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This paper proposes a rolling machine that forms fine corrugated section patterns for thin sheets. A prototype of the machine was made and the performance of the machine was tested. As compared with press forming, rolling has the advantages of the high forming limit, the low forming reaction force, the easy control of the thin sheet's curve and high productivity. We confirmed these four advantages by using finite element analyses and the prototype rolling machine. Stainless steel sheets and titanium sheets, which were one of the materials with a low forming limit, were used. Firstly, the rolling showed a 1.3-times higher forming limit than the press forming in the case that a fine corrugated section pattern was formed in a stainless steel sheet of 22-mm square sizes. Secondly, the forming reaction force of the rolling was about one-twentieth of the press forming without coining, and the experimental results agreed with the finite element simulation.

A new bio-fuel i.e. the cellulosic liquefaction fuel (CLF) was developed for diesel engines. The cellulosic liquefaction fuel (CLF) was made from woods by the direct liquefaction process. CLF could not be completely mixed with diesel fuel, however CLF could be mixed with Fatty Acid Methyl Ester (FAME) and a diesel engine could be operated by CLF and FAME blends. In this study, CLF was divided into three fractions: 473 to 523 K (CLF1), 523 to 573 K (CLF2) and 573 K or more (CLF3) by fractional distillation in order to find CLF fraction which was suitable for diesel engine, and coconuts oil methyl ester (CME) was used as FAME. In the fuel droplet combustion tests, the combustion durations of CLFs were longer than those of diesel fuel and CME, and the combustion duration increased as the distillation temperature range rose, because CLF contained a lot of flame-resisting components like aromatic compounds.

A great deal of interest is focused on Homogeneous Charge Compression Ignition (HCCI) combustion today as a combustion system enabling internal combustion engines to attain higher efficiency and cleaner exhaust emissions. Because the air-fuel mixture is compression-ignited in an HCCI engine, control of the ignition timing is a key issue. Additionally, because the mixture ignites simultaneously at multiple locations in the combustion chamber, it is necessary to control the resultant rapid combustion, especially in the high-load region. Supercharging can be cited as one approach that is effective in facilitating high-load operation of HCCI engines. Supercharging increases the intake air quantity to increase the heat capacity of the working gas, thereby lowering the combustion temperature for injection of the same quantity of fuel. In this study, experiments were conducted to investigate the effects of supercharging on combustion characteristics in an HCCI engine.

Combustion experiments were conducted with an optically accessible engine that allowed the entire bore area to be visualized for the purpose of making clear the characteristics that induce extremely rapid HCCI combustion and knocking accompanied by cylinder pressure oscillations. The HCCI combustion regime was investigated in detail by high-speed in-cylinder visualization of autoignition and combustion and emission spectroscopic measurements. The results revealed that increasing the equivalence ratio and advancing the ignition timing caused the maximum pressure rise rate and knocking intensity to increase. In moderate HCCI combustion, the autoignited flame was initially dispersed temporally and spatially in the cylinder and then gradually spread throughout the entire cylinder.

Knocking combustion experiments were conducted in this study using a test engine that allowed the entire bore area to be visualized. The purpose was to make clear the detailed characteristics of knocking combustion that occurs accompanied by cylinder pressure oscillations when a Homogeneous Charge Compression Ignition (HCCI) engine is operated at high loads. Knocking combustion was intentionally induced by varying the main combustion period and engine speed. Under such conditions, knocking in HCCI combustion was investigated in detail on the basis of cylinder pressure analysis, high-speed photography of the combustion flame and spectroscopic measurement of flame light emissions. The results revealed that locally occurring autoignition took place rapidly at multiple locations in the cylinder when knocking combustion occurred. In that process, the unburned end gas subsequently underwent even more rapid autoignition, giving rise to cylinder pressure oscillations.

Rapid Controller Prototyping (RCP) is an efficient method for design & development of ECU (Electronic Controller Unit) at early stage. Usually, RCP requires firstly performing Software-in-the-loop simulation and then connecting universal controller (e.g. MicroAutoBox) to real controlled system for testing of controller functionality. During this process, it is likely that some problems related to signal configuration and real time characteristics occur and consequently give rise to unexpected results, e.g., sensor signals or controlling signals produce large deviation and possibly damage components of real system under severe condition. On the other hand, it cannot make sure that the real time characteristics of designed controller are suitable just after applying Software-in-the-loop simulation.

