In newly proposed ignition-combustion concept named PCC (Plume Ignition Combustion Concept) further reduction in NOx formation is investigated in this study by modifying injected hydrogen jet conditions. One used is cross hole nozzle having two φ1.6 holes which are designed to collapse in the region of spark plug tip in order to promote entrainment of air to hydrogen jet and generate high turbulence in the hydrogen plume. The other is parallel multi hole nozzle having five φ1.3 holes which are designed to offer parallel jets to spark plug in order to supply non-spreading multi jets. As a result, cross hole nozzle was effective to entrain air to H2 jet. Parallel hole nozzle was effective to concentrate H2 in the vicinity of spark plug tip compared with conventionally used non-parallel 9 hole nozzle.

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The combustion concept reported in the first report needs fine atomization and low penetration spray. The new nozzle for both demands is applied new technology, based on a slit nozzle. First, the shortening of nozzle hole length to utilize flow turbulence generated at nozzle hole inlet. Second, the installation of the projection shape on the needle tip as the rectifier to control the vortex in sac. In addition to the foregoing items for lower penetration , angle of nozzle hole is enlarged to reinforce spray momentum dispersion. As stated above, the developing nozzle which is improved by the based on inside nozzle flow has achieved the spray performance which can adapt to the new concept and engine performance target.

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In direct-injection spark-ignition engines, PM tends to be emitted caused by poor evaporation and combustion of fuel sprays impinging on the combustion chamber wall. An experimental study was carried out to visualize such phenomena at temperatures and pressures reproduced in a constant volume chamber. The results show that ambient and wall temperatures are major factors influencing the amount of fuel film attached on the wall, its evaporation and combustion and PM formation. A numerical simulation model has been developed to predict the processes of fuel film formed on the wall and its evaporation on.

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For a wide detection range of soot mass concentration and fast response, a laser smoke meter based on light scattering and light extinction was developed. A common rail, turbo-charged diesel engine was used in calibration of soot mass concentration measurements. As a result, the laser smoke meter was found to have a minimum detection sensitivity of 0.01mg/m³. The practical calibration of the light scattering mode which is applied to low soot concentration measurements was carried out using the light extinction method. Continuous measurements of a wide range of 0.01-1000mg/m³ were performed by combination of extinction and scattering methods.

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In this work, ethanol port injection was used in a diesel engine as a strategy to extend engine load range while simultaneously reducing NOx and Soot. The engine performance was investigated under high intake boost with different ethanol and EGR ratios. It was found that ethanol port injection increased the load limitation by about 50% compared to diesel low temperature combustion at intake boost of 1.0 bar gauge. When intake boost of 1.5 bar gauge and ethanol ratio of 83% by total fuel energy was used, 16 bar IMEP was achieved successfully with less than 0.2 g/(kW·h) NOx and 0.01 g/(kW·h) Soot.

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HCCI engines have attracted widespread attention as high-efficiency and low-pollution combustion systems. The authors have conducted experiments to visualize rapid combustion in the cylinder accompanied by cylinder pressure oscillations and have also investigated the factors influencing rapid combustion in HCCI engines. The results have shown that in combustion accompanied by cylinder pressure oscillations a highly brilliant flame occurs simultaneously over a wide area of the combustion chamber almost instantaneously. It has also been found that the rapidity of HCCI combustion is influenced by the ignition timing and the quantity of heat produced per cycle by the injected fuel.

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In order to utilize bio-butanol as an alternative diesel fuel, three blend fuels of gas oil and butanol isomers (1-butanol, 2-butanol and isobutanol) were investigated using a single cylinder DI diesel engine for the ignitability, combustion characteristics and exhaust emissions. For the three blends, butanol content is 40 mass%. The experimental result shows that in order of 1-butanol/gas oil, 2-butanol/gas oil and isobutanol/gas oil the ignition delay becomes longer and the HC and CO emissions increase at low load.

