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This study attempted to faithfully reproduce and scientifically analyze the process of formation of the exhaust pipe of the winning RA272 engine used in Formula One in the 1960's, using the waza (skills) employed in its fashioning, which have been handed down by its makers. This analysis showed that the manual bending method, used to create the RA272 exhaust pipe, which was filled with sand and bent while being flame-heated, without the use of figures or molds, was superior to the mechanical bending method of that time, from the standpoint of short-term period of production. We have determined that the pipe displays that the microstructure of the material remains stable, even at exhaust temperatures of 700°C to 900°C, and that useful information on the pipe's shape stability and mechanical strength has been provided.

In order to clarify future automobile technologies and fuel qualities to improve air quality, second phase of Japan Clean Air Program (JCAPII) had been conducted from 2002 to 2007. Predicting improvement in air quality that might be attained by introducing new emission control technologies and determining fuel qualities required for the technologies is one of the main issues of this program. Unregulated material WG of JCAPII had studied unregulated emissions from gasoline and diesel engines. Eight gaseous hydrocarbons (HC), four Aldehydes and three polycyclic aromatic hydrocarbons (PAHs) were evaluated as unregulated emissions. Specifically, emissions of the following components were measured: 1,3-Butadiene, Benzene, Toluene, Xylene, Ethylbenzene, 1,3,5-Trimethyl-benzene, n-Hexane, Styrene as gaseous HCs, Formaldehyde, Acetaldehyde, Acrolein, Benzaldehyde as Aldehydes, and Benzo(a)pyrene, Benzo(b)fluoranthene, Benzo(k)fluoranthene as PAHs.

This paper introduces the Japanese standards and regulations of automobiles with brakes as the central subject and clarifies the difference from those of Europe and USA by comparison. Further, this paper describes not only the application status of the standards and regulations in Japan but also the features of structure and performance of Japanese trucks that are designed and produced under such standards and regulations. It can be said that the Japanese trucks are comparatively simple in structure but are in a level equal to or higher than European and USA automobiles in respect of performance. Also in respect of the international harmonization, the internationalization of standards is being conducted in Japan on the basis of ISO and the internationalization for regulations is considered to be under preparation.

To reduce ultra fine particle number concentration from a heavy-duty diesel engine, the effects of diesel fuel property and after-treatment systems were studied. The reduction of ultra fine particle number concentration over steady state mode using an 8 liter turbocharged and after-cooled diesel engine was evaluated. PM size distribution was measured by a scanning mobility particle sizer (SMPS). The evaluation used a commercially available current diesel fuel (Sulfur Content: 0.0036 wt%), high sulfur diesel fuel (Sulfur Content: 0.046 wt%) and low sulfur diesel fuel (Sulfur Content: 0.007 wt%). The after-treatment systems were an oxidation catalyst, a wire-mesh type DPF (Diesel Particle Filter) and a wall-flow type catalyzed DPF. The results show that fine particle number concentration is reduced with a low sulfur fuel, an oxidation catalyst, a wire-mesh type DPF (Diesel Particulate Filter) and wall flow type catalyzed DPF, respectively.

To reduce NOx and Particulate Matter (PM) emissions from a heavy-duty diesel engine, the effects of urea selective catalytic reduction (SCR) systems were studied. Proto type urea SCR system was composed of NO oxidation catalyst, SCR catalyst and ammonia (NH3) reduction catalyst. The NOx reduction performance of urea SCR system was improved by a new zeolite type catalyst and mixer for urea distribution at the steady state operating conditions. NOx and PM reduction performance of the urea SCR system with DPF was evaluated over JE05 mode of Japan. The NOx reduction efficiency of the urea SCR catalyst system was 72% at JE05 mode. The PM reduction efficiency of the urea SCR catalyst system with DPF was 93% at JE05 mode. Several kinds of un-regulated matters were detected including NH3 and N2O leak from the exhaust gas. It is necessary to have further study for detailed measurements for un-regulated emissions from urea solution.

To reduce NOx emissions from a heavy-duty engine at low exhaust temperature conditions, the plasma-assisted SCR (Selective Catalytic Reduction) system was evaluated. The plasma-assisted SCR system is mainly composed of an ammonia gas supply system and a plasma reactor including a pellet type SCR catalyst. The preliminary test with simulated gases of diesel exhaust showed an improvement in the NOx reduction performance by means of the plasma-assisted SCR system, even below 150°C conditions. Furthermore, NOx reduction ratio was improved up to 77% at 110°C with increase in the catalyst volume. Also NOx emissions from a heavy-duty diesel engine over the transient test mode in Japan (JE05) were reduced by the plasma-assisted SCR system. However, unregulated emissions, e.g., aldehydes, were increased with the plasma environment. This paper reports the advantages and disadvantages of the plasma-assisted SCR system for a heavy-duty diesel engine.

