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This paper presents a laboratory study of body dimensions, seated posture, and seatbelt fit for children weighing from 40 to 100 lb (18 to 45 kg). Sixty-two boys and girls were measured in three vehicle seats with and without each of three belt-positioning boosters. In addition to standard anthropometric measurements, three-dimensional body landmark locations were recorded with a coordinate digitizer in sitter-selected and standardized postures. This new database quantifies the vehicle-seated postures of children and provides quantitative evidence of the effects of belt-positioning boosters on belt fit. The data will provide guidance for child restraint design, crash dummy development, and crash dummy positioning procedures.

Several diesel passenger car manufacturers in the European Union recently announced the future use of catalyzed diesel particulate filter systems on their vehicles. The major technical challenge is the periodical regeneration of the filters loaded with the retained diesel particulates. In order to promote filter regeneration, catalytic activation of the accumulated soot is advantageous. Therefore, the first serial application of diesel particulate filter systems uses catalytically active fuel additives. These systems were introduced about four years ago. Since that time, other systems, using a dedicated catalytically activated diesel particulate filter combined with an upstream diesel oxidation catalyst, have been introduced as well. This allows filter regeneration without extra fuel additives. In the past, adding catalytic coating to a filter substrate has often resulted in increasing the pressure drop over the filter to an unacceptable level.

This paper reports on the desired performances for Catalyzed Soot Filters (Hereinafter referred as “CSF”), which is composed of a Diesel Particulate Filter (DPF) coated with an Oxidation Catalyst, its design factors and their influence on DPF performance, and on the lifetime prediction method to effectively design a DPF for durability. Performance means pressure drop, Particulate Matter (PM) regeneration limit, time for light-off, and canning strength. Design factors include cell structure, overall DPF size and material porosity. Knowing the relationships between performance and design factors assist the engineer in optimizing the selection of material, cell structure and size of the DPF.

It has been reported that particulate emissions from diesel vehicles could be associated with damaging human health, global warming and a reduction in air quality. These particles cover a very large size range, typically 3 to 10 000 nm. Filters in the vehicle exhaust systems can substantially reduce particulate emissions but until very recently it was not possible to directly characterise actual on-road emissions from a vehicle. This paper presents the first study of the effect of filter systems on the particulate emissions of a heavy-duty diesel vehicle during real-world driving. The presence of sulfur in the fuel and in the engine lubricant can lead to significant emissions of sulfate particles < 30 nm in size (nanoparticles).

DPF design, system integration, regeneration control strategy optimization and ash ageing assessment, based on a traditional design of experiments approach becomes very time consuming and costly, due to the high number of tests required. This provides a privileged window of opportunity for the application of simulation tools and hence simulation is increasingly being used for the design of exhaust after-treatment systems with a Diesel Particulate Filter (DPF). DPF behavior depends strongly on the coupling of physico-chemical phenomena occurring over widely disparate spatial and temporal scales and a state-of-the-art simulation approach recognizes and exploits these facts introducing certain assumptions and/or simplifications to derive an accurate but computationally tractable DPF simulation tool, for the needs of industrial users.

The IVT control system can be viewed as having two distinct roles, namely that of steady state and transient torque management. Steady state management functions consist of setting engine power and transmission reaction torque to achieve optimal fuel economy, emissions and driver demanded wheel torque. The transient torque management function defines additional engine and transmission reaction torques, based on known inertia and plant responses, to manage the transition between these steady state operating points according to the driver's wishes, subject to plant constraints. This paper gives a basic overview of the IVT steady state control functions, leading onto a detailed description of the transient torque management function. The software functions are illustrated in block diagram format, using simulation verification data plots and vehicle data logs for validation purposes.

