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In 1999, the first generation NOx sensor from NGK Spark Plug, Co., Ltd. was commercialized for use in gasoline LNT NOx after-treatment systems [ 1 ]. Since then, as emissions regulations and OBD requirements have become more stringent, the demand for a high-accuracy NOx sensor with fast light-off has increased, particularly for diesel after-treatment systems. To meet such market demands, NGK Spark Plug, Co., Ltd. has developed, in collaboration with Ford Motor Company, a second generation NOx sensor.

Seated vertical vibration thresholds were tested using an adaptive Levitt algorithm. All such testing raises issues concerning potential shifting of thresholds during testing as subjects improve at the task. Additional testing was done at 4 and 16 Hz to quantify the adequacy of training within the algorithm. A 3-down 1-up algorithm starting at 8 mG descended in 3 dB steps until the first error, then switched to 1 dB steps and continued for 9 more reversals, with the last 6 averaged for threshold. Stimuli were paired with intervals containing no vibration in random order. Subjects closed their eyes and were presented with sounds in earphones to indicate the stimulus intervals, and chose the interval they thought contained the stimulus. A combination of eyes closed for concentration, gradual approach to the threshold, 4 reversals before data was used, and feedback on each trial provided built-in training to avoid threshold shift.

A traction test machine, developed for evaluation of traction-CVT fluids for the automotive consortium, USCAR, provides precision traction measurements to stresses up to 4 GPa. The high stress machine, WAMhs, provides an elliptical contact between AISI 52100 steel roller and disc specimens. Machine stiffness and positioning technology offer precision control of linear slip, sideslip and spin. A USCAR traction test methodology includes entrainment velocities from 2 to 10 m/sec and temperatures from -20°C to 140°C. The purpose of the USCAR machine and test methodology is to encourage traction fluid development and to establish a common testing approach for fluid qualification. The machine utilizes custom software, which provides flexibility to conduct comprehensive traction fluid evaluations.

Ford Motor Company is participating in the Department of Energy's (DOE) Ultra-Clean Transportation Fuels Program with the goal to explore the development of innovative emission control systems for advanced compression-ignition direct-injection (CIDI) transportation engines. CIDI (or diesel) engines have the advantages of a potential 40% fuel economy improvement and 20% less CO2 emissions than current gasoline counterparts. To support this goal, Ford plans to demonstrate an exhaust emission control system that provides high efficiency particulate matter (PM) and NOx reduction. Very low sulfur diesel fuel will be used to enable low PM emissions, reduce the fuel economy penalty associated with the emission control system, and increase the long-term durability of the system. The end result will allow vehicles with CIDI engines to be Tier II emissions certified at a minimum cost to the consumer.

In this paper, the formability of AA5754 aluminum laser-welded blanks produced by Nd:YAG laser welding is investigated under biaxial straining conditions. The mechanical behavior of the laser-welded blanks is first examined by uniaxial tensile tests conducted with the weld line perpendicular to the tensile axis. Shear failure in the weld metal is observed in the experiments. Finite element simulations under generalized plane strain conditions are then conducted in order to further understand the effects of weld geometry and strength on the shear failure and formability of these welded blanks. The strain histories of the material elements in the weld metal obtained from finite element computations are finally used in a theoretical failure analysis based on the material imperfection approach to predict the failure strains for the laser-welded blanks under biaxial straining conditions.

Environmental concerns have prompted increasingly stringent government legislation regulating automotive fuel economy and emissions. Recent rules not only mandate lower total emissions, but also require on-board diagnostics which monitor the vehicle exhaust systems. In order to satisfy these requirements, new and improved exhaust gas sensors are continually being developed to serve as part of the engine feedback control and emissions monitoring systems. Before we can properly design these new sensors, we must attempt to better understand the harsh environment in which they will operate. In this paper, we examine the high frequency nature of pressure fluctuations found in the exhaust system for both steady state and transient engine operating conditions. We also investigate temperature fluctuations, but restrict these measurements to the sampling environment found in the packaging of a Ford Si-based microcalorimeter.

A planar dielectric barrier discharge device has been tested for exhaust emission reduction in simulated engine exhaust. This device's electrical characteristics have been measured and are presented in this paper. The device consists of two dielectric barriers which act like series capacitors, with the gas gap between them. At low gap voltages, the gas gap also acts like a capacitance, with a much smaller capacitance than the barriers. At higher voltages, the gas gap breaks down and a blue–purple glow visually fills the gap. The partially ionized gas conducts charge across the gap, building electrical charge on the dielectric barrier inner surface. When the AC excitation voltage peaks and starts to go toward an opposite polarity, the discharge momentarily extinguishes, trapping charge in the dielectric barrier capacitance.

The direct injection gasoline spray-wall interaction was characterized inside a heated pressurized chamber using various visualization techniques, including high-speed laser-sheet macroscopic and microscopic movies up to 25,000 frames per second, shadowgraph, and doublespark particle image velocimetry. Two hollow cone high-pressure swirl injectors having different cone angles were used to inject gasoline onto a heated plate at two different impingement angles. Based on the visualization results, the overall transient spray impingement structure, fuel film formation, and preliminary droplet size and velocity were analyzed. The results show that upward spray vortex inside the spray is more obvious at elevated temperature condition, particularly for the wide-cone-angle injector, due to the vaporization of small droplets and decreased air density. Film build-up on the surface is clearly observed at both ambient and elevated temperature, especially for narrow cone spray.