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Child restraint head padding is designed for the child's comfort under normal use. Under vehicle crash conditions, however, the padding in a rear facing child restraint may not be designed to sufficiently absorb impact energy. The objective of this paper is to evaluate the effects of various head padding conditions in rear facing child restraints in frontal impacts. Five sled tests were performed to measure the response of a CRABI 12 month dummy to different padding conditions in a rear facing child restraint. Static loading tests were performed on the padding materials. Results show that using padding of low stiffness increases head acceleration and HIC15 values.

With the development of the addition-type polyimide resins, a need arose for a coupling agent that would improve the performance of the fiber-resin interface under thermal stress. Research work was carried out to develop such a material and resulted in a new coupling agent for use at high temperatures. The test data generated from glass fiber reinforced composites using this new coupling agent, and the study of the interface using the scanning electron microscope, demonstrate an improvement in the cohesive and interfacial shear of the glass fiber-resin matrix. This development has provided the designer with a material that retains its structural integrity under extreme thermal conditions.

The following paper describes the operational experience of using blended or heavy fuels for inland marine service. The experience outlined here is with a vessel retrofitted to specifically use 2000 Redwood No. 1, seconds, fuel and designed to increase blended fuel-oil viscosity rising as high as 3500 Redwood. An engine teardown was performed and no abnormal wear was noticed.

To aid in better assessing the corrosion performance of AZ91 die cast magnesium, standard salt spray corrosion tests have been made on both randomly selected commercial die castings and on three series of controlled purity test panels. The results reveal that the poor performance often associated with magnesium parts in salt spray are due principally to iron, nickel, and copper contamination levels. When these contaminants were limited, severe pitting corrosion was eliminated and the salt spray performance was good to excellent when compared to 380 aluminum and cold rolled steel.

The emission of nanoparticles from combustion engines has been shown to have a poorly understood impact on the atmospheric environment and human health, and legislation tends to err on the side of caution. Researchers have shown that Gasoline Direct Injection (GDI) engines tend to emit large amounts of small-sized particles compared to diesel engines fitted with Diesel Particulate Filters (DPFs). As a result, the particulate number emission level of GDI engines means that they could face some challenges in meeting the likely EU6 emissions requirement. This paper presents size-resolved particle number emissions measurements from a spray-guided GDI engine and evaluates the performance of an Evaporation Tube (ET). The performance of an Evaporation Tube and hot air dilution system with a 7:1 dilution ratio has been studied, as the EU legislation uses these to exclude volatile particles.

Hydrogen assisted jet ignition (HAJI) is a pre-chamber ignition system for standard gasoline fueled engines that involves the use of a chemically active turbulent jet to initiate combustion in lean fuel mixtures. HAJI burns the lean main charge rapidly and with almost no combustion variability, which allows for low hydrocarbon emissions and almost zero NOx, due to lower peak temperatures. This paper focuses on the effects of internal and cooled external exhaust gas recirculation (EGR) on combustion parameters, emissions and thermal efficiency in a single cylinder HAJI equipped CFR engine. Experimental results indicate that replacing air with EGR in λ=2 mixtures can shift the lean limit at which NOx is negligible to mixtures as rich as λ=1.3, without a large penalty in hydrocarbon emissions and thermal efficiency.

The effect of hydroforming on the mechanical properties and dynamic crush behaviors of tapered aluminum 6063-T4 tubes with octagonal cross section are investigated by experiments. First, the thickness profile of the hydroformed tube is measured by non-destructive examination technique using ultrasonic thickness gauge. The effect of hydroforming on the mechanical properties of the tube is investigated by quasi-static tensile tests of specimens prepared from different regions of the tube based on the thickness profile. The effect of hydroforming on the dynamic crush behaviors of the tube is investigated by axial crush tests under dynamic loads. Specimens and tubes are tested in two different heat treatment conditions: hydroformed-T4 (as-received) and T6. The results of the quasi-static tensile tests for the specimens in hydroformed-T4 condition show different amounts of work hardening depending on the regions, which the specimens are prepared from.