This paper is a report of the findings and insights derived from a continuously variable transmission (CVT) research study. The research objective was to identify relationships between key CVT parameters and the customer perception of CVT performance. Four factors were studied: Ratio Schedule, Shift Speed, Dead Pedal, and Torque Converter Lock. Researchers evaluated the influence of these factors and their interactions on customer perception. Although one calibration is not significantly better than others, customers preferred three out of sixteen calibrations. DOE analysis shows flat ratio schedule to be statistically significant for Power and Pick-up. Several 2-way interactions are also statistically significant. Although a trade-off study must be completed to identify the best setting for a given vehicle, two calibration methods may be employed for higher customer satisfaction:

In order to reduce tail-pipe hydrocarbon emissions from SI gasoline engines, rapid catalyst warm-up and improvement of catalyst conversion efficiency are important. There are many reports which have been published by manufacturers and research institutes on this issue. For further reduction of tail-pipe hydrocarbon emissions, it is necessary to reduce engine-out hydrocarbon emissions and to improve after treatment, during the time the catalyst is not activated. This paper quantitatively analyzed the fuel amount of intake port and cylinder wall-wetting, burned fuel and engine-out hydrocarbon emissions, cycle by cycle in firing condition, utilizing a specially designed analytical engine. The effect of mixture preparation and fuel properties for engine-out hydrocarbon emissions, during the cold engine start and warm-up period, were quantitatively clarified.

Six forces act on the block of a metal pushing V-belt. Previously, we successfully measured these forces at steady states using devised blocks and a telemeter system. In this paper, six forces are measured using the same testing and measuring systems at transitional states where a speed ratio varies from low to high, or vice versa. The experimental results reveal that distributions of four forces at transitional states except normal and frictional forces between rings and blocks are different in shape from those at steady states.

This paper describes results from a survey of older children with respect to vehicle and booster restraints. The work first consisted of a rudimentary anthropometry study of 155 volunteers aged between 7 and 12 years. The data were compared to an extensive child anthropometry study conducted by the University of Michigan in 1975. Height and sitting height data matched well, while children in the current study appeared heavier. In the restraint fit survey, each child sat in the rear seat alone and in three belt-positioning booster seats (Volvo, Kangaroo, Century CR-3) in three vehicles (Ford Taurus, Pontiac Sunbird, Dodge Caravan). Booster seats greatly improved belt fit over the rear seat alone. The majority of children in this study had better belt fit with the boosters than with the rear seat alone, regardless of size. However, children who could fit well in the boosters and had good or fair belt fits were generally 36 kg or less.

The liquid fuel entry into the cylinder and its subsequent behavior through the combustion cycle were observed by a high speed CCD camera in a transparent engine. The videos were taken with the engine firing under cold conditions in a simulated start-up process, at 1,000 RPM and intake manifold pressure of 0.5 bar. The variables examined were the injector geometry, injector type (normal and air-assisted), injection timing (open- and closed-valve injection), and injected air-to-fuel ratios. The visualization results show several important and unexpected features of the in-cylinder fuel behavior: 1) strip-atomization of the fuel film by the intake flow; 2) squeezing of fuel film between the intake valve and valve seat at valve closing to form large droplets; 3)deposition of liquid fuel as films distributed on the intake valve and head region. Some of the liquid fuel survives combustion into the next cycle.

Block compression force and ring tension of a metal pushing V-belt type CVT have been experimentally measured at steady states. The peculiar transmitting mechanisms for this type of belts has also been outlined based on the experimental results in the previous works. In this paper, other forces simultaneously acting on a block at steady states were measured using newly developed devised blocks. These forces are frictional force between blocks and rings, normal force between blocks and pulleys, frictional forces between blocks and pulleys in radial and tangential directions. The transmitting mechanisms for the metal pushing V-belt type CVT were drawn in detail based on new experimental data. The following conclusions are emphasized in the present work. (1) A cohesive point where the block coheres with the ring exists in the pulley having a larger pitch radius at all conditions. This is not dependent on speed ratio and transmitting torque.

Speciated HC emissions from the exhaust system of a production engine without an active catalyst have been obtained with 3 sec time resolution during a 70°F cold start using two control strategies. For the conventional cold start, the emissions were initially enriched in light fuel alkanes and depleted in heavy aromatic species. The light alkanes fell rapidly while the lower vapor pressure aromatics increased over a period of 50 sec. These results indicate early retention of low vapor pressure fuel components in the intake manifold and exhaust system. Loss of higher molecular weight HC species does occur in the exhaust system as shown by experiments in which the exhaust system was preheated to 100° C. The atmospheric reactivity of the exhaust HC emissions for photochemical smog formation increases as the engine warms.