A method of predictive simulation of flow-induced noise using computational fluid dynamics has been developed. The goal for the developed method was application in the vehicle development process, and the target of the research was therefore set as balancing the realization of a practical level of predictive accuracy and a practical computation time. In order to simulate flow-induced noise, it is necessary to compute detailed eddy flows and changes in the density of the air. In the research discussed in this paper, the occurrence or non-occurrence of flow-induced noise was predicted by conducting unsteady compressible flow calculation using large eddy simulation, a type of turbulence model. The target flow-induced noise for prediction was narrow-band noise, a type of noise in which sound increases in specific frequency ranges.

In recent years, emission regulations have become more stringent as a result of increased environmental awareness in each region of the world. For lean-burn diesel engines, since it is not possible to use three-way catalytic converters, reducing NOX emissions is a difficult technical challenge. To respond to these strict regulations, an exhaust gas aftertreatment system was developed, featuring a lean NOX catalyst (LNC) that uses a new chemical reaction mechanism to reduce NOX. The feature of the new LNC is the way it reduces NOX through an NH3-selective catalytic reduction (SCR), in which NOX adsorbed in the lean mixture condition is converted to NH3 in the rich mixture condition and reduced in the following lean mixture condition. Thus, the new system allows more efficient reduction of NOX than its conventional counterparts. However, an appropriate switching control between lean and rich mixture conditions along with compensation for catalyst deterioration was necessary.

In diesel engine trucks, the sound quality improvement as well as the noise level reduction is demanded because of their annoying exterior noise. The semantic differential method was applied to evaluate the sound quality of trucks. In order to improve the analytical accuracy, subjects who can evaluate the characteristics of sound quality were statistically selected among all the subjects. Comfortability and powerfulness were extracted as the principal components by using the data of the selected subjects. It has been clarified that the comfortability strongly relates to high frequency element ratio, high frequency level, etc. The powerfulness strongly relates to the Zwicker loudness.

In recent years, emission regulations have become more stringent as a result of increased environmental awareness in each region of the world. For diesel engines, reducing NOX emissions is a difficult technical challenge.[1],[2],[3],[4]. To respond to these strict regulations, an exhaust gas aftertreatment system was developed, featuring a lean NOX catalyst (LNC) that uses a new chemical reaction mechanism to reduce NOX. The feature of the new LNC is the way it reduces NOX through an NH3-selective catalytic reduction (SCR), in which NOX adsorbed in the lean mixture condition is converted to NH3 in the rich mixture condition and reduced in the following lean mixture condition. Thus, the new system allows the effective reduction of NOX. However, in order to realize cleaner emission gases, precise engine control in response to the state of the exhaust aftertreatment system is essential.

Lean-burn is an effective means of reducing CO2 emissions. To date, Homogenous Lean Charge Spark Ignition (HLSI) combustion, which lowers emissions of both CO2 and NOx, has been studied. Although HLSI realizes lower emission, it is a major challenge for lean-burn engines to meet SULEV regulations, so we have developed a new aftertreatment system for HLSI engines. It consists of three types of catalysts that have different functions, as well as special engine control methods. As the first stage in achieving SULEV emissions, this study focused on enhancing performance under lean conditions. HLSI engine exhaust gases contain high concentrations of hydrocarbons, including a large amount of paraffin, which are difficult to purify, rather than low concentrations of NOx. Therefore, the key point in low emissions is to purify not only NOx, but also high concentrations of paraffin at the same time.

This research sought to develop a dynamic charging system, achieving an unlimited EV cruising range by charging the EV at high power during cruising. This system would help make it possible to finish battery charging in a short time by contact with the EV while cruising and enable drivers to freely cruise their intended routes after charging. A simulation of dynamic charging conditions was conducted for ordinary autonomous cruising (i.e., ordinary EV cruising) when dynamically charging at a high power of 450-kW (DC 750 V, 600 A). This report discusses the study results of a method of building the infrastructure, as well as looking at the cruise test results and future outlook. In particular, the research clarified the conditions for achieving an unlimited vehicle cruising range with a 450-kW dynamic charging system. It also demonstrated that this system would allow battery capacities to be greatly reduced and make it possible to secure the battery supply volume and resources.

A 2-LEG NOx Storage-Reduction (NSR) catalyst system is one of potential after-treatment technology to meet stringent NOx and PM emissions standards as Post New Long Term (Japanese 2009 regulation) and US'10. Concerning NOx reduction using NSR catalyst, a secondary fuel injection is necessary to make fuel-rich exhaust condition during the NOx reduction, and causes its fuel penalty. Since fuel injected in the high-temperature (∼250 degrees Celsius) exhaust instantly reacts with oxygen in common diesel exhaust, the proportion of fuel consumption to reduce the NOx stored on NSR catalyst is relatively small. A 2-LEG NSR catalyst system has the decreasing exhaust flow mechanism during NOx reduction, and the potential to improve the NOx reduction and fuel penalty. Therefore, this paper studies the 2-LEG NSR catalyst system. The after-treatment system consists of NSR catalysts, a secondary fuel injection system, flow controlled valves and a Catalyzed Diesel Particulate Filter (CDPF).

