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A new material recycling technology for crosslinked rubber was developed using the continuous reactive processing method. In this process of producing reclaimed rubber, breakage of crosslinking points in the crosslinked rubber occurs selectively under the controls of shear stress, reaction temperature, and internal pressure in a modular screw type reactor. Deodorization during the process has also become possible by a newly developed method. The reclaimed rubber obtained from rubber waste generated from both automobile manufacturing products and post-consumer products shows excellent mechanical properties applicable to new rubber compounds. Furthermore, an enhanced rubber recycling process for producing thermoplastic elastomer (TPE) based on rubber waste has been established. The obtained TPE exhibits highly recoverable rubber elasticity and mechanical properties comparable to commercial TPE.

Natural gas homogeneous charge compression ignition (HCCI) engines require high compression ratios and intake air heating because of the high auto-ignition temperature of natural gas. In the first study, the natural gas fueled HCCI combustion with internal exhaust gas recirculation (EGR) was achieved without an intake air heater. The effects of the combustion chamber configuration, turbocharging, and external EGR were investigated for expanding the operating range. As a result, it was cleared that the combination of internal / external EGR and turbocharging is effective for expanding the HCCI operational range toward high loads. Meanwhile, the HCCI combustion characteristics at high engine speeds were unstable because of an insufficient reaction time for auto-ignition. Although the engine operation with a richer air-fuel ratio was effective for improving the combustion stability, the combustion noise (CN) was at an unacceptable level.

The catalyst of the crystalline ceramics known as a perovskite-type oxide was designed and controlled at the atomic level in order to create a new function for self-regeneration of precious metals in a usage ambience without auxiliary treatment. We have already reported that a catalyst with Pd supported on the perovskite-type oxide has higher activity than a catalyst with Pd supported on alumina. It was also found that Pd supported on the perovskite catalyst is finely dispersed [1, 2 and 3] The object of this study was to investigate the mechanism of self-regeneration by using hyper-analytical facilities. XAFS analysis, at SPring-8 (8 GeV), revealed that Pd is in six-fold coordinations with oxygen in a perovskite crystal, which indicating that Pd occupies the B site of the unit formula of ABO3 in the perovskite crystal structure under oxidation atmosphere.

The stoichiometric direct injection gasoline engines have higher torque performance than the port injection engines, as the volumetric efficiency can be increased due to the cooling effects of charging air by the fuel evaporation in the cylinder. They need only 3-way catalyst, leading to the cost down. However there exists the injection timing (region) that increased volumetric efficiency does not lead to higher torque. In order to investigate the phenomena, the in-cylinder mixture formation process has been analyzed by the LIF and the CFD techniques. As the results, it has been revealed that the phenomena are caused by the inhomogeneous mixture distribution before the ignition timing.

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.

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.

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.

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.

Further improvements in catalyst performance are required to help protect the atmospheric environment. However, from the viewpoint of resource availability, it is also necessary to decrease the amount of precious metals used at the active sites of the catalyst. Therefore, a high-performance three-way catalyst with an advanced coating layer has been developed to lower the amount of precious metal usage. Fuel efficiency improvement technologies such as high compression ratios and a large-volume exhaust gas recirculation (EGR) generally tend to increase the ratio of hydrocarbons (HC) to nitrogen oxides (NOx) in exhaust gas. This research focused on the palladium (Pd) loading depth in the coating layer with the aim of improving the hydrocarbon (HC) conversion activity of the catalyst.

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.

A concept of dual-fuel, Premixed Compression Ignition (PCI) combustion controlled by two fuels with different ignitability has been developed to achieve drastically low NOx and smoke emissions. In this system, isooctane, which was used to represent high-octane gasoline, was supplied from an intake port and diesel fuel was injected directly into an engine cylinder at early timing as ignition trigger. It was found that the ignition timing of this PCI combustion can be controlled by changing the ratio of amounts of injected two fuels and combustion proceeds very mildly by making spatial stratifications of ignitability in the cylinder even without EGR, as preventing the whole mixture from igniting simultaneously. The operable range of load, where NOx and smoke were less than 10ppm and 0.1 FSN, respectively, was extended up to 1.2MPa of IMEP using an intake air boosting system together with dual fueling.

The effect of the chemical reactivity of diesel fuel on PM formation was investigated using a flow reactor and a shock tube. Reaction products from the flow-reactor pyrolysis of the three diesel fuels used for the engine tests in Part 1(1) (“Base”, “Improved” and Swedish “Class-1”) were analyzed by gas chromatography. At 850C, Swedish “Class-1” fuel was found to produce the most PM precursors such as benzene and toluene among the three fuels, even though it contains very low amounts of aromatics. The chemical analyses described in Part 1 revealed that “Class-1” contains a large amount of branched and cyclic structures in the saturated hydrocarbon portion of the fuel. These results suggest that the presence of such branched and ring structures can increase exhaust PM emissions.

The effects of an increasing boost pressure, a high EGR rate and a high injection pressure on exhaust emissions from an HSDI (High Speed Direct Injection) diesel engine were examined. The mechanisms were then investigated with both in-cylinder observations and 3DCFD coupled with ϕT-map analysis. Under a high-load condition, increasing the charging efficiency combined with a high injection pressure and a high EGR rate is an effective way to reduce NOx and soot simultaneously, which realized an ultra low NOx of 16ppm at 1.7MPa of IMEP (Indicated Mean Effective Pressure). The flame temperature with low NOx and low soot emissions is decreased by 260K from that with conventional emissions. Also, the distribution of the fuel-air mixture plot on a ϕT-map is moved away from the NOx and soot formation peninsula, compared to the conventional emissions case.

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.