Ongoing developments in crash safety research, regulations and product enhancements have indicated the need for a review on child dummy design philosophies. Late 1991, the TNO Crash-Safety Research Centre started a research program including a review on child anthropometry, a literature study on biomechanical properties of children and a study on scaling techniques. The objective of this research program is to establish sets of requirements for basic child dummy “design characteristics”. The main design characteristics covered in this paper are anthropometry and biofidelity. The anthropometry study resulted in a new TNO database on child anthropometry and includes published data on more than 75 parameters. The database's background and construction are explained and the main parameters for child dummy design are presented. The literature study on biomechanical properties of children revealed a limited set of data on material properties.

This paper details the development of the EX-80 composition, a new cordierite material for use as a diesel particulate filter (DPF), that was developed based on the following objectives; (1) improved thermal durability, (2) high filtration efficiency and (3) low pressure drop. The achievement of these goals was demonstrated through engine testing, stress modeling, and other evaluations. EX-80 has a low coefficient of thermal expansion (CTE) averaging less than 4x10-7°C-1 (25°C-800°C), the Modulus of Rupture (MOR) averages greater than 350 psi and the Modulus of Elasticity (MOE) averages less than 0.8 x 106 psi. The improvement of these three properties has resulted in improved thermal durability for EX-80 as compared to the current Corning DPF compositions (EX-47, EX-54 and EX-66). The new cordierite composition has been designed to achieve a low pressure drop as a function of soot loading (0.30 inHg/gm of soot collected), coupled with high efficiency, averaging greater than 90%.

The requirement of reducing HC emissions during cold start and improving transient performance has prompted a study of the fuel injection process. Port-fuel-injection with the Intake-valve open using small droplets is a potentially feasible option to achieve the goals. To gain a better understanding of the injection process, the effects of droplet size, injection timing, and coolant temperature on the total and speciated HC emissions were tested In a Single-cylinder engine. It was found that droplet size plays an important role in the total HC emission increase during open-valve injection, especially with cold operation. Large droplets (300 μm SMD) produced a substantial HC increase while small droplets (14 μm SMD) produced no observable increase. Increase In the total HC emissions was always accompanied by an increase in the heavy fuel components in the exhaust gases.

Since 1987, Van Doorne's Transmissie (VDT) BV has produced a steel belt for continuously variable transmission (CVT) applications. To date, over 750,000 vehicles have been equipped with the system, and belt reliability has proved to be very high. During the early stages of transmission production, an intermittent lubricant-related noise problem was encountered. This paper describes the steps taken to isolate the noise source and eliminate it. The noise, commonly called the “scratch phenomenon,” manifests itself as a transfer-gear rattle under slow-speed, light-load conditions. Initial investigation revealed that the scratch phenomenon could be avoided by using an alternative transmission fluid (1). Experimental work conducted by Lubrizol and VDT to understand the mechanism behind the problem: Established a relationship between the occurrence of the scratch phenomenon and the stick-slip properties of the belt-material/lubricant combination.

In this study, distributions of block compression force on the driving and driven pulleys were measured using a tiny load-cell inserted between two blocks and a telemeter system, under several constant speed ratios. Ring tension distributions were also measured using a specially devised block. From the experimental results, the following conclusions were drawn: (1) Block compression force distribution on the driving pulley is significantly different from that on the driven pulley. (2) Ring tension takes different value at each side of strings. It is considered that this phenomenon is caused by difference of saddle surface speed between two pulleys.

The trend towards increased individualism concerning the car's response to drivers' preferences is evident. In combination with the desire for high performance plus severe legal requirements on fuel consumption and emission levels this sets the powertrain engineer an almost impossible task. A Continuously Variable Transmission with full electronic control offers an opportunity to meet this challenge due to its infinite number of ratios within a wide ratio span. Based on the experience with 600000 CVT-cars in the field equipped with the VDT-belt a 250 Nm-CVT has been developed. This up-range CVT model features electronic controls for ratio and line pressure control, a torque convertor with lock-up and flow controlled pump. The transmission has been fitted to a 3, 3 I Chrysler Voyager.