A large-size truck is equipped with a variety of audible warning devices. These warning devices are grouped into three categories by their usage, i.e., malfunction type, proximity type and attention type. The sound characteristics of warning sound that are investigated for each type are signal envelope, fundamental frequency and the number of harmonics. Many sounds are synthesized with nine fundamental frequencies, ten or fewer harmonics and two signal envelopes. With volume fixed, these sounds are evaluated using an unpleasantness rating scale, and the functional impression of these sound is also chosen. From the results, the range of fundamental frequencies, the number of harmonics and the shapes of signal envelopes for preferable sound quality are determined.

Simulation was employed to estimate the fuel economy enhancement from the application of an exhaust heat recovery system using a thermoelectric generator (TEG) in a series hybrid. The properties of the thermoelectric elements were obtained by self-assessment and set as the conditions for estimating the fuel economy. It was concluded that applying exhaust system insulation and forming the appropriate combination of elements with differing temperature properties inside the TEG could yield an enhancement of about 3% in fuel economy. An actual vehicle was also used to verify the calculation elements in the fuel economy simulation, and their reliability was confirmed.

Conventionally, the Ni-based superalloys NCF3015 (30Ni-15Cr) and the high nickel content NCF440 (70Ni-19Cr) (with its outstanding wear resistance and corrosion resistance), have been used as engine exhaust valve materials. In recent years, automobile exhaust gases have become hotter because of exhaust gas regulations and enhanced fuel consumption efficiency. Resource conservation and cost reductions also factor into global environmental challenges. To meet these requirements, NCF5015 (50Ni-15Cr), a new resource-conserving, low-cost Ni-based heat-resistant alloy with similar high-temperature strength and wear resistance as NCF440, has been developed. NCF5015's ability to simultaneously provide wear resistance, corrosion resistance and strength when NCF5015 is used with diesel engines was verified and the material was then used in exhaust valves.

At present, measurements of running resistance are conducted outdoors as a matter of course. Because of this, the ambient temperature at the time of the measurements has a considerable impact on the measurement data. The research discussed in this paper focused on the temperature characteristic of the tires and developed a new correction technique using a special rolling test apparatus. Specifically, using a tire rolling test apparatus that made it possible to vary the ambient temperature, measurements were conducted while varying the levels of factors other than temperature that affect rolling resistance (load, inflation pressure, and speed). Next, a regression analysis was applied to the data for each factor, and coefficients for a relational expression were derived, making it possible to derive a quadratic equation for the tire rolling resistance correction formula.

High viscosity index(HVI) petroleum base stock, with excellent temperature-viscosity characteristics, oxidation resistance, and low-evaporation properties, offers advantages as the base stock for high fuel economy engine oils, particularly because of its low-friction properties in the boundary and/or “E.H.L (Elastohydrodynamic Lubrication)” area due to its rheological characteristics. This research evaluated HVI base stock's low-friction properties. Upgrading the oil from 5W-30 to 5W-20 was also investigated. The friction properties of the HVI base stock were measured by a unit friction platform. The results show a 28% reduction in friction coefficient compared with the conventional, solvent refined oil, which is attributable to the high-pressure viscosity of the base oil.

1 A new surface modification heat treatment technology called Wonder Process Craft which is different from plating and coating, was applied to the skirt section, which is the sliding surface of the piston in an internal combustion engine. This was intended to improve fuel economy and mechanical characteristics by reducing sliding resistance. In the application of solid lubrication, this treatment does not require the usage of binder, which was necessary for conventional coating, leading to the highest level achievable for the low sliding resistance effect inherent of solid lubrication. Since this treatment does not involve any change in significant dimensions, shapes, surface roughness, and so on, applying this treatment is easy. The persistence of the effect, productivity and recyclability of waste and emissions during treatment were also taken into account.

The effects of aerodynamic coefficients on handling response and flat ride were quantified. For handling response, the aerodynamic effect was quantified by analysis with linear representation and a two-wheel simulation model, using aerodynamic coefficients obtained from a full scale car wind tunnel. The correlation of aerodynamic coefficients and handling response with driving feel was also ascertained. Aerodynamic yaw moment and side-force were also converted to equivalent front and rear lift to standardize aerodynamic indexes and improve aerodynamic development efficiency. For flat ride, steady and unsteady aerodynamic effects were quantified by analysis with a two-degree-of-freedom mass-spring-damper simulation model and aerodynamic coefficients obtained from a 35% scale model wind tunnel and towing tank test. Unsteady aerodynamic force occurrence mechanism was ascertained by unsteady CFD using dynamic mesh.