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If a compressed hydrogen tank for vehicles is filled with hydrogen gas more quickly, the gas temperature in the tank will increase. In this study, we conducted hydrogen gas filling tests using the TYPE 3 and TYPE 4 tanks. During the tests, we measured the temperature of the internal liner surface and investigated its relationship with the gas temperature in the tank. We found that the gas temperature in the upper portion of the TYPE 4 tank rose locally during filling and that the temperature of the internal liner surface near that area also rose, resulting in a temperature higher than the gas temperature at the center of the tank. To keep the maximum temperature in the tank below the designed temperature (85°C) during filling and examine the representative tank internal temperatures, it is important to examine filling methods that can suppress local rises of tank internal temperature.

Aldehydes and ketones are known as one of the hazardous air pollutants. Usually, acidified 2,4-dinitrophenylhydrazine (DNPH) solution, or DNPH-impregnated cartridges are used for automotive exhaust carbonyls collection. Then, aldehydes and ketones combined with DNPH are analyzed by HPLC/UV (High Performance Liquid Chromatography/ Ultra Violet Detection). DNPH cartridge is used widely for a good point of the handling although handling of DNPH solution is not so convienient. However, the analytical result of acrolein using DNPH cartridge was known as the low reliability. Acrolein-DNPH is changed to acrolein-DNPH-DNPH in the cartridge with acid atmosphere before extraction. And then, acrorein-DNPH-DNPH is changed to acrorein-DNPH-DNPH-DNPH with an acid atmosphere. As a result of such chemical reaction before extraction, the acrolein-DNPH is detected to low concentration. We found that at the low temperature condition, acrolein-DNPH concentration decrease speed is held down.

Fuel cell vehicles represent a new system, and their safety has not yet been fully proved comparing with present automobile. Thorough safety evaluation is especially needed for the fuel system, which uses hydrogen as fuel, and the electric system, which uses a lot of electricity. The fuel cell stacks that are to be loaded on fuel cell vehicles generate electricity by reacting hydrogen and oxygen through electrolytic polymer membranes which is very thin. The safety of the fuel and electric systems should also be assessed for any abnormality that may be caused by electrolytic polymer membranes for any reasons. The purpose of our tests is to collect basic data to ultimately establish safety standards for fuel cell stacks. Methanol pool flame exposure tests were conducted on stationary use fuel cell stacks of two 200W to evaluate safety in the event of a fire.

This research was conducted to propose appropriate emergency exits for bus crews and passengers. We developed the improved emergency exit based on the results of current bus exit performance tests, and investigated its effect on evacuation readiness. Tests employing human subjects were conducted to measure the time required to evacuate using the improved emergency exit. The subjects' psychological responses during evacuation were also studied to identify any evacuation problems. We also carried out tests of group evacuation through windows in a current bus to obtain the relationship between the evacuation time, the number of evacuation subjects, and the number of windows. The results show that the improved emergency exit is effective in improving evacuation readiness. It is clear that there is a positive correlation between the evacuation time, the number of subjects, and the number of windows.

This paper is an attempt to estimate the traffic demand of private vehicles in the Philippines and Thailand toward 2030. Estimation of road traffic volume is one of the most important elements for determining fuel consumption and emission gas levels. The level of passenger car ownership is still low, but there has been a distinct shift toward passenger cars due to the lack of mass transport. In Asian countries, inspection and maintenance and emission standards are the most important policy measures. The projections of car stock are evaluated as the emissions of PM, CO and NOx by applying these policy measures in the case of Thailand.

In the urea SCR system, urea solution is injected by injector installed in the front stage of the SCR catalyst, and NOx can be purified on the SCR catalyst by using NH3 generated by the chemical reaction of urea. NH3 is produced by thermolysis of urea and hydrolysis of isocyanic acid after evaporation of water in the urea solution. But, biuret and cyanuric acid which may cause deposit are sometimes generated by the chemical reactions without generating NH3. Spray behavior and chemical reaction of urea solution injected into the tail-pipe are complicated. The purpose of this study is to reveal the spray behavior and NH3 generation process in the tail-pipe, and to construct the model capable of predicting those accurately. In this report, the impingement spray behavior is clarified by scattered light method in high temperature flow field. Liquid film adhering to the wall and deposit generated after evaporation of water from the liquid film are photographed by the digital camera.

For the better understanding of nanoparticles observed on the rode side, adding to the emission test on the chassis dynamometer and engine dynamometer test, possible factors for formation of nanoparticles are investigated. As other possible factors, cold starting of transient test cycle, blow-by gas from heavy duty diesel engine without a positive crankcase ventilation, exhaust braking, and plume mixing of vehicle exhausts were investigated. Nuclei mode particles under the transient test cycles formed during fuel cut period, fuel enrichment period and idling period. Concentration of nuclei mode particles during the idling period are depends on exhaust temperature. The higher exhaust temperature courses the lower number concentration but variation range is within twice. Emission rate of nanoparticles from blow-by gas is one thousandth of tail pipe emissions rate and was found to be negligible.

