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Hardware-in-the-Loop Simulation allows ECUs to be tested in a simulated environment in closed loop. Engines, vehicles, and other components the ECU normally controls are replaced by high-fidelity models executed on a real-time computer system. This paper shows that today's hardware/software technology makes comprehensive and powerful low-cost desktop simulators feasible. It is also shown that it is now possible to use the same tools for Hardware-in-the-Loop Simulation that have been used in the control development.

In today's automotive development environment it is necessary to look at the totality of an automotive system. For this approach is necessary in order to optimize system designs for reliability, manufacturability and cost. Optimization in the case of the automotive system or subsystems, entails performing trade-off studies on the different components taking into account their interactions. In doing so it is necessary to employ a mixed domain simulation tool. In the case of the Cranking and Charging System electrical, mechanical and thermal domains must be co-simulated. The focus of this paper will be to show how a typical Cranking/Charging system can be analyzed and how the appropriate design decisions can be made.

Simulation is by now considered an essential activity prior to the implementation of complex, embedded real-time systems such as automotive control units. However, the models required for a meaningful systems simulation are often heterogeneous -(such as software, hardware, hydraulics, mechanics etc.) and developed in parallel using different tools from different vendors, thereby making comprehensive system simulations very hard. An open architecture for cosimulation of heterogeneous systems and its first implementation within the MATRIXx tool family, based on the Common Object Request Broker Architecture (CORBA) is described. It allows plug-and-play cosimulations between a wide range of simulation tools and can serve as the foundation of sophisticated virtual prototyping and systems simulation activities.

KIA has completed the development of the future DOHC 16 valve spark ignition engine designated the T-series. An all new design was devised for the T-series engine which is being produced on an entirely new plant. This engine has many positive features such as low emission level, good combustion stability, low noise and vibration. The basic construction of the T-series engine is characterized by 4 cylinder belt-driven DOHC engine, state-of-the-art combustion chambers with tumbling intake ports and a valve angle of 45, deep skirt cylinder block, laminated metal cylinder head gasket, aluminum structural oil pan, and a six ribbed serpentine belt driven accessory system. Thorough durability testing was carried out on all production parts for the first engine of the T-series; called the T8D engine, of 1.8 litre displacement. Mass production of the T8D engine, installed in the new KIA CREDOS, began in July 1995.

For a 1997 model year passenger car, Honda has released an all-new 3.0 liter, transversely mounted, SOHC VTEC (Variable Valve Timing and Lift Electronic Control) V6 engine. This compact, light-weight, state-of-the-art V6 engine achieves 147 kW @ 5500 rpm, improves fuel economy, and uses regular unleaded fuel. This is the world's first SOHC VTEC V6 engine, and the first V6 to be manufactured in the United States by Honda.

Modern passenger car engines are designed to operate at increasingly higher rated engine speeds with more internal parts (multi-valve engines) requiring lubrication. The paper presents results of research and development activities to reduce the actual feed rate of the oil consumers to their real requirements depending on the most significant influence parameters. Based on these results an optimization strategy is presented which combines CAE tools with data from experimental work. In the conclusion of the paper recommendations are summarized to show the optimization potential of actual lubrication and ventilation systems concerning design. power input respectively oil consumption.

Ford introduced a new in-line 4-cylinder 2.3L DOHC 16-valve engine in its European D-class Scorpio vehicle. The engine is based on the proven 2.0L-DOHC engine with 8 or 16 valves. The new engine replaces the 2.0L DOHC 8-valve version. Primary focus of the development of this new 2.3L engine was on the noise and vibration improvement, both for the engine and for the vehicle interior noise. One measure to achieve this target was the application of balance shafts. In this paper, the development of the new engine will be described from the design stage to the production version. It will focus on the design of the balance shaft housing and all relevant engine NVH features. The various stages of the design and detailed optimization are explained. The NVH prediction by CAE methods is verified with experimental results. The influence of optimized components like the oil pan, front cover and the chain tensioner on the noise behavior will be discussed.

