and keep target engine speed(Method 2-2) when motor speed is slower than engine idle speed. This paper defines control sequence which is scheduling the behavior of powertrain components as well.

The purpose of this paper is to identify and reduce the suspension rattle noise. First, the characteristics of the rattle noise are analyzed experimentally in the time and frequency domain. It was found that the rattle noise and vibration at shock absorber mounting point are strongly correlated. Second, the sensitivity analysis of design parameters is performed using a half car model in ADAMS. The result of the simulation model is verified by comparison with test. Finally, the influence of design parameters for the rattle noise is investigated. The study shows that the shock absorber mounting bushing is the most sensitive parameter to affect the suspension rattle noise. This paper shows how the suspension rattle noise can be improved.

A low pressure exhaust gas recirculation system (LP EGR system) enables the expansion of the EGR operating area than that of the widely used high pressure EGR system. As a result, fuel consumption and emissions can be improved. In order to meet the EU 5 emissions regulations, an exhaust throttle LP EGR system was used. The EU5 vehicles developed using this system have greater merits than other vehicles. However, because the exhaust throttle LP EGR valve is installed adjacent to the after-treatment system, the material of the LP EGR valve itself must be stainless steel in order to withstand the thermal stress, consequently, the cost is increased. Therefore, in order to achieve cost rationalization for EU6 vehicles, an intake throttle LP EGR system is developed and applied to replace the exhaust throttle LP EGR system. In order to apply the intake throttle LP EGR system, the EGR valve is installed in front of the turbo charger compressor.

Studies in the EU and the USA found higher deformation and occupant injuries in frontal crashes when the vehicle was loaded outboard (frontal crashes with a small overlap). Due to that, in 2012 the IIHS began to evaluate the small overlap front crashworthiness in order to solve this problem.A set of small overlap tests were carried out at IDIADA’s (Institute of Applied Automotive Research ) passive safety laboratory and the importance of identifying the forces applied in each structural element involved in small overlap crash were determined. One of the most important structural elements in the small overlap test is the wheel. Its interaction in a small overlap crash can modify the vehicle interaction at the crash, which at the laboratory the interaction is with a barrier. That interaction has a big influence at the vehicle development and design strategy.

Nowadays vehicle quality is rated for noise and vibration and the interior sound levels have become a major target of automotive companies. Strides have been made in reducing power train, tire and external wind noise over the years. However, HVAC and blower fan flow-induced noise reaches the interior cabin without any sound isolation and can strongly impact customer comfort. In the early stage of vehicle design, it is experimentally difficult to get an estimate of the flow pattern and sound levels. The goal of this study is to develop and validate a numerical noise prediction tool for complete HVAC systems noise, defined as the arrangement of sub-systems such as air intake duct, thermal mixing unit, blower, ducts and outlet vents. This tool can then be used during the development of vehicles to evaluate and optimize the aeroacoustics performances of the system without additional or belated experiments.

A comprehensive investigation was carried out in order to develop the idle sound quality for diesel V6 engine when the engine development process is applied to power-train system, which included new 8-speed automatic transmission for breaking down the noise contribution between the mechanical excitation and the combustion excitation. First of all, the improvement of dynamic characteristic can be achieved during the early stages of the engine development process using experimental modal analysis (EMA) & the robust design of each engine functional system. In addition, the engine structural attenuation (SA) is enhanced such that the radiated combustion noise of the engine can be maintained at a target level even with an increased combustion excitation. It was found that the engine system has better parts and worse parts in frequency range throughout the SA analysis. It is important that weak points in the system should be optimized.

Press hardenable ultra high strength steel (UHSS) is commonly used for automotive components to meet crash requirements with minimal mass addition to the vehicle. Press hardenable steel (PHS) is capable of forming complex geometries with deep sections since the forming takes place at elevated temperatures up to 900 degrees Celsius (in the Austenitic phase). This forming process is known as hot-stamping. The most commonly used PHS grade is often referred to as PHS1500. After hot-stamping, it is typically required to have a yield strength greater than 950 MPa and a tensile strength greater than 1300 MPa. Most automotive design and material engineers are familiar with PHS, the hot-stamping process, and their capabilities. What is less known is the capability of 3rd Generation advanced high strength steels (AHSS) which are cold stamped, also capable of forming complex geometry, and are now in the process of, or have recently completed, qualification at most automotive manufacturers.

The development of a high-performance battery and safe and reliable charging methods are two important factors for commercialization of the Electric Vehicles(EV) Hyundai and Ovonic together spent many years in the research on optimum charging method for Ni-MH battery This paper presents in detail the results of intensive experimental analysis, performed by Hyundai in collaboration with Ovonic An on-board Ni-MH battery charger and its controller which are designed to use as a standard home electricity supply are described In addition, a 3 step constant current recharger with the temperature and the battery aging compensator is proposed This has a multi-loop algorithm function to detect its 80% and fully charged state, and carry out equalization charging control The algorithm is focused on safety, reliability, efficiency, charging speed and thermal management (maintaining uniform temperatures within a battery pack) It is also designed to minimize the necessity for user input.

