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This paper discusses the French ESV program. The relationship between the ESV program and the overall highway safety effort is explained. Plans to achieve these objectives are outlined. Problems arising from administrative decisions are analyzed.

After 300 kph the aerodynamics noise emitted by the French High Speed Train T.G.V. (Train Grande Vitesse) becomes preponderant. The pantograph and roof environment located in the top of the rear power car are one of the sources which participate in the overall noise of the train. Investigations in an anechoi'c wind tunnel are performed firstly with a real pantograph, secondly with a fine 117 scale power car model. After a trainborne Velocimetry Laser Doppler campaign, the real turbulent boundary layer is simulated in the wind tunnel. The decreasing of the radiated noise level is obtained by modifying the geometry of both the pantograph and the roof and by adding devices on the pantograph itself. These results suggest that close attention needs to be paid to the roof geometry.

The European Space Agency is presently funding the development of a new facility which could be used for the thermal control of : automated space platforms such as EURECA the modules of the future space station other manned space vehicule such as HERMES. The reasons for the development of such a facility are presented and the design requirements are given, mainly the pressure head-flow rate characteristics and the noise levels. The potential near future users are mentionned. A description of the Freon Pump Package is given including a lay-out, a mass breakdown, a system block diagramme, together with the design objectives and the design philosophy to achieve a very low level of noise. A special emphasis is given to the flow rate regulation modes which have been incorporated in the FPP design. The paper concentrates on the tradeoffs performed to select the main components of the pump unit which is the central active part of the FPP.

This paper addresses the temperature dependence of friction properties in seals (O-rings and D-rings) for use in reciprocating motions. The narrower focus here is on several factors: the effects of a lubrication state, the change in dimension and the physical properties of a rubber material. It can be assumed that they influence the temperature dependence of a frictional force. As shown in this study, A frictional force has a profile characterized by temperatures. It is revealed that the profile of a frictional force is mainly attributable to the deformation of a rubber material in motion-the physical properties (elastic modulus) of a rubber materials-and the rate of recovery in elasticity of a rubber material. In addition, a temperature showing the maximum frictional force is largely attributable to the low-temperature properties of a rubber material. It is revealed that the temperature dependence of a frictional force is mainly influenced by the material properties of rubber.

The important influence of engine friction on fuel economy has aroused new interest in its accurate measurement. Ricardo have developed a new system of instrumentation capable of measuring mechanical friction under any steady engine running conditions, and isolating the proportion of engine power absorbed by each of the auxiliary drives. Furthermore, auxiliary drive torque is measured instantaneously as a function of crank angle, enabling the dynamics of the drives to be studied. The instrumentation can be easily adapted to fit most engine types and configurations whilst retaining the original auxiliary drive design. Results obtained from gasoline and diesel versions of a 1.6 litre automotive engine using this instrumentation are described. Mechanical friction, pumping losses and auxiliary drive losses were measured with engine load, speed and coolant temperature varied.

General Motors and the Takata Corporation have worked together to bring to production a new, industry first technology called the Front Center Airbag which is being implemented on General Motors' 2013 Midsize Crossover Vehicles. This paper reviews field data, describes the hardware, and presents occupant test data to demonstrate in-position performance in far side impacts. The Front Center Airbag is an airbag that mounts to the inboard side of the driver front seat. It has a tubular cushion structure, and it deploys between the front seating positions in far side impacts, near side impacts and rollovers, with the cushion positioning itself adjacent the driver occupant's head and torso. This paper includes pictures of the technology along with a basic description of the design. In-position occupant performance is also described and illustrated with several examples. Single occupant and two front occupant far side impact test data are included, both with and without the airbag present.

Engine oil performance issues span a broad range of criteria, with the most often addressed including thermal and oxidative degradation control, anti-wear efficacy, contaminant suspension / dispersion capability, acid neutralization, maintenance of low temperature properties, and fuel economy retention. Each of these performance characteristics has an impact on the life expectancy of a lubricant. An additional factor that has been an area of ongoing research in this laboratory is the effect of fuel and fuel additives on the quality and performance of engine oils. It is recognized that fuel can reach the thin film of lubricant on the cylinder wall prior to combustion in an internal combustion engine. In this manner the base fuel constituents and fuel additives can enter the crankcase unburned. Laser induced fluorescence studies conducted previously demonstrated the delivery mechanism in an optically accessible gasoline powered engine (1).

The future emission legislations for diesel passenger cars are likely to include more dynamic test cycles than we have today, such as the World harmonized Light duty Testing Cycle (WLTC) and Real Drive Emissions (RDE) in the EU and very challenging SULEV legislations in the USA. In order to meet these emission legislations and challenging CO2 targets, more complex Exhaust Gas After Treatment Systems - EGATS and corresponding calibration strategies are needed. The calibration strategies have to provide the best possible fuel consumption and NOx emissions across the entire engine map for all tested cycles. The aim of this paper is to evaluate the effect of several EGATS configurations and calibrations on tailpipe NOx and CO2 emissions of a D segment vehicle. The experimental results and potential of various EGATS configurations and calibrations for the optimisation of fuel consumption and NOx emissions are presented and discussed.

In order to confirm friction and fuel economy performance of engine oils, laboratory bench tests, motored engine tests and chassis dynamo tests with HEV under WLTP were conducted. The fuel economy improvement effect of reducing viscosity and MoDTC were confirmed under these tests. Moreover, MoDTC (std.) exhibited excellent fuel economy improvement effect compared to MoDTC (L) under low temperature condition particularly. Low viscosity oils formulated with MoDTC (std.) showed superior fuel economy performance even at HEV with relatively lower oil temperatures in this study.