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For direct-injection gasoline engines, reducing fuel consumption and particulate number in exhaust gas are needed. Reducing particulate number can be achieved by reducing the fuel adhesion to a cylinder and piston surface, and by injecting fuel multiple times which increases homogeneity degree of fuel-air mixture. For this purpose, reducing the minimum injection quantity is required. We developed the simulator which can analyze behavior of the valve and the injection characteristics, by taking a non-steady electromagnetic field analysis and the flow analysis in an equation of motion, and taking into account of the detailed of structure of the injector. We clarified that the valve bouncing during the opening action and residual magnetic force causes an increase of the minimum injection quantity.

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A comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometer (GC x GC - TOFMS) was employed to analyze combustion products in exhaust gas emitted by SI combustion using n-heptane as fuel and poly-α-olefin as lubricating oil. For identification of detected substance, NIST library search of the GC Image software was used. In this study, it was suggested that branched chain compounds, aromatic compounds and naphthenic compounds existed in exhaust gas of n-heptane SI combustion, in spite of only using straight chain hydrocarbons. In addition to that, the existence of many types of nitrogen-containing or oxygen-containing hydrocarbons was suggested.

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Since the engine combustion is affected by various engine parameters as well as fuel characteristics, it is very difficult to find out the clear effect of fuel property on it. In order to clarify the change of emission characteristic caused by fuel trend, we propose a fundamental flame research method using a small pool flame system. Characteristics of PM exhausted from laminar diffusion flames of gasoline and surrogate fuels were investigated by SMPS (Scanning Mobility Particle Sizer), LPI (Low Pressure Impactor) and combustion type PM analyzer. PM exhausted from flames of various chemical structures such as iso-alkane, cyclo-alkane, olefin and aromatic were also investigated. As the result, it was found that the exhaust-PM concentration and PM size increased with increasing of toluene concentration.

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Charge Stratification has been thought as one of the ways to avoid the sharp pressure rises of HCCI combustion. The purpose of this study is to evaluate the potential of equivalence ratio, initial temperature, and EGR Stratifications to reduce Pressure Rise Rate on HCCI combustion. Pre-mixture with stratifications is charged into Rapid Compression Machine. After that, the pre-mixture is compressed and in that process, in-cylinder gas pressure and temperature are analyzed. Additionally numerical calculation with multi-zones model is run to know the potential of equivalence ratio, initial temperature, and EGR stratifications for reducing Pressure Rise Rate. This study investigates to expect the degree of stratification of in-cylinder charge shown in real engine from single-zone model. For clearly verifying the degree of stratification of in-cylinder charge, the results from single-zone model are compared with those from multi-zone model. The considered types of stratification of in-cylinder charge are thermal stratification, fuel stratification and EGR stratification. The comparison results between single-zone model and multi-zone model show that EGR stratification was most effective to disperse ignition timing compared to the thermal stratification and fuel stratification when setting the same time differences of ignition timing shown in single-zone model. Among the results from three type of stratification of in-cylinder charge, fuel stratification was the worst on disperse of ignition timing.

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New metal V belt CVT is developed to contribute to the best fuel economy in the vehicle category. This CVT features as follows, 1.Highly transmission efficiency and the best fuel economy. 2. Improvement of belt noise. 3. Advancement of drivability performance.

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We developed a compact, low-cost and simple hydraulic hybrid system. This system has regeneration state, assist state and engine start-stop function state. These states are controlled by an oil circuit with spool valve and electric linear solenoid. We developed two important components, a gear pump/motor that works as both pump and motor with high efficiency and a low-flow force spool valve with pressure control groove. We applied this technology to a small car and achieved smooth regeneration/assist, low noise and quick engine restart by cooperative engine control. This system improves vehicle fuel economy 10.1% in Japanese JC08 mode.