In the present study, a model experiment is performed in order to clarify the ventilation characteristics of car cabin. This study also provides high precision data for benchmark test. As a first step, the ventilation mode is tested, which is one of the representative air-distribution modes. Part 1 describes the properties of the flow field in the cabin obtained by the experiment. Part 2 describes the ventilation efficiencies such as the age of air by using trace gas method. The properties of flow field are measured using particle image velocimetry (PIV). The mean velocity profiles, the standard deviation distribution, and the turbulence intensity distribution are discussed. The brief comparison between experiments and predictions of computational fluid dynamics (CFD) is also presented. In the comparison between experiment and CFD, the results showed similar flow field.

Homogeneous Charge Compression Ignition (HCCI) combustion has attracted much interest as a combustion system that can achieve both low emissions and high efficiency. But the operating region of HCCI combustion is narrow, and it is difficult to control the auto-ignition timing. This study focused on the use of a two-component fuel blend and supercharging. The blended fuel consisted of dimethyl ether (DME), which has attracted interest as alternative fuel for compression-ignition engines, and methane, the main component of natural gas. A spectroscopic technique was used to measure the light emission of the combustion flame in the combustion chamber in order to ascertain the combustion characteristics. HCCI combustion characteristics were analyzed in detail in the present study by measuring this light emission spectrum.

The Homogenous Charge Compression Ignition (HCCI) engine is positioned as a next-generation internal combustion engine and has been the focus of extensive research in recent years to develop a practical system. One reason is that this new combustion system achieves lower fuel consumption and simultaneous reductions of nitrogen oxide (NOx) and particulate matter (PM) emissions, which are major issues of internal combustion engines today. However, the characteristics of HCCI combustion can prevent suitable engine operation owing to the rapid combustion process that occurs accompanied by a steep pressure rise when the amount of fuel injected is increased to obtain higher power output. A major issue of HCCI is to control this rapid combustion so that the quantity of fuel injected can be increased for greater power. Controlling the ignition timing is also an issue because it is substantially influenced by the chemical reactions of the fuel.

In this study, experiments were conducted using a blend of two types of fuel with different ignition characteristics. One was dimethyl ether (DME) that has a high cetane number, autoignites easily and displays low-temperature oxidation reaction mechanisms; the other was methane that has a cetane number of zero and does not autoignite easily. A mechanically driven supercharger was provided in the intake pipe to adjust the intake air pressure. Moreover, flame light in the combustion chamber was extracted using a system for observing light emission that occurred in the space between the cylinder head and the cylinder and in the bore direction of the piston crown. The results of previous studies conducted with a supercharged HCCI engine and a blended fuel of DME and methane have shown that heat release of the hot flame is divided into two stages and that combustion can be moderated by reducing the peak heat release rate (HRR).

Automotive fenders is one such example where specialized thermoplastic material Noryl GTX* (blend of Polyphenyleneoxide (PPO) + Polyamide (PA)) has successfully replaced metal by meeting functional requirements. The evolution of a fender design to fulfill these requirements is often obtained through a combination of unique material properties and predictive engineering backed design process that accounts for fender behavior during the various phases of its lifecycle. This paper gives an overview of the collaborative design process between Mitsubishi Motors Corporation and SABIC Innovative Plastics and the role of predictive engineering in the evolution of a thermoplastic fender design of Mitsubishi Motors Corporation's compact SUV RVR fender launched recently. While significant predictive work was done on manufacturing and use stage design aspects, the focus of this paper is the design work related to identifying support configuration during the paint bake cycle.

In this paper, emissions reduction technologies applied to high-speed direct injection (HSDI) diesel passenger car engines to meet the stricter exhaust emission legislation are described. To reduce smoke, the F.I.E. has been improved by using a radial-piston distributor pump which delivers fuel-injection-pressure up to 120MPa. Cooled exhaust gas re-circulation (EGR) system and increase in volume ratio of the combustion chamber has made it possible to increase EGR ratio and reduced nitrogen oxides (NOx) and smoke simultaneously. Furthermore, improvements in the oxidation catalyst activating temperature reduces PM at lower exhaust gas temperatures. As a result of applying these technologies, a clean and economical HSDI diesel engine for passenger cars, which complies with Japanese '98 exhaust emissions legislation and has better fuel economy than indirect injection (IDI) diesel engines (above 15%), has been developed.