Casting technology developmentshave led to a manufacturing process that allows the casting of thin wall (2-3mm) heat resistant ferritic stainless steel exhaust manifolds which can replace stamped and tubular weldments as well as iron castings where temperature requirements are increased. This casting process combines the thin wall and clean metal benefits of the counter gravity, vacuum-assist casting process using thin, light-weight bonded sand molds supported by vacuum-ridgidized sand. This combination is called the LSVAC (Loose Sand Vacuum Assisted Casting) process, a patented process. This process will significantly contribute to the growth of near-net shape steellstainless steel castings for automotive and allied industries. For exhaust manifolds, a modified grade of ferritic stainless steel with good oxidation resistance to 950°C in high dew point synthetic exhaust gas atmospheres was developed.

Gas shielded metal arc welding is generally applied to automobile chassis parts. However, the weld parts with the E-coat show poor corrosion resistance. Therefore, the corrosion mechanism of the weld parts was investigated. The results found two reasons why the weld parts corroded faster than the non weld parts:(1)inadequate phosphating (2)defects in the E-coat. After detailed investigation, it was clarified that the major cause of poor corrosion resistance was the defects in the E-coat caused by slags formed on the surface of the weld bead. Therefore the amount of slag has to be decreased to improve the corrosion resistance. The effect of shielding gas composition on the amount of slag was then investigated. In the case of Ar and oxidizing gas mixture, the corrosion resistance improved as the oxidizing gas content decreased. This was due to the reduction of slags.

A model of a timing belt analyzed by FEM (a general non-linear finite element program:ABAQUS) successfully confirmed the mechanism that generates belt cord stress. Analysis revealed a good correlation between the experimental and computed results of stress distribution of the belt cord. Through calculation, it was discovered that belts broke near the tooth root, which is the point of maximum stress of the cord.

The main result of this paper is a real-time closed loop demonstration of spark advance control by interpretation of ionization current signals. The advantages of such a system is quantified. The ionization current, obtained by using the spark plug as a sensor, is rich on information, but the signal is also complex. A key step in our method is to use parameterized functions to describe the ionization current [1]. The results are validated on a SAAB 2.3 1, normally aspirated, production engine, showing that the placement of the pressure trace relative to TDC is controlled using only the ionization current for feedback.

Present corrosion testing procedures for brake fluids assess the properties of fresh fluids under some forms of environmental stress (e.g., water content, elevated temperature). These tests may not accurately predict corrosion protection properties of fluid after the years of continuous service typical of North American practice. This paper describes the development of laboratory accelerated aging procedures which reproduce the chemical changes occurring in brake fluids during long-term service. Short-duration vehicular tests with these lab-aged fluids have reproduced specific modes of corrosion previously observed only after long-term customer use.

This paper presents a system concept for detecting combustion misfire. The relevant research grew out of the more stringent requirements for On-Board Diagnostic systems (OBDII) mandated by the California Air Resources Board (CARB), effective as of model year 1997 onward. The system concept is based on evaluation of variations in crankshaft speed. Processes using engine roughness are applied in non-critical operating areas and/or on engines with a small number of cylinders. The modulation process is used in more critical areas. Research was done using a 12-cylinder engine and indicated the potential to comply with the California Air Resources Board's regulations for the model year (MY) 1997 and later.

The influence of variable air-fuel ratio inside a spark ignition engine is examined by the use of an ionization sensor. The measured ion currents are used for predicting the local air-fuel ratio in the vicinity of the spark plug. In order to support the results, a theoretical analysis has been made. An instationary chemical kinetic model burning a mixture of iso-octane and n-heptane is used for the calculations. The results are used to reconstruct the crank angle resolved ion current that has been measured in an engine. This technique has been developed in order to offer a supplementary low-cost facility of controlling the air-fuel ratio within the combustion chamber of an engine.

