To satisfy real driving emissions (RDE) regulations, it is necessary to reduce exhausted gas emissions under all engine operating conditions. This report examines the potential of gas-to-liquid (GTL) emulsified fuel in terms of exhausted gas emissions and fuel efficiency. Experiments using a single-cylinder diesel engine found that GTL-emulsion fuel drastically reduced NOx and smoke emissions at high loads, while also improving fuel efficiency. Furthermore, by visualizing the spray combustion process in a constant volume chamber, this research also confirmed that GTL-emulsion fuel achieves a soot-less flame even in diffusive combustion.

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Hydrogen concentration in diesel exhaust gas was measured on engine test bench by using hydrogen sensor of solid electrolyte ceramics which can measure only hydrogen selectively by proton conduction, which enables measurement of hydrogen concentration in situ and continuously. In this study, the hydrogen concentration found to be different from that of measured DOC in front and behind. In addition, we also measured hydrogen concentration changes under loaded state and idle state.

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Urea SCR on Diesel Particulate Filter (SCR/DPF) is important technology for reduction of NOx and PM, and is required to meet the emission and fuel economy standards which are becoming more stringent in the future. However, the SCR/DPF catalyst performance deteriorates due to exposure in severe environment. In this study, to investigate the catalyst degradation mechanism, we focused on hydrothermal degradation among many factors of the SCR/DPF degradation. Several hydrothermal aging conditions were selected. NOx reaction, NH₃ and NO oxidation rates were measured and amount of ion-exchanged Cu and ionexchangeable sites were determined by H₂-TPR and ²⁹Si NMR, respectively. We found that NOx reaction rate increased with increasing the amount of ion-exchanged Cu. At the test temperature of 400°C and over, no correlation was found between the NOx reaction rate and the amount of ion-exchanged Cu. Under the temperature conditions of 300°C or less where the diffusion has no influence on the NOx reaction rate, NOx reaction rate is proportional to the amount of ion-exchanged Cu.

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Laser-induced breakdown spectroscopy (LIBS) has been applied to measure local air-fuel ratio (equivalence ratio) in combustion. However, the research about luminous flame has not been reported. In this study, using a counterflow diffusion luminous flame (Propane-Air), LIBS spectra were observed at various measurement points with various equivalence ratios in the luminous flame (Φ<8). The equivalence ratios of those measurement points are estimated with corresponding CHEMKIN calculations. The relationship between the calculated equivalence ratios and the measured emission intensity ratios (CN_385nm/H_656nm, CN_385nm/O_777nm, H_656nm/O_777nm) are investigated. The results demonstrate that LIBS measurements of local equivalence ratio may be feasible even in the luminous flame.

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To investigate the effect of exhaust gas recirculation (EGR) on ignition characteristics of gasoline surrogate, ignition delay times of gasoline surrogate mixtures, S5H, consisting of n-heptane, isooctane, toluene, diisobutylene, and methylcyclohexane were measured using a rapid compression machine under the EGR conditions at the pressure of 2 MPa and 4 MPa, at 720 K, and an equivalence ratio of 0.5. Ignition delay times were also calculated using a detailed chemical kinetic model of gasoline surrogate mixtures. Ignition delay times of S5H under the EGR condition were longer than those of S5H without EGR gas. The most contributory factor under the EGR conditions was investigated using the experimental and calculated results. As a result, it is found that the reduction of fuel concentration in the initial gas mixtures had the strongest influence on the ignition characteristics of gasoline surrogate among the various factors under the EGR conditions.

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Polycyclic aromatic hydrocarbons (PAHs) are itself exhibit carcinogenicity and believed to be precursors of the particulate matter. In this study, measurements of the particle volume fraction (PVF) and the mole fractions of PAHs were carried out for counter flow diffusion flames of iso-Octane and Toluene reference fuels. PAHs are measured by using the Thermal Desorption - Gas Chromatography / Mass Spectrometry system. Experimental results were compared with numerical results calculated by using the KAUST 1 model, the CRECK model and the P.AN model. In this paper, oxidation and decomposition reactions of Benzo [e] Pyrene, Benzo [ghi] Perylene, Coronene and Perylene were added into the KAUST 1 model. As results, it was shown that the CRECK model shows good reproducibility of PVF and PAHs mole fraction profiles. Although the KAUST 1 model shows differences in PVF profiles, there is room for improvement by adjusting the surface reactions. Since the KAUST 1 model is extremely smaller than the CRECK model, it can be thought of as a model suitable for engine simulations.

