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Non-equilibrium all-atom MD simulations are used to study the traction properties of hydrocarbon fluids. A fluid layer is confined between two solid Fe plates under the constant normal force of 1.0 GPa. Traction simulations are performed by applying a relative sliding motion to the Fe plates. Shear behaviors of nine hydrocarbon fluids are simulated on a sufficiently large film thickness of 6.7 nm, and succeeded in reproducing the order of the experimental traction coefficients. The dynamic mechanism of the momentum transfer on layers of fluid molecules are analyzed focusing on the intermolecular interactions (density profile, orientation factor, pair-correlation function) and intramolecular interactions (intramolecular interaction energy, conformation change of alicyclic ring). In contrast to the case of n-hexane, which shows low traction due to a fragile chain-like interaction, other mechanisms are obtained in the high traction molecules of cyclohexane, dicyclohexyl and santotrac 50.

To meet diesel emission regulations, high injection pressure is demanded for the supply pump of electronically controlled common-rail type injection system. DENSO has produced common-rail type injection system in 1999. Cam and roller to generate high pressure in the supply pump at the system are composed of steel and silicon nitride ceramics, and are rolling contact under light oil lubrication. Therefore, rolling contact fatigue failure had been concerned. In order to assure the components, we estimated the influence on the materials and the lubrication on the rolling fatigue strength of silicon nitride ceramics, the contact fatigue life was tested under oil lubrication.

In order to reduce traffic accident casualties, sophisticated safety systems have been developed and are continuously being upgraded in today's passenger vehicles. One system showing growth in the global automotive industry is a feature currently available on high-end passenger cars, Vehicle Stability Control (VSC). VSC can control side slipping, an unstable phenomenon which can lead to critical accidents. VSC systems are multi-functional systems that include an acceleration sensor to detect forces applied to the vehicle. Acceleration sensors sometimes referred to as G sensors are indispensable and are one of the key sensors for vehicle safety systems. New safety systems require acceleration sensors with high sensitivity and accuracy. We have achieved these increased requirements by adopting a unique stacked IC structure.

If a vehicle is left in a humid environment, the coefficient of friction between the brake pads and discs increases, generating a discomforting noise during braking called brake squeal. It is assumed that this increase in the coefficient of friction in a humid environment is the effect of moisture penetrating between the brake friction surfaces. Therefore, this paper analyzes the factors causing coefficient of friction variation with moisture between the friction surfaces by dynamic observation of these surfaces. The observation was achieved by changing the disc materials from cast iron to borosilicate glass. One side of the glass brake disc was pushed onto the brake pad and the sliding surface was observed from the opposite side by a charge coupled device (CCD) camera. First, a preliminary test was carried out in a dry state using two pad materials with different wear properties to select the appropriate pad for observing the friction surfaces.

Methyl esters of saturated/unsaturated higher aliphatic acids (FAMEs) and a FAME of waste cooking oil (WCOME) were heated at 120°C in an air gas flow. The samples were analyzed before and after heating, using six different methods including electrospray ionization mass spectrometry. As a result, the samples after heating were found to contain low molecular weight aliphatic compounds and oligomers of the FAME. Based on the chemical structure of these oxidation products, reaction schemes were proposed for the deterioration of FAMEs. In addition, two unsaturated FAMEs containing 2,6-di-t-butyl-p-cresol (BHT) were similarly heated and analyzed to examine the effect of BHT on the oxidation of these FAME.

The effect of GTL diesel fuel on organic materials used in fuel delivery systems of vehicles was investigated. Specimens made from 16 kinds of organic materials were immersed in GTL diesel fuels synthesized at Refinery-A and Refinery-B (referred to as GTL-A and GTL-B, respectively) and then subjected to tensile testing. The tensile test results revealed that elongation of the nylon sample immersed in GTL-A was extremely small, about 4% of that of untreated nylon. In the light of this finding, the GTL diesel fuels and nylons before and after immersion test were analyzed in detail using about 20 analysis methods to determine the cause for poor elongation. The following points were found. (1) GTL-A consisted of low molecular-weight paraffins. (2) GTL-A had low molecular-weight i-paraffins. (3) The nylon immersed in GTL-A contained low molecular-weight paraffins. (4) The paraffins in the nylon immersed in GTL-A were richer in i-paraffins than the original GTL-A.