Wire bonding has become one of the primary methods of interconnection for automotive-electronic units. This includes: ignition modules, pressure sensors, voltage regulators, anti-lock braking modules, air-bag systems, distributoriess ignition modules, etc. As the technologies in the automotive field increases, both the wire bonders and the wire have to keep pace. One of the improvements over the past few years was the development of corrosion resistant wire used for automotive-electronic applications. Corrosion resistant wire is unique in that there are some essential dopants in the wire that prevent the wire from physical damage.

Results of experimental studies of the JDC (Jet Dispersion Combustion) method to stimulate burning in SI piston engines are presented. The principle of the method is to disperse combustion gases originated from the homogeneous charge flame kernel throughout whole combustion chamber by means of the gas jet introduced in the chamber from outside. Emphasis is placed on relationships between system parameters and pollutant emissions. Results of exhaust gas composition measurements are presented at various jet directions. In general, at any engine load, the external air injection tends to decrease CO and HC contents in the exhaust gas, and NOx concentration remains basically unchanged. At idling conditions, it was possible to decrease remarkably CO concentration (even below 0.2 % by volume) without increasing HC and NOx levels. The measured exhaust gas composition was strongly dependent on the injection direction.

This paper describes a thick film ZrO2 NOx sensor feasible for diesel and gasoline engine applications, and introduces modification items from the previous concept design.(1) The modification items comprise simplifying the sensing element design to reduce output terminals for package design and applying temperature control to the sensing element in order to minimize sensor performance dependency on gas temperature. The NOx sensor indicates a stable linear signal in proportion to NOx concentration in a wide range of temperature, A/F and NOx concentration as a practical condition on both gasoline and diesel engines. The NOx sensor shows a good response in hundred msec. and a sharp signal following NOx generation in a transient state as well. Besides, another type of a NOx sensor is proposed for low NOx measurement in a practical use, by an electromotive force(EMF) voltage instead of a pumping current.

The actuator is the essential part of the automatic control system of the diesel crankshaft rotation frequency. The actuator on base of the linear electromagnet is considered. The purpose of this paper is to determine the conditions of receiving minimum of the weight and to optimize the parameters of the actuator. The exact calculation of the leakage of the magnetic flux and the parameters of magnetic circuit allows to find the characterisctics of the actuator precisely. In order to investigate the magnetic field in the axi-simmetric and planar complex shaped bodies such a stator and rotor of the electrical machines we have to solve Maxwell equations in these bodies. In this paper we use the Finite element method to calculate the magnetic field because it makes possible to avoid the dificulties connected with the complex shape of the system. The results of this paper allows to choose the material, configuration and parameters of the actuator optimally.

An experimental study was performed, using cycle-resolved laser Doppler velocimetry (LDV) technique, to characterize the exhaust flow structure inside a catalytic converter retro-fitted to a firing four-cylinder gasoline engine over different operating conditions. A small fraction of titanium (IV) isopropoxide was dissolved in gasoline to generate titanium dioxide during combustion as seeding particles for LDV measurements. It was found that in the front plane of the catalytic monolith, the velocity is highly fluctuating due to the pulsating nature of the engine exhaust flow, which strongly depends on the engine operating conditions. Under unloaded condition, four pairs of major peaks are clearly observed in the time history of the velocity, which correspond to the main exhaust events of each individual cylinder.

A computer model has been developed to predict exhaust hydrocarbon emission levels from spark ignition engines. The model incorporates the two presently accepted main sources of unburned hydrocarbons: the top land piston-ring crevice and the oil film absorption/desorption process. The main innovation shown by the model is the consideration of the combustion period in the calculation of the unburned hydrocarbons concentration. Both the oil film and the crevice are divided into small volume elements. The flame position during combustion is monitored, so that it can be determined for each volume element if absorption or desorption in the oil film is taking place, and if the flow to the crevice is of burned or unburned mixture. The model shows that failure to consider the combustion event leads to an underestimation of about 18% of the HC desorbed from the oil film, and to an overestimation of around 14% of the HC released from the crevice.