An experimental investigation was carried out to assess the effect on engine operation of the addition of 20% hydrogen by volume to natural gas. Blends of hydrogen and natural gas are referred to as hythane in this report. Three groups of testing were conducted. All the tests were conducted at light loads similar to those in urban driving. The first group of tests were conducted using a 2.0 liter Nissan four cylinder engine to measure the increase in flame front propagation rate when fueled with hythane as compared to pure methane (simulating natural gas). The second group of tests were conducted with a 1.6 liter Toyota four cylinder engine to measure the changes in emissions and thermal efficiency comparing hythane operation to pure methane operation.

High hydrogen containing atmospheres, such as endothermic gas and dissociated ammonia, effectively remove much of the sulfur that is added to ferrous compacts for machinability. Sulfur loss was found to decrease with lower hydrogen concentrations in the atmosphere. The high hydrogen sulfide concentrations present with high hydrogen atmospheres will reduce the life expectancy of the metal components in the furnace. Low hydrogen concentrations in the atmosphere produce little hydrogen sulfide and expected belt and muffle life will significantly increase. Additions of water to the sintering atmosphere did not appear to have a significant effect on the sulfur content of the compacts.

In order to realize the high compression ratio and high dilution combustion toward improvement in thermal efficiency, the improvement in stability of ignition and initial phase of combustion under the high gas flow field is the major challenge. In terms of the shift on the higher power side of the operating point by downsizing and improvement of real world fuel consumption, the improvement of ignitability is increasingly expected in the wide operating range also including high load and high engine speed region. In this study, the effects of the gas pressure, gas flow velocity near the spark gap at ignition timing, and discharge current characteristics on spark channel formation were analyzed, focusing on restrike event and spark channel stretching in the spark channel formation process. And the relationship between the average discharge current until 1 ms and the EGR combustion limit was considered.

The effects of ignition location on combustion duration, thermal efficiency, exhaust emissions, cyclic variability, and knock sensitivity were investigated in two premixed-charge spark-ignition engines with disk-shaped combstion chambers and having high levels of swirlu. Except for very lean high-swirl conditions, peripheral ignition produced a longer combustion duration than did central ignition, but the difference was less than expected from geometric considerations alone. Flame holding at the spark electrodes, observed in high-speed schlieren films, enhances mass-burning rates for off-center ignition locations. For a swirl number of 4 no significant differences with ignition location were measured in thermal efficiency, heat-transfer losses, exhaust temperature, cyclic variability, or exhaust emissions, but with peripheral ignition the engine had a greater knock sensitivity, lower knock-1imited peak power, and a misfire problem of unidentified origin.

This report presents results from a performance evaluation study on the adequacy of the image size, within school bus cross view mirrors, mandated by FMVSS 111 The mandated image size is 9X3 minutes of arc (ie, 9′X3′) Six observers discriminated the orientation offset of three different image sizes (ie, 45′X15′, 9′X3′, 13.5′X45′) presented onto a banana type cross view mirror. The images were presented to observers under three luminance contrast levels 15%, 20%, and 25%. Results indicated that poor performance was associated with the 45′X15′ image size at all contrast levels and the 9′X3′ image size at a luminance contrast of 15%. The 135′X45′ image size was associated with good performance. In conclusion, measures of performance failed to demonstrate an unequivocal deficiency of the 9′X3′ image size.

The goal of this research was to find the effects of the most important design parameters on passenger cars during “Untripped On-Road Rollover” maneuvers. This work involved studies of vehicle behavior under severe maneuvering conditions include rollover, which was done by using a computer simulation. In order to get a good insight into the effects of design parameters and sensitivity of vehicle rollover to each parameter, a 16 degree of freedom vehicle dynamic model with Pacejka tire model and necessary submodels were developed. Validation was done using standard test results for a passenger car. In order to simulate severe maneuvers, some of suggested test procedures of related organizations were studied. Finally, the J-Turn and Obstacle Avoidance tests were selected. According to the results of this study, some design comments for better vehicle on-road rollover stability were specified.

The electrochemical and corrosion behavior of metals in aqueous environments has received substantial attention. However, relatively little work has been devoted to the electrochemistry and corrosion of metals in non-aqueous environments. Now, with greater pressures to increase fuel efficiencies and decrease exhaust emissions, alternatives and additives to gasoline (including methanol and ethanol) are receiving increased attention from government agencies and automobile manufacturers. Unfortunately, fundamental studies of the corrosion behavior of metals in these solutions are scarce. The objective of the present work is to investigate the electrochemical and corrosion behavior of iron in methanolic solutions containing Cl, H+, SO42-, and H2O. To accomplish this, a full factorial design test matrix was developed to systematically evaluate the effects of these impurities on the corrosion behavior of iron.