A new state of the art DOC (Diesel Oxidation Catalyst) having superior light-off and exothermic activity for forced regeneration compared to conventional Pt base passive DOC, was investigated for LDD application. The DOC uses the latest Pt/Pd technology resulting cost effective DPF system. The newly developed DOC demonstrated improved catalytic activities from Pt only DOC in model gas or engine bench tests. In this study, DOC at early development stage showed excellent light-off activity in model gas and engine bench test compared to conventional Pt only DOC, however, it showed “extinction” phenomenon which is one of the deactivation mode while the post injection and it was observed when post injection operation was done at lower DOC inlet temperatures, e.g. below 250 C. Temperature profiles along diameter and length into DOC bed while active regeneration suggested extinction would be caused by fouling of supplied hydrocarbons derived from diesel fuel.

To apply a fuel economy performance to AT&CVT fluid for common use (hereinafter AT/CVT fluid) and manual transmission fluid, by optimizing fluid viscosity, a fundamental study was investigated. Generally, it is well known that the viscosity of polymer-added transmission fluids is gradually reduced, due to deterioration of the viscosity index improver caused by shear stress. An excessive viscosity reduction causes an operation failure or damage to the transmission. Considering above factor, the authors focused attention on the potential of a low viscosity formulation to improve fuel efficiency by reducing an internal stirring-resistance of the transmission. Also from the viewpoint of friction characteristics, the performance of a base oil was studied. Utilizing the EHL (Elast-Hydrodynamic Lubrication) tester [1] and vehicle tests, the performance of base oils was evaluated for the fluid development.

Flows around a forward facing step and a fence are simulated on structured grid to estimate aerodynamic noise by using direct simulation. Calculated results of sound pressure level show quantitatively good agreement with experimental results. To estimate aerodynamic noise from 3D complex geometry, a simplified side mirror model is also calculated. Averaged pressure distribution on the mirror surface as well as pressure fluctuations on the mirror surface and ground are simulated properly. However, calculated result of sound pressure level at a location is about 20dB higher than experiment due to insufficient spatial resolution. To capture the propagation of sound waves, more accuracy seems to be required.

For fuel economy improvement by lean-burn gasoline engines, extension of their lean operation range to higher loads is desirable as more fuel is consumed during acceleration. Urgently needed therefore is development of emission control systems having as high NOx conversion efficiency as three-way catalysts (TWC) even with more frequent lean operation. The authors conducted a study using catalysts loaded with potassium (K) as the only NOx trapping agent in an emission control system of a lean-burn gasoline engine.

The uniform lean methanol-air mixture was provided to the diesel engine and was ignited by the direct diesel fuel injection. The internal EGR is added to this ignition method in order to activate the fuel in the mixture and to increase the mixture temperature. The test engine was a 4-stroke, single- cylinder direct-injection diesel engine. The cooling system was forced-air cooling and displacement volume was about 211 (cm3). The compression ratio was about 19.9:1. The experiment was made under constant engine speed of 3000 (r/min). The boost pressure was maintained at 101.3 (kPa). Five values of mass flow rate of diesel fuel injection were selected from 0.060 (g/s) to 0.167 (g/s) and five levels of back pressure: 0), 26.7, 53.3, 80.0 and 106.6 (kPa) were selected for the experiment. The effect of internal EGR is varied by the back pressure level.

In order to investigate the effects of a DC electric field and its polarity on the knock intensity in a spark-ignition engine, an experimental study was carried out with a rapid compression machine. To get a good understanding of the effect of an electric field on knocking combustion, the high-speed direct photographs were taken. The ionization current measurements were also carried out using the electrode as an ionization probe The major findings of present investigation of the effects of DC electric fields on the knocking combustion process in a spark-ignition engine could be summarized as follows: It was clearly indicated that the knock intensity decreases with the increase of the electric field regardless its polarity. The knock intensity was strongly dependent upon the burned mass fraction at the onset of the end-gas autoignition, and decreased as the burned mass fraction increased.

There is an urgent need today to improve the thermal efficiency of spark- ignition (SI) engines in order to reduce carbon dioxide emission and conserve energy in an effort to prevent global warming. However, a major obstacle to improving thermal efficiency by raising the compression ratio of SI engine is the easily occurrence of engine knocking. The result of studies done by numerous researchers have shown that knocking is an abnormal combustion in which the unburned gas in the end zone of the combustion chamber autoignites. However, the combustion reaction mechanism from autoignition to the occurrence of knocking is still not fully understood. The study deals with the light absorption and emission behavior in the preflame reaction interval before hot flame reactions.

The purpose of this study is to explain the characteristics of homogeneous charge compression ignition. n-Heptane, which has the same cetane number as diesel fuel, was chosen for the fuel. A rapid compression machine was used to clarify the effects of air-fuel ratio, O2 concentration, and compression temperature on ignition delay and NOx emission. These investigations allowed the introduction of a formula for ignition delay.