This paper introduces mathematical equations for power loss calculations of major automatic transmission components. It also presents a theoretical investigation on contributions of each component's power loss to transmission total power losses. A computer program for automatic transmission efficiency calculation has been developed based on mathematical equations. Efficiency calculations for the Hyundai A4BF1 electronic 4 speed automatic transmission has been executed in order to validate the program. The calculated efficiency under various input and operating conditions - such as different input torque & RPM, transmission gear state, ATF temperature, torque converter clutch on/off - showed quite good agreement with the test results.

Ride quality of heavy duty truck becomes important item, due to long distance transfer and long time driving This study describes how to determine and evaluate design parameters related to cab suspension system through time and frequency domain analysis The spring and damper-stiffness of the cab suspension system were optimized by two objective functions, which consist of cab pitching acceleration peak level and vibrational absorbed power Cab pitching is the main item which should be studied for ride quality In an attempt at optimizing, we made use of “Taguchi Method”,which was applied to experiments and simulation. We made truck cab model by use of DADS, which is dynamic analysis software,in order to find out the cab motions The results of simulation and test of a heavy duty truck gave us the optimum design parameters, which were verified and confirmed by real vehicle test

This paper describes the ground system model and algorithm for a ground level simulation tool. First, the modeling of an automotive ground system will be discussed and the algorithm for a simulation tool will be explained. We divided the model into a ground tree and a ground body. The ground tree model consists of resistance formed by the wires that connect the load to ground point with various structures and the ground body model consists of resistance between ground points in the car body. The wires with large current, such as engine ground cable, was modeled in detail by dividing the resistance into wire, bolt, and clamping resistance, in order to simulate the effect of increased contact resistance after durability test. The algorithm of the ground level simulation tool was designed to adjust the currents of the alternator, battery, and ground points in order to evaluate the various driving and load conditions.

The aim of this paper is to computationally investigate the combustion behavior and energy recovery processes of a six-stroke gasoline compression ignition (6S-GCI) engine that employs a continuously variable valve duration (CVVD) technique, under highly diluted, low-temperature combustion (LTC) conditions. The effects of variation of parameters concerning injection spray targeting (number of fuel injector holes. injector nozzle size and spray included angle) and combustion chamber geometry (piston bowl design) are analyzed using an in-house 3D CFD code coupled with high-fidelity physical sub-models with the Chemkin library in conjunction with a skeletal chemical kinetics mechanism for a 14-component gasoline surrogate fuel.

Presented in this research is methodology for modeling the behavior of an automotive ECU (Electronic Control Unit) to verify in a production system. The methodology of this paper is to verify the defects of ECU products during in a real operation, before the defective ECU equipped to an automobile. The performance of an ECU operation is dependent on not only the specification of a hardware device, but also a software program installed in the memory of an ECU. The software program of an ECU is able to be validated before installation, but the validation process is usually executed in a very controllable environment. In order to consider the software program which is frequently changeable in practice, the verification methodology of ECU products as the hardware device and software program integrated is required for detecting defective ECU products caused by inappropriate software program during in manufacturing processes.

Fatigue behavior of two types of automotive steel, quenched and tempered SUJ2 and carburized SCM820PRH, which are applied as powertrain parts are studied. These two types of steel are different in their hardness distribution from surface to core. The hardness of quenched and tempered SUJ2 is homogenous, in contrast to that of carburized SCM820PRH (SCM) which decreases from surface to core. These steels are investigated in terms of their monotonic tensile properties and fatigue behavior. A number of predictive methods were used to describe the fatigue behavior of these steels. A simple predictive method is based on approximation of S-N curve from ultimate tensile strength. The well-known Murakami’s defect area method was also applied for the prediction of the high cycle fatigue strength.

The aim of this work is to investigate the current carburizing heat treatment and subsequently to develop new modified heat treatment with increase of surface hardness and corrosion resistances for next generation of injector parts. Considered parts are stopper (SUS303) and position ring (1.4305) of high pressure injector in powertrain. At first, current carburized components are investigated and resulted: hardness (HV100 mN) 802-959, layer thickness of 17.85-24.59 μm, corrosion resistance was maximum 1 hour at 8.25% NaClO solution. New modified heat treatment is Super Saturated NitroCarburizing (SSNC) which is generated with nitrogen and carbon sourcing gas in temperature range of 350-450°C. The process in detail is: nitrogen purging and heating, activation at 360°C for 1 hour, heating, nitrocarburizing at 450°C for 9 or 12 hours, and cooling. The nitrogen rich S-phase was formed at surface and carbon rich S-phase was formed at subsurface.

Broadband active noise control algorithms require high-performance so multi-channel control to ensure high performance, which results in very high computational power and expensive DSP. When the control filter update part need a huge computational power of the algorithm is separated and calculated by the server, it is possible to reduce cost by using a low-cost DSP in a local vehicle, and a performance improvement algorithm requiring a high computational power can be applied to the server. In order to achieve the above goal, this study analyzed the maximum delay time when communication speed is low and studied response measures to ensure data integrity at the receiving location considering situations where communication speed delay and data errors occur.