Compared with diesel fuel, FAME is relatively unstable and readily generates acids such as acetic acid and propionic acid. When FAME-blended diesel fuel is used in existing diesel vehicles, it is important to maintain the concentration of FAME-origin acid in the fuel at an appropriately low level to assure vehicle safety. In the present study, the oxidation of diesel fuel containing 5% FAME is investigated. Several kinds of FAMEs were examined, including reagents such as methyl linoleate and methyl linolenate, as well as commercially available products. The level of acid, peroxide, water, and methanol and the pressure of the testing vessel were measured. The result shows that unsaturated FAMEs that have two or more double bonds are unstable. Also, water is generated by oxidation of FAME blended diesel fuel, accelerating corrosion of the terne sheet.

This study addresses the virtual optimization of the technical specifications for a recently developed Advanced Pedestrian Legform Impactor (aPLI). The aPLI incorporates a number of enhancements for improved lower limb injury predictability with respect to its predecessor, the FlexPLI. It also incorporates an attached Simplified Upper Body Part (SUBP) that enables the impactor’s applicability to evaluate pedestrian’s lower limb injury risk also with high-bumper cars. The response surface methodology was applied to optimize both the aPLI’s lower limb and SUBP specifications, while imposing a total mass upper limit of 25 kg that complies with international standards for maximum weight lifting allowed for a single operator in the laboratory setting. All parameters were virtually optimized considering variable interaction, which proved critical to avoid misleading specifications.

In this study, a MPT-HFRR (Multi-Pressure/Temperature High-Frequency Reciprocating Rig) was manufactured based on a diesel fuel lubricity test apparatus. The MPT-HFRR was designed to be used for conventional test methods as well as for liquefied gas fuel tests. Lubricity tests performed on a calibration standard sample under both atmospheric pressure and high pressure produced essentially constant values, so it was determined that this apparatus could be used for assessing the lubricity of fuel. Using this apparatus, the improvement of lubricity due to the addition of a DME (Dimethyl Ether) fuel additive was investigated. It was found that when 50ppm or more of a fatty acid lubricity improver was added, the wear scar diameter converged to 400μm or less, and a value close to the measured result for Diesel fuel was obtained. The lubricity obtained was considered to be generally satisfactory.

To meet the strict emission regulations for diesel engines, an advanced processing device such as a Urea-SCR (selective catalytic reduction) system is used to reduce NOx emissions. The Real Driving Emissions (RDE) test, which is implemented in the European Union, will expand the range of conditions under which the engine has to operate [1], which will lead to the construction of a Urea-SCR system capable of reducing NOx emissions at lower and higher temperature conditions, and at higher space velocity conditions than existing systems. Simulations are useful in improving the performance of the urea-SCR system. However, it is necessary to construct a reliable NOx reduction model to use for system design, which covers the expanded engine operation conditions. In the urea-SCR system, the mechanism of ammonia (NH3) formation from injected aqueous urea solution is not clear. Thus, it is important to clarify this mechanism to improve the NOx reduction model.

The Agency of Natural Resources and Energy, Ministry of Economy, Trade and Industry has conducted conformity tests of diesel fuel containing Fatty Acid Methyl Ester (FAME) to amend diesel fuel standards in Japan. The objective of the tests is to examine appropriate specifications of diesel fuel containing FAME for automotive use for existing vehicles in the Japanese market. The conformity testing includes verification of fuel system component compatibility, tail pipe emissions, and characterization of the reliability and durability of the engine system, including the fuel injection system. In designing the conformity tests, the maximum FAME concentration was 5%. Most of the new standards are essentially equivalent to EN14214, but the total acid number (TAN) of specific acids, and oxidation stability of the new standards for diesel fuel containing FAME, are different from EN14214.

Crosscheck tests of fast electrical mobility spectrometers, Differential Mobility Spectroscopy (DMS) and Engine Exhaust Particle Sizer(EEPS), were conducted to evaluate the accuracy of fine particle measurement. Two kinds of particles were used as test particles for the crosscheck test of instruments: particles emitted from diesel vehicles and diluted in a full dilution tunnel, and particles generated by CAST. In the steady state tests, it was confirmed that the average concentration of each instrument was within the range of ±2σ from the average concentration of all the same type of instruments. In the transient tests, it is verified that the instruments have almost equal sensitivity. For application of the fast electrical mobility spectrometers to evaluation of particle number and size distributions, it is essential to develop a calibration method using reference particle counters and sizers (CPC, SMPS, etc.) and maintenance methods appropriate for each model.