Direct injection spark-ignition (DISI) engines have been shown to have much higher engine-out hydrocarbon emissions (HC) than port fuel injected (PFI) engines. A major contribution to the increase in HC emissions is from the in-cylinder surface wetting that occurs as the fuel is injected. A previous study using an optical access engine and a fuel concentration probe demonstrated that the in-cylinder flow field and injection timing have a significant effect on the equivalence ratio at the spark plug. This study continues that work, by using a fast spectroscopic HC emission measurement device (Fast-Spec) to study time-resolved HC emissions from a 4-valve, centrally injected, single cylinder DISI engine. Three flow fields are studied: tumble, reverse tumble and stock. The tumble and reverse tumble flow fields are achieved using shrouded valves. Both early and late start of injection (SOI) timings are investigated.

Chest injuries occur frequently in frontal collisions. During impact, tension in the lap belt is transferred to the inboard shoulder belt, which compresses the lower ribs of the occupant. In this research, inboard shoulder belt and lap belt geometries and forces were investigated to reduce chest deflection. First, the inboard shoulder belt geometry was changed by the lap/shoulder belt (L/S) junction for the rear seat occupant in sled tests using Hybrid III finite element simulation, sled tests and THOR simulation. As the L/S junction was closer to the ASIS (anterior superior iliac spine), chest deflection of the Hybrid III was smaller. The L/S junction around the ilium has the potential to reduce chest deflection without significant increase of head excursion. For THOR, although the chest deflection reduction effect due to closer L/S junction to the ASIS was observed, chest deflection was still substantially large since the lap belt overrode the ASIS.

The initial flame kernel behavior in a SI engine was measured by a spark-plug-fiber-optics probe. From these measurements, the flame kernel may be characterized by an expansion speed and a convection velocity. These quantities were correlated with the bum rate on a cycle-to-cycle basis in an engine configurated with quiescent, swirl, and tumble in-cylinder motion. The expansion speed correlates well with the 0-2 percent mass burn duration for all the configurations. The flame convection velocity depends on the in-cylinder motion in the expected manner. There was, however, only a weak correlation between the 10-90 percent burn duration and the initial flame kernel behavior.

The present study aims to obtain a strategy for optimizing the combination of injection conditions and combustion chamber geometry to achieve low carbon monoxide (CO), nitrogen oxides (NOx) and smoke emissions with high thermal efficiency at low loads in direct-injection premixed charge compression ignition (DI-PCCI) operation in a diesel engine. To this end, experiments were performed using a naturally-aspirated single-cylinder DI diesel engine equipped with a common-rail injection system and a cooled exhaust gas recirculation (EGR) system under various injection conditions, including injection timing, injection angle and injection quantity, and combustion chamber geometry. The results indicate that CO emission was reduced at injection timings that provide high peak heat release rates. To improve the NOx-CO trade-off relation, the spray angle should be properly selected depending on the combustion chamber geometry.

In this study, a series of tests have been carried out to evaluate the effects of the injection rate and timing on bsfc, NOx, and PM emissions in a heavy-duty diesel engine with TICS FIE system. Injection line pressure, cylinder pressure, NOx and smoke were measured with various injection times and injection rates. The injection rate was altered at a fixed injection timing, which could be realized either by changing the TICS setting time or by using different cam profiles. The injection time was varied by using TICS timing control function at a given setting time. A parametric study of the injection rate in in-line pump system was tried to correlate injection rate variations with combustion characteristics and emission. Two parameters, the injection pressure rising rate and the initially injected fuel quantity were introduced to characterize fuel injection.

European standards have set stringent PN (particle number) regulation (6×1011 #/km) for gasoline direct injection (GDI) engine, posing a great challenge for the particulate emission control of GDI engines. Dual-injection, which combines direct-injection (DI) with port-fuel-injection (PFI), is an effective approach to reduce particle emissions of GDI engine while maintaining good efficiency and power output. In order to investigate the PN emission characteristics under different dual-injection strategies, a DMS500 fast particle spectrometer was employed to characterize the effects of injection strategies on particulates emissions from a dual-injection gasoline engine. In this study, the injection strategies include injection timing, injection ratio and injection pressure of direct-injection.