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We computed the primary soot particles generation in a shock tube pyrolysis with toluene/n-heptane and toluene/iso-octane mixtures by Alexiou et al. Calculated soot yield using latest elementary reaction model was exceeded the experimental one. It is assumed that nucleation reactions and acetylene addition reaction were the primary factors. Because those chemical reaction rates have some uncertainty, the soot generation characteristics were investigated by changing the chemical reaction rates of nucleation reactions and acetylene addition reaction.

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Direct injection gasoline engine has higher thermal efficiency than conventional port fuel injection gasoline engine. However, it is necessary to make the air-fuel mixture in a short time and it is difficult to control the air-fuel mixture. Therefore, in order to elucidate the liquid phase and the vapor phase of gasoline spray in the air-fuel mixture formation process, the visualization of spray and analysis was carried out by using the LIEF method.

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In order to reduce particulate matter (PM) emitted from a gasoline direct injection spark ignition (DISI) engine, it is important to reduce the fuel film deposition on the wall and the local rich air-fuel mixture formation. As a means to reduce these, the high pressure fuel injection is considered to be effective. In this study, we evaluated the influence of increasing fuel injection pressure to PM emission with using the glass cylinder engine at fast idle operation. The fuel film deposition on the piston was measured by using ultraviolet irradiation to cause excited fluorescence in the fuel which contained the fluorescent agent. And, the fuel liquid and vapor phase was measured by using Laser Induced Exciplex Fluorescence (LIEF) method. The number of PM from a DISI engine was decreased by increasing fuel pressure from 20MPa to 80MPa. The fuel film deposition on the piston was decreased by increasing the pressure. The area of the liquid phase inside the combustion chamber was reduced, and the variation of vapor phase was decreased by increasing the fuel pressure.

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This study describes the engine combustion characteristics of the gasoline surrogate fuels for Japanese market fuel, which has been studied by Gasoline Combustion Team in Cross-ministerial Strategic Innovation Promotion Program (SIP) Innovative Combustion Technology. Lean combustion characteristics and anti-knocking quality of those surrogate fuels which are consisted of 3 and 5 components show good agreement with regular and premium gasoline in Japanese market. The analysis with detailed reaction mechanism developed in the gasoline team on knocking has been conducted. The results are also introduced.

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Reducing the surface roughness of a cylinder bore is effective for reducing friction forces, but it is also known that too smooth surface sometimes causes scuffing. The test method for piston / cylinder friction in engine starting was shown in this paper. Friction force under the steady operating condition was also measured using a mono-cylinder diesel engine by means of floating liner method. The smooth surface made by electrolytic polishing showed low friction under the steady operating conditions forces but high friction peak was founded at the firing top dead center under the higher load condition in engine starting. It was assumed that the smooth cylinder had a disadvantage for scuffing under oil-starved conditions.

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When using a conventional oil pump, excess oil pressure caused by oil temperature occurs. We focused on this excess oil pressure region, and extended our development. We developed a temperature sensitive variable oil pump, by placing a temperature sensitive relief mechanism parallelly with the conventional relief mechanism. By using the wax characteristics to control the relief amount by oil temperature, we achieve requested oil pressure while reducing excess oil pressure caused by oil temperature, thus contributing to fuel efficiency improvement.

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Gasoline direct injection (DI) has been widely applied to high-compression-ratio engines for better thermal efficiency. The reduction of particulate number (PN) emissions is the major concern of a gasoline DI engine due to the introduction of PN standards in Euro 6 emission regulations. PN emissions during the catalyst-warm-up operation are substantially high. Therefore, it is important to focus on combustion characteristics during this operation. This paper describes an investigation to understand the mechanisms of particulate formation using optical engine measurements and CFD simulations. As a result, the soot formation caused by pool fire on the piston surface was considered to be a main source of PN emissions. Then, to evaluate the amount of soot quantitatively, the two-color method was conducted and the amount of soot was quantified by KL factor. It was found that PN emissions were strongly correlated with KL factor. To reduct PN emissions, the injection strategy was optimized. 70% decreasing of KL factor is achieved at the optical engine during the catalyst-warm-up operation and the vehicle PN emissions during the NEDC is reduced by 66%.

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A comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometer (GC x GC - TOFMS) was used for analysis of gas composition in a constant volume combustion chamber before ignition. For mass spectrometer, electron ionization and field ionization were used in order to estimate molecular formula and identify chemical compounds. Reaction intermediates produced from n-C₇H₁₆/O₂/Ar mixture were analyzed in this study. About oxygen-containing hydrocarbons, it was suggested that the concentration of reaction products from φ=5.0 were more than 10 times as high as in comparison with those of φ=1.0.