Knocking combustion limits the downsized gasoline engines’ potential for improvement with regard to fuel economy. The high in-cylinder pressure and temperature caused by the adaptation of a turbocharger aggravates the tendency of the end-gas to autoignite. Thus, the knocking combustion does not allow for further advancing of the combustion phase. In this research, the effects of the ignition and valve timings on knocking combustion were investigated under steady-state conditions. Moreover, the optimal ignition and valve timings for the transient operations were derived with the aim of a greater fuel economy improvement, based on the steady-state analysis. A 2.0 liter turbocharged gasoline direct injection engine with continuously variable valve timing (CVVT), was utilized for this experiment. 2, 10, and 18 bar brake mean effective pressure (BMEP) load conditions were used to represent the low, medium, and high load operations, respectively.

On April 6, 1984, EPA announced a final rule (40 CFR Part 600, Vol. 49, No. 68) which amended the Federal Fuel Economy Information Program by prescribing adjustment factors for the Federal fuel economy numbers and by establishing a new format for the Federal fuel economy label displayed on new vehicles. This rule, one of over 5, 000 documents printed in the 1984 Federal Register rule section, presents some interesting lessons about development of government regulations. The contents of this rule amended an existing rule, did not have a “major” impact on the economy, and was not considered to be controversial. Nonetheless, this rule represents at least nine years of work, negotiations, and deliberations by Federal and private sector organizations. The history of this rule can provide insight into the Federal rulemaking process, and the forces affecting that process.

Starting with the tractive energy requirements of vehicles over prescribed driving schedules, the fuel economy potential of idealised heat engine/flywheel hybrid vehicles was established as a function of vehicle characteristics and driveline efficiency. Both passenger cars and busses were considered in this analysis. The calculated idealized hybrid fuel economies were compared with cur rent production vehicle fuel economies and the potential for substantial fuel economy improvement was noted. When the hybrid vehicle is penalized for the initial flywheel-charge energy, the potential economy gains are reduced. The effect of the initial charge energy should not be neglected in passenger car driving schedules. However, the effect is minimal for the urban schedules typical of bus service.

The objective of this paper is to share the benefits regarding a study of fuel economy improvements involving Powertrain technologies. In this case our research was concentrated in vehicles transmissions initiatives like a Six Speed Manual Transmission application in Passengers Vehicles with low displacement engines. During the last 10 years the fuel economy challenges has presented a significant growth mainly due to two simple factors. First of all the fuel price which is the main driver to keep this technological continuous improvement. This fact has a direct influence in customers satisfaction, so all car makers concentrate huge efforts to provide intelligent solutions in order to increase competitiveness, as for example, the flex fuel engines (Figure 1). In parallel, the “green” appeal raises everyday stronger. Therefore the air pollution caused by vehicles gas emissions reinforces this commitment.

The new fuel injection method which is using the high-voltage electrical discharge has been proposed. The plasma jet ignition technology is applied to this injection system, and the component parts of fuel injector are similar to the plasma jet igniter. The purpose of this study is to elucidate the spray characteristics and the fuel injection development processes of this injection method. To obtain the influence of injector configuration and supplied electrical discharge energy on the fuel spray, the fuel is ejected into the open atmosphere and fuel injection development process is visualized by the schlieren method. The penetration depth, maximum width and projected area of fuel spay increase with increasing in the electrical discharge energy and an orifice diameter. In the case at which the large electrical discharge energy is provided, the fuel injection is finished within a short duration and the mean fuel spray velocity becomes fast.

Active engine-based measures are currently used to assist the exhaust aftertreatment. This paper presents the current predevelopment of a system for active exhaust aftertreatment of diesel engines which enables exhaust aftertreatment to be decoupled from engine-based measures. At the heart of the system, the Fuel Processor is the active component which is used to combust, reactively evaporate or partially oxidise the fuel, as required. Active catalytic converter heating, active particulate filter regeneration or heating of a SCR catalytic converter are possible without engine-based measures.

The paper describes an instrument developed for the purpose of quantitatively evaluating and registering individual injections in diesel fuel injection systems, and “quantity versus-rack” deliveries by a volumetric measuring method and electronic display or registration. The operating principle and construction of this quantity indicator are explained and the results of pertinent experimental tests are discussed.

A new laboratory technique is described which permits visual display and easy evaluation of the discharge characteristics of any given fuel injection pump at random nozzle back-pressure. In contrast to former fuel rate indication devices, the instrumentation is basically simple and lends itself to accurate calibration. Discussed are the basic underlying theory, the dimensional requirements for the measuring apparatus proper, and practical and theoretical applications of the new method on fuel injection systems. In conformance with the original dissertation, metric dimensions are used throughout.

This paper presents an investigation into global spray behavior and characteristics of injected spray from a High pressure Direct Swirl Injector (HDSI) at ambient conditions. Three types of swirler were designed at the initial development stage and they were used to analyze the relationship between tangential swirl port angle and spray characteristics. The swirler of the HDSI was designed based on these experimental results; being finalized with design of the valve seat and body. Using the “forward scattering image” method for visualization, the fuel and air mixing characteristics were assessed and laser diffraction was used to measure droplet size. Preliminary results regarding spray development showed that mixing increases with injection pressure. It was also found that the design of the swirler influences initial spray angle, and penetration length.