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This paper presents the effect of body roll on vehicle dynamic characteristics. The stability of vehicle motion inclusive of body roll is examined using the simplified vehicle model. As a result, it is understood that the vehicle motion which has under steer characteristics by using roll steer becomes oscillatory and unstable. Analytical solution of roll steer coefficient and stability limit speed is shown. Moreover, the detailed analysis of vehicle motion that is studied by using root locus is also shown.

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The effect of roll axis height to ride comfort is analyzed by full vehicle model simulation. When vehicle runs on trumping road, the tires vibrate from side to side and up and down. This lead sprung mass to generate acceleration which degenerate ride comfort. The phenomenon is related to roll axis height. The each model with various roll axis height (0m to 1.2m) runs on the same trumping road. The generated acceleration of sprung mass is investigated to analyze the effect of roll axis height.

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This paper deals with analysis for absorption characteristics of porous media in automotive cabin. Elements of porous media are modeled by 3D finite elements, which have complex density and complex volume elasticity. By expanding the solution of complex eigenvalue problem with small parameter, equations of motion are derived using first order of asymptotic components. Modal loss factors are derived in material loss factors, share of strain energy of each element to total strain energy, damping effect concerning hysteresis and share of kinetic energy of each element to total kinetic energy.

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The small electric vehicle which is mounted “in-wheel motor” as one of the solutions of the single-passenger car is shown. Driver’s operating performance on driving vehicle is limited in emergency conditions. Therefore, it is important to set up active safety technology geared to the collision avoidance is based in the micro-car, especially. One measure to reduce accidents is an automatic collision avoidance system using automatic steering control. This research proposes an automatic steering system for collision avoidance by a steered vehicle called the ‘Active Torque Steering system (ATS)’. The purpose of this research is to clarify the automatic steering ability of the ATS vehicle by comparing it with that of an AFS function (Active Front Steering function) and a DYC function (Direct Yaw moment Control function) through simulations using the time history response and tire forces evaluation.

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Applying performance evaluation and optimization assisted by CAE to the structural design of car bodies and etc is becoming a universal procedure. In this study, an elasto-plastic material model appropriate for describing the work hardening properties of a metal material led by iron and steel was introduced into the topology optimization algorithm. And, optimization in crashworthiness of thin-walled steel structures was exemplified in numerical calculation. In addition, potentiality was revealed for application to the optimization of material arrangement potentiality as well as the topology optimization of structures.

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This study examines an automatic collision avoidance system for multi-articulated vehicles by steering control. The Model Predictive Control (MPC) is applied to the steering control with constraint on the relative yawing angle between the tractor and the second trailer to prevent rollover and jackknife in emergency avoidance. The MPC improves obstacle avoidance performance in comparison with the Liner Quadratic (LQ) controller. The controller with constraints on not only the relative yawing angle but also the steering angle suppresses the large steering angle input. The improved avoidance performance by the MPC is also confirmed with a detailed full vehicle model.

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We investigated the difference of severity between belted and unbelted patients in several types of collisions in our emergency room. In frontal collision, mortality and the severity of whole body were significantly higher in unbelted than in belted. In near-side collision, mortality and the severity of head/neck, face were significantly higher in unbelted than in belted. In far-side collision, mortality and the severity of head/neck, face, chest were significantly higher in unbelted than in belted. In rear end collision, the severity of chest was significantly higher in unbelted than in belted. Seatbelt use was effective in all types of collisions to prevent severe injury.

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Micro mobility, which is expected as new mobility for elder people, is studied in this paper. Micro mobility has two categories which are personal mobility and two seaters mobility. In Japan, personal mobility is called mini-car. In this paper, mini-car accidents using traffic accident data are analyzed.

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Injury risks in some impact modes are analyzed in relation to impact velocity, in order to offer the reference data to set up the boundary impact speed of the Severity Criteria of “Automobile Safety Integrated Level” in the functional safety standard ISO26262. These analyses were mainly conducted for the impact modes or conditions which were not able to be found after the literature review． NASS-CDS and NASS-PDCS data in United States and the ITARDA statistical data in Japan are used for these analyses.