Behavior of sprays formed by slit nozzle as well as swirl nozzles with the spray cone angle in the range of 40° ∼110 ° were studied in a constant volume N2 gas chamber. The fuels used are iso-pentane, n-heptane, benzene and gasoline. The ambient pressure and temperature were raised up to 1.0 MPa and 465 K, respectively. The injection pressure was mainly set at 8 MPa. Spray penetrates at an almost constant speed for a while after injection start and begins to decelerate at a certain point. This point was judged as breakup point, based on a momentum theory on spray motion, the observation of spray inside and the analysis of the spray front reacceleration which occurs under highly volatile condition.

Toyota participated in Formula One1 (F1) Racing from 2002 to 2009. As a result of the downturn in the world economy, various engine developments within F1 were restricted in order to reduce the cost of competing in F1. The limit on the maximum number of engines allowed has decreased year by year. Toyota focused on the engine performance deterioration due to the combustion chamber deposits. In 2009, Toyota was successful in reducing around 40% of the deterioration by making combustion chamber cleaner in cooperation with ExxonMobil. This contributed to good result of 2009 F1 season for Toyota, including two second place finishes.

The backward flow of the hot burned gas surrounding a diesel flame was found to be one of the factors dominating the set-off length (also called the lift-off length), that is, the distance from a nozzle exit into which a diffusion flame cannot intrude. In the combustion chamber of an actual diesel engine, the entrainment of the surrounding gas into a spray jet from a multi-hole nozzle is restricted by the walls and adjacent spray jets, which induces the backward flow of the surrounding gas. A new momentum theory to calculate the backward flow velocity was established by extending Wakuri's momentum theory. Shadowgraph imaging in an optical engine successfully visualized the backward flow of the hot burned gas.

This paper describes the customized power MOSFET technologies that we have developed over the last twenty years for automotive use. During the 1980s we developed thermal-destruction free power MOSFETs with monolithically integrated polysilicon thermal sensing diodes (PTSDs), which are in wide use around the world. In the 1990s, we succeeded in developing the CONCAVE-DMOSFET, the first vertical channel power MOSFET for automotive use that achieves both lower dissipation and optimal gate reliability. Recently, we have greatly advanced power MOSFET performance through the development of PTOx trench-gate MOSFETs (TMOSs), where PTOx stands for partially thick gate oxide film structure. The PTOx structure consists of thick oxide around the trench top, thin oxide on the trench sides, and thick oxide at the trench bottom, and is formed using a simple process that we developed.

Recently, enhancements to product quality from the standpoint of consumer protection have become a prerequisite in responding to the increase of social awareness of product quality. The results of our researches[1, 2] on quality problems suggest that they were often induced by a known contributing factor, which means many of them could have been prevented if the design engineers and/or design reviewers had “smelled” the known factors. This report describes the steps taken by the System Control Components Product Division in DENSO Corporation in order to make a change to the existing quality control strategy by providing a new systematic tool for conveying know-how needed to prevent recurrences of quality problems.

Countries and regions around the world are tightening emissions regulations in reaction to the increasing awareness of environmental conservation. At the same time, growing concerns about the depletion of raw materials as vehicle ownership continues to increase is prompting automakers to look for ways of decreasing the use of platinum-group metals (PGMs) in the exhaust systems. This research has developed a new catalyst with strong robustness against fluctuations in the exhaust gas and excellent nitrogen oxide (NOx) conversion performance. This catalyst incorporates rhodium (Rh) clusters with a particle size of several nanometers, and stabilized CeO2-ZrO2 solid-solution (CZ) with a pyrochlore crystal structure as a high-volume oxygen storage capacity (OSC) material with a slow O2 storage rate.

We have developed a high capacity electromagnetic clutch by means of Si-containing diamond-like carbon (DLC-Si) coating. The durability of the new clutch is enhanced up to 8 times higher than that of the conventional one. Such a superior performance is due to several tribological properties of the DLC-Si film and micro morphology on the clutch surface. In particular, the DLC-Si plays a significant role in maintaining the groove shape of the clutch and giving sufficient friction in fluid, which is required for a drivetrain device. Besides, our deposition process (using direct current plasma-assisted chemical vapor deposition) has afforded homogeneous DLC-Si-coated clutches in large quantities. These techniques have enabled us to reduce the number of clutch discs per coupling and achieve a more compact and higher capacity AWD coupling at a lower cost.