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The purpose of this report is to grasp the entrainment characteristics in diesel sprays. Here, shadowgraph photography, scattered light photography and analysis of free spray in noncombustible field was carried out by using a constant volume vessel. As the result of measurement using shadowgraph photography and scattered light photography, it was found that spray volume is larger with the rise of fuel injection pressure, and spray volume of evaporation field is larger than that of non evaporation field.

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Plug-in hybrid vehicles (PHVs) have two driving modes, which are known as charge-depleting (CD) mode and charge-sustaining (CS) mode. The environmental performance of a PHV differs based on the distance between the start and end in the case of a trip in which the PHV switches from CD mode to CS mode. This paper focuses on the low-carbon effect and energy cost reduction effect of PHVs and numerically describes the dependence of these effects on the distance traveled. It also reports new knowledge obtained through a detailed analysis and examination of the equations.

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High quality vehicle dynamic performances considering human sensitivity, such as "a motion just as intended by a driver", are required recently, and this should be designed in closed-loop driving situation. However, existing studies about the performance aren’t enough, and real vehicle engineering is still relying on open-loop index design and driver’s sensory evaluation. In this study, a new hypothesis for the vehicle dynamics characteristics which could realize the performance will be proposed, using the driver's steering operation mechanism analysis in closed-loop situation. Results of verification with a driving simulator, including the measurement of driver's brain activities, will be introduced.

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The haptic guidance steering control is a driver assist system to supply small torque to the steering wheel to follow the target trajectory, which is calculated based on the PD control with the feedback of the error between the target trajectory and the look-ahead position. The change of the look-ahead position according to the radius of the curve is measured and the performance of the haptic guidance control considering the change of the look ahead position is examined through the driving simulator experiments. The results indicated the adjusting the look-ahead position improves the stability of the vehicle.

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To obtain sufficient accuracy for vehicle dynamic performance simulation, it is necessary to consider bushing amplitude and frequency dependency as well as preload effects in the rubber bushing model. FE models are capable of reproducing these characteristics though it is difficult to obtain sufficient calculation accuracy within practical computation time. This paper proposes a new low degree of freedom (DOF) bushing model. The new bushing model exhibits high computational performance while maintaining precision.

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This paper presents an analysis of the crossing accidents caused by four-wheeled vehicles to each other at an intersection from a quantitative point of view using a detailed accident data. Based on the position of the roadside object and the danger perception speed, the database such as a grazing angle to another vehicle or the calculated perception distance were created, and it could reveal the various feature of crossing accidents. Furthermore, when reviewing the collision avoidance effect using the automatic braking, it was found that the detection angle of the sensor is as important as the relative position to another vehicle.

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Vehicle localization based on matching between on-vehicle camera images and high-precision map has been developed for automated driving. We propose a method to associate a map with images by stochastically generating a white line section corresponding to appearance from white line types. Moreover, we propose a robust method by estimating not only the latest location but also the trajectory of the vehicle. The proposed method was tested in Shuto expressway, and the vehicle position was identified with sub-meter accuracy.

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A muscle controller with two feedback controls for posture and reaction forces imparted at a steering wheel and pedals was developed for more accurate predictions of relaxed- and tensed-occupant kinematics in pre-crash or low-speed frontal crash situations. We applied the muscle controller to a human body finite element model with whole-body muscles called THUMS version 5, and predicted occupant kinematics in a pre-crash event with autonomous emergency brakes. Simulation results with posture control and total control of posture and reaction forces showed similar tendency for relaxed- and tensed-volunteer data obtained from the literature, respectively.

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To safely move from its fire accident site a hydrogen fuel cell vehicle equipped with a carbon fiber reinforced plastic composite cylinder for compressed hydrogen (CFRP cylinder) and to safely scrap the burnt vehicle, it is necessary to verify whether the thermally-activated pressure relief device (TPRD) of the CFRP cylinder has already been activated, releasing the hydrogen gas from the cylinder. To develop a simple post-fire verification method on TPRD activation, the present study was conducted on the simple technique of verifying TPRD activation by measuring hydrogen concentration at the TPRD gas release port, using the hydrogen densitometers and TypeIII and TypeIV CFRP cylinders having different linings. As a result, TPRD activation status can be determined by measuring gas concentration with a catalytic combustion hydrogen densitometer at the cylinder’s TPRD gas release port within 24 hours.

