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To investigate the events that could arise when fighting fires in vehicles with carbon fiber reinforced plastic (CFRP) hydrogen storage cylinders, we conducted experiments to examine whether a hydrogen jet diffusion flame caused by activation of the pressure relief device (PRD) can be extinguished and how spraying water influences the cylinder and PRD. The experiments clarified that the hydrogen jet flame cannot be extinguished easily with water or dry powder extinguishers and that spraying water during activation of the PRD may result in closure of the PRD, but is useful for maintaining the strength of CFRP composite cylinders for vehicles.

We have developed a new propane burner that satisfies the requirements of localized fire test which was presented in SAE technical paper 2011-01-0251. This paper introduces the specifications of this burner and reports its characteristics as determined from various fire exposure tests that we conducted in order to gather data. These tests included temperature and heat flux distribution on cylinder surfaces, which would be useful for the design of automotive compressed fuel cylinders. Our fire exposure tests included localized and engulfing fire tests to compare TPRD activation time, cylinder burst pressure and other parameters between different flame configurations and tests to identify the effects of an automotive compressed fuel cylinder on localized fire test results.

In Biodiesel Fuel Research Working Group(WG) of Japan Auto-Oil Program(JATOP), some impacts of high biodiesel blends have been investigated from the viewpoints of fuel properties, stability, emissions, exhaust aftertreatment systems, cold driveability, mixing in engine oils, durability/reliability and so on. This report is designed to determine how high biodiesel blends affect oil quality through testing on 2005 regulations engines with DPFs. When blends of 10-20% rapeseed methyl ester (RME) with diesel fuel are employed with 10W-30 engine oil, the oil change interval is reduced to about a half due to a drop in oil pressure. The oil pressure drop occurs because of the reduced kinematic viscosity of engine oil, which resulting from dilution of poorly evaporated RME with engine oil and its accumulation, however, leading to increased wear of piston top rings and cylinder liners.

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.

In this study, we evaluated the fire safety of vehicles that use compressed hydrogen as fuel. We conducted fire tests on vehicles that used compressed hydrogen and on vehicles that used compressed natural gas and gasoline and compared temperatures around the vehicle and cylinder, internal pressure of the cylinder, irradiant heat around the vehicle, sound pressure levels when the pressure relief device (PRD) was activated, and damage to the vehicle and surrounding flammable objects. The results revealed that vehicles equipped with compressed hydrogen gas cylinders are not more dangerous than CNC or gasoline vehicles, even in the event of a vehicle fire.

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.

Instantaneous temperature of in-cylinder gas provides a lot of useful and local information for analyzing the combustion process in an internal combustion engine. From the standpoint of applicability to a practical engine, the infrared monochromatic radiation pyrometry required only a single optical window is considered to be more suitable comparing with the conventional infrared absorption-emission pyrometry with two optical windows. Then, the former pyrometer is used to measure the mean gas temperatures averaged on an optical path (or cylinder diameter) of a spark ignition engine connected to a prechamber with a torch nozzle of various area sizes. These measured temperature-crankangle diagrams not only clarify the influences of torch jet flow on the combustion processes, but also correspond well to the heat release rates calculated from the pressure diagrams.

The Advanced Clean Energy Vehicle Project (ACE Project) has been initiated to develop the vehicles which can utilize oil-alternative and clean fuels and achieve twice the energy efficiency of conventional vehicles. To achieve the project objectives, Japanese automobile manufactures are developing six types of hybrid vehicles. Technologies of the developing vehicles include many kinds of hybrid elements, such as series and series/parallel types, alternative fuels (natural gas, DME, methanol) internal combustion engines and a fuel cell, as well as flywheels, ultra-capacitors and Li-ion batteries. This paper introduces the outline of ACE project.

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.