One of typical outcome of the desire for increasing passenger comfort is that especially for deodorant efficiency. Since customers are becoming so sensitive about cabin odor, development of more effective deodorant filter is strongly required. Out side of vehicle, which most being disliked is diesel odor, therefore, analysis on this diesel gas and investigation to identity the ingredient for the main cause of the strong odor were executed, and found that acetaldehyde gas is the one. Therefore, identification of the chemical that adsorb acetaldehyde gas with being impregnated in activated carbon was required, since activated carbon itself does not have ability of adsorbing acetaldehyde gas, and finally found appropriate chemical, vitamin Bx. At the end of this report, sensory evaluation result by twenty panelists with deodorant type cabin air filter impregnated with vitamin Bx, and its efficiency for deodorant will be shown at the end of this report.

This paper deals with a case where H∞ control is applied to a basic control logic of a rack-assisted Electric Power Steering (EPS) system. In the body, the following three key features are described: Construction of the target controlled model including a vehicle Controller design for the model H∞ controller performance verification In this paper, it has been confirmed that H∞ control is valid as a basic control logic for the EPS system.

In conventional gasoline engine vehicles, three-way catalysts are used to simultaneously remove HC, CO and NOx from the exhaust gas. The effectiveness of the catalyst to remove these harmful species depends strongly on the oxygen concentration in the exhaust gas. Deterioration of three-way catalyst results in a reduction in its purification activity and OSC (oxygen storage capacity). In this investigation, additive elements were used to enhance the durability and OSC of the catalyst support material. An optimized formulation of a CeO2-ZrO2 and a ZrO2 material was developed to have excellent durability, improved OSC, enhanced interaction between precious metals and support materials, and increase thermal stability. Using these newly developed support materials, catalysts with increased performance was designed.

Growing concerns about the depletion of raw materials as vehicle ownership continues to increase is prompting automakers to look for ways of decreasing the use of platinum-group metals (PGMs) in the exhaust systems. This research has developed a new catalyst with strong robustness against fluctuations in the exhaust gas and excellent nitrogen oxide (NOx) conversion performance. One of the key technologies is a new OSC material that has low surface area (SA) and high OSC performance. We enhanced the pyrochlore- ceria/zirconia (CZ) which has a very small SA. In order to enhance the heat resistance and promote the OSC reaction, we selected and optimized the additive element. This material showed high OSC performance especially in the temperature range of 400 degrees or less. Another key technology is washcoat structure that has high gas diffusivity by making connected pore in the washcoat (New pore forming technology).

In order to reduce the energy consumption of the automotive air conditioning system, adsorption heat pump (AHP) system is one of the key technologies. We have been developing compact AHP system utilizing the exhaust heat from the engine coolant system (80-100 °C), which can meet the requirements in the automotive application. However, AHP systems have not been practically used in automotive applications because of its low volumetric power density of the adsorber. The volumetric power density of the adsorber is proportional to sorption rate, packing density and latent heat. In general, the sorption rate is determined by mass transfer resistance in primary particle of an adsorbent and heat and mass transfer resistance in packed bed. In order to improve the volumetric power density of the adsorber, it is necessary to increase the production of the sorption rate and the packing density.

According to the principle of pH measurement, an on-board type engine oil deterioration sensor has been developed. The developed sensor is composed of a Pb and oxidized stainless steel electrodes. The sensor signal shows a good linear relationship to the quasi-pH value of the oil. Especially in the region where the oil deterioration proceeds, the remaining basic additives in the oil is easily estimated from the sensor signal.

Fretting fatigue mechanism of rapidly solidified powder aluminum alloy has been studied by model tests and analysis using fracture mechanics. The factors which influences upon fretting scar formation and fatigue crack propagation were the main concerns in the present work. In order to investigate the mechanism of fretting scar formation in detail, fretting wear tests in which small amplitude oscillatory movement occurred in the contact region were carried out. Test results showed that the size of fretting scar increased with increasing tangential force coefficient. Characteristics of fretting fatigue crack propagation were analyzed using fracture mechanics. The fatigue limits under fretting conditions were estimated by connecting the applied stress intensity factor range calculated from applied cyclic stress and tangential force, with the threshold stress intensity factor range of small crack.