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This study analyzes driver’s following characteristics with a pre-preceding vehicle in front of a preceding vehicle. Driving simulator experiments are examined with several subjects who are required to follow the preceding vehicle with/without the visible pre-preceding vehicle. The multiple regression analysis is applied to identify which information the driver uses to follow the vehicles. Experimental results show the subjects follow the preceding vehicle with information not only on the following vehicle but also on the pre-preceding vehicle.

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This paper describes relationships between aerodynamic drag on 1/4-scale car model and the vortices behind the car model. Large Eddy Simulation (LES) and wind tunnel test were conducted using the car model. The computational fluid dynamics (CFD) results were validated with wind tunnel test results and showed good correlations with static pressure on car model and streamwise velocity in the wake. The CFD results showed that there is a ring-shaped vortex behind the car. The results also showed that the circulation of the vortex ring and the distance between the vortex ring and car model have a strong correlation with the aerodynamic drag on the car model.

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A defogger is a system to remove dew condensation from windshield of an automobile. The defogger is indispensable for passenger’s safety since the dew on the windshield makes driver’s visibility worse, whereas it consumes large amount of energy, hence it is required to optimize energy performance of the defogger. To discuss the analytical design of the effective defogger, it is necessary to study the measurement method and the dynamical model for the dew condensation. In this paper, we propose the new measurement method based on image processing and the dynamical model for the dew condensation.

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High-strength steels are increasingly used in automobiles as a means of reducing auto body weight. However, in many cases, deterioration of dimensional accuracy is a problem. In particular, the increased springback of high-strength steels is a problem when press-forming parts. As a fundamental study, the relationship between springback and residual folds in formed parts was examined by experiments and calculation. In the actual manufacturing process, parts are formed in multiple steps, and the fold remaining in the work after bending must be flattened. While folds in mild steel are easily flattened using a flat die, it is difficult to flatten folds in high-strength steel using the same die. Although this is one cause of poor dimensional accuracy, little research has examined the problem of residual folds. In this study, two methods of flattening folds were examined by experiments and CAE, and a five-point reverse bending method was proposed. The results showed that flattening with a flat tool is insufficient to eliminate the fold in high-strength steel, but in contrast, a fold in a 980MPa high-strength steel sheet was completely flattened by five-point reverse bending.

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This Study proposes a method of state estimation and guidance-controlling of a vehicle using roadside LRF (Laser Range Finder). The proposed method extracts a vehicle from range points acquired from roadside LRF and estimates the vehicle's state. Moreover, the proposed method calculates vehicle control orders based on state of the vehicle and sends it to the vehicle using radio communication. Experimental results described in this paper show that a vehicle is controlled only by control order from roadside LRF.

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Intra-body communication technology is classified in two kinds. It is the current method and the electric field method. The electric field method is mainstream recently because applied range is wide. The electric field method is further subdivided. It is classified by the technical degree of difficulty. But, it is not known generally. Because, it was the secret matter in the business. We think that it is one of cause disturbing spread of intra-body communication technology. Therefore we explain classification of the electric field method intra-body communication technology on this paper. In addition, we explain the application to automobile of this communication technology.

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Recently, natural disaster has been occurring all over the world; Hurricane Katrina in Florida, Flooding in Thailand, and Tsunami on 3/11/2011 on north-east coast of Japan are those of significance. Large number of vehicles were submerged in those disaster (for example: 230,000 vehicles in 3/11 disaster). Although several experimental based vehicle submerging had been studied, the theory and mechanical analysis of vehicle submerging have not be seen. We have challenged to make a surrogate test since immediately after 3/11/2011. In this paper, the fundamental theory and mechanism of vehicle submerging is explained by a simulation based mechanical modeling and surrogate test, and it is verified by actual submerging experiments. It is clarified that the size of water passing area is the main cause of vehicle submerging.

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