Ferrocene is used as an antiknock additive to replace lead alkyls. To clarify the influence of one metal additive, ferrocene, on engine, following experiments were carried out. The insulation resistance of spark plugs was measured, deposits in the engine were analyzed, and an exhaust emission and fuel economy tests were conducted using gasoline containing ferrocene. The deposit, which contained iron oxides, adhered to the combustion chamber, spark plugs, and exhaust pipe when the engine operated with gasoline containing ferrocene. When vehicles operated with gasoline containing ferrocene, fuel consumption increased and the exhaust temperature rose. In addition, an abnormal electrical discharge pattern was observed in spark plugs operating at high temperatures. Iron-oxide of Fe3O4 is changed into Fe2O3 under high temperatures. Discharge current flows in iron oxides including Fe2O3 because the conductivity of Fe2O3 increases at high temperatures.

To achieve a method for flame exposure testing of high-pressure cylinders in automobiles that allows fair evaluations to be made at each testing institute and also provides high testing accuracy, we investigated the effects of the flame scale of the fire source, the fuel type, the shape of the pressure relief device shield, and the ambient temperature through experiments and numerical simulation. We found that, while all of these are factors that influence evaluation results, the effects of some factors can be reduced by increasing the flame size. Therefore, a measurement technique to quantitatively determine the flame size during the test is required. Measuring temperatures at the top of each cylinder is a candidate technique. Furthermore, flame exposure tests to be conducted on cylinders as single units must ensure safety during a vehicle fire.

Our study was conducted to demonstrate the primary factors involved in fires which result from an automobile's electrical wire harness system with fuses. In our experiments we used modeled automobile wire harnesses to study the processes of ignition and the resultant fires. Current was passed through blade type fuses to a portion of the harness and was intermittently short-circuited by a grounded metal plate. The nominal current ratings of the fuses we used were lower than or equal to 30 amperes [A], and the operating current was 30A at 12 Volts. Current flowed to the harness specimens through a DC power source. We found that electrical tracking with scintillation, caused by a weak electric flow through carbonized wire insulation, rarely generated flames in the wire harnesses without blowing the fuse. Ignition was never observed on the insulation near the areas shorted by the arc and/or overloaded currents going to the wire elements.

In applying the ISO 26262 controllability classification for motorcycles in actual riding tests, a subjective evaluation by expert riders is considered to be the appropriate approach from the viewpoint of safety. We studied the construction of an expert-rider-based C class evaluation method for motorcycles and developed some evaluation test cases reproducing various hazardous events. We determined that it was necessary to accumulate more evaluation cases for further representative scenarios and that, to avoid variations in such evaluations, a method in which different expert riders can carry out testing following a common understanding had to be devised. Considering these problems for practical application, this study aimed at establishing an actual riding test method for C class evaluation by expert riders and to develop a deeper understanding of test procedures and management.

Four urea SCR systems were developed and evaluated on a C/D and on the road to investigate their potential for Japanese emission regulations in 2005 and beyond. Test results showed that NOx conversion ratios were 50 to 70% during the Japanese D13 mode cycle, and the ratios under the transient driving cycle were lower than those tested during a steady state. Unregulated emissions, such as benzene, aldehyde and benzo[a]pyrene, existed either at a trace level using the oxidation catalyst, or lower than a base diesel engine, when no oxidation catalyst was used. The health effects of particulate matter emitted from the SCR system were almost the same as those from conventional diesel engines, as evaluated by the Ames test and in vitro micronucleus test. Thermal degradation products, such as cyanuric acid and melamine, were two to four figures lower compared with the toxicological information of Safety Information Resources Inc. (SIRI).

ISO 26262, an international functional safety standard of electrical and/or electronic systems (E/E systems) for motor vehicles, was published in November 2011 and it is expected that the scope will be extended to motorcycles in a second edition of ISO 26262 going to be published in 2018. In order to apply ISO 26262 to motorcycle, proper estimation of Exposure, Controllability, and Severity are key factors to determine Motorcycle Safety Integrity Level (MSIL). Exposure is a factor to indicate the probability of the state of an operational situation that can be hazardous with the E/E system malfunction. And it is not easy to estimate the motorcycle Exposure due to less availability of back ground data in actual operational situation compared to motor vehicle. Therefore real traffic situation should be investigated in order to provide rationales for MSIL determination.

The SAE Fuel Cell Vehicle (FCV) Safety Working Group has been addressing FCV safety for over 11 years. In the past couple of years, significant attention has been directed toward a revision to the standard for vehicular hydrogen systems, SAE J2579(1). In addition to streamlining test methodologies for verification of Compressed Hydrogen Storage Systems (CHSSs) as discussed last year,(2) the working group has been considering the effect of vehicle fires, with the major focus on a small or localized fire that could damage the container in the CHSS and allow a burst before the Pressure Relief Device (PRD) can activate and safely vent the compressed hydrogen stored from the container.