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In current Japan, almost freighting is carried by truckload transportation. So, trucks are indispensable vehicles for logistics. Therefore, it is important to construct occupants’ safety in trucks. By improving technologies for preventive safety, many type preventive safety devices are equipped on trucks. However, it is impossible to cover all round safety by preventive safety technologies. Therefore it is important to consider occupants’ crash safety. For constructing occupants’ crash safety, it is necessary to understand detailed occupants’ injury speciation in collision accident. From previous days, there are many researches or investigations reported for occupants’ injury in passenger vehicle collisions. However there are few reports for large class vehicle collisions as trucks or buses. In the present study, the author focuses attention on collisions between heavy duty trucks and investigates to clarify injury speciation of occupants in heavy duty trucks collided by frontal collision or rear end collision, by using traffic accident integrated data stored in ITARDA (Institute for Traffic Accident Research and Data Analysis). Detailed occupants’ injury speciation by body region is clarified from a view-point of statistical accident analysis..

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Our research goal is to provide “fun” for drivers as a reward for safe driving, and to encourage spontaneous safe driving. An expressway driving game, which encourages drivers to keep the speed limit spontaneously, was proposed in our previous study. The present manuscript discusses the effectiveness of the game on driver behavior by using dozens of normal drivers’ data. The results revealed that many drivers felt fun for the game, and the game could provoke spontaneous behavioral change of keeping the speed limit.

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Experimental and theoretical study of a liquid leak and gaseous a leak under high pressure was conducted in this paper. It is shown that the leak flow rate of the liquid increases in proportion to the pressure, and that of the gas increases square by the pressure in the leak path more than 1 micron in diameter and that increases in proportion to the pressure in the leak path less than 1 micron in diameter. And it is found that the liquid leak path transit time is within 0.1 seconds then it does not influence the inspection time.

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Automotive thermal environment is modeled to design climate control logics based on thermal sensation. A proposed model can perform dynamical simulation of thermal sensation and energy consumption on a vehicle with HVAC and auxiliary thermal devices (a seat heater, a steering wheel heater, etc.), and it provides the development of cooperative control logics.

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This study aims at evaluating economic and environmental benefits of Solar Hybrid Vehicle (SHV) by comparing other types of vehicle, such as internal combustion engine vehicle, hybrid vehicle, plug-in hybrid vehicle (PHV) and battery electric vehicle. Three different types of SHVs (SHVS, SHVM and SHVL) with varying photovoltaic panel (PV) size and battery were considered. The settings of cost and energy efficiency of each vehicle are based on assumed technology level in 2030. Our findings suggest PHVs to be the most cost effective option for the reduction of CO₂ emissions. Next to PHVs, SHVs were evaluated as one of the most cost-effective vehicles among a wide range of users for the reduction of CO₂ emissions.

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Inductively coupled plasma mass spectrometry (ICP-MS) is widely used when rapid and sensitive detection for a wide range of elements of airborne particles is required in many situations, such as the monitoring of the ambient particulate matter (PM), emission sources, and the clean room air for semiconductor manufacture processes. For on-line and real-time analysis of aerosol samples using ICP-MS, the gas exchange devices (GED) which followed by the replacement of air with argon and transported to the ICP-MS is need to be equipped due to sustaining the plasma. However, the ICP-MS used a quadrupole mass spectrometer (ICP-QMS), a detailed study on the signal fine structure with scanning-based mass spectrometers but no simultaneous multi-element measurement was possible. In order to further improve time resolution of the ICP-QMS and to extend its capabilities to determine single particle information, ICP-MS equipped with the Time-of-Flight Mass Spectrometer (ICP-TOFMS) was developed recently. This study presents for application of real-time measurement for elements in particles using ICP-TOFMS. This technique is allowed to detect of engine oil additive elements in gasoline vehicle exhaust particles.

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High strength steels have been applied to the automobile body as a means to reduce weight and improve crash safety performance. In order to satisfy press formability and part performance, improvement of material properties was required. Studies of press forming and crash performance showed the lambda value, or hole expansion ratio, to be especially important for improving formability and part performance. Application to body components, that could not achieved with conventional steels, was realized by the development of the new high strength steel sheet with high elongation and high local ductility

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In this paper, an autonomous lane change method using nonlinear model predictive control and graph theory is proposed. By using graph theory, a safe driving path considering traffic conditions of other vehicles is calculated. By using that path, a trajectory and velocity considering comfort are calculated using nonlinear model predictive control. Simulation results show that behaviors to overtake other vehicles traveling ahead and to give way to other vehicles traveling behind are obtained. Moreover, simulation result indicates that the proposed method can be calculated about ten times faster than the conventional method using dynamic programming.

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