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Engine deposits and wear are greatly affected by engine oil-additive treatment variables and by engine-operating parameters, such as oil-change interval and oil filtration. While each of these two major elements has been investigated extensively, little is known about interactions between these elements. Tests with 1963-1967 model United States passenger cars, operating with leaded commercial gasolines in several types of service, evaluated effects on deposits and wear of: 1. Ashless (nonmetallic) dispersants. 2. Zinc dialkyldithiophosphate (ZDP) type and concentration. 3. Interactions between dispersant and ZDP. 4. Interaction among dispersant concentration, oil-change interval, and supplementary bypass oil filtration. Sludge and varnish deposit control differed widely among three dispersants used at equal concentrations. Increasing the concentration of the best dispersant reduced sludge but not varnish.

While oxygen sensors provide the means by which changes in exhaust gas AFR (air-to-fuel ratio) are monitored and controlled in three-way catalyst systems, the chemistry of the exhaust gas in contact with this solid state electrochemical sensor can exert a substantial influence on its AFR control performance. Such interactions have been examined in a fundamental study on commercial oxygen sensors (unheated and heated), firstly using simple gas mixtures, and then simulated exhaust gas mixtures of progressively increasing complexity. The work confirms that diffusion effects at the sensor surface are centrally important in determining sensor response, but indicate that the effects of H2 (the smallest species present) do not necessarily dominate the observed behaviour. The results allow the development of a relationship that can be used to estimate the extent of the expected overall lean or rich shift for the sensor as a function of the exhaust gas composition.

Due to increasingly higher application demands, engine and transmission manufactures are today using lubrication oils with more and more additives. The result is that seal materials are being damaged when exposed to such conditions and such additives. This work will show the effects of basic oils with, and without, additives on elastomeric materials such as NBR. ACM, MVQ and FPM.

The paper describes the interactions between the filler material and the copper fin in the joint in the CuproBraze® process. Due to the influence of the filler metal, part of the copper fin is alloyed. The influence of the time above the melting point of the filler material and of the maximum process-temperature were investigated. It was found that the time has the strongest influence. After laboratory tests and production scale tests a brazing window for the process has been established. That can be used to set up brazing cycles for different kind of furnaces. From a number of wind tunnel tests it has been confirmed that when the brazing is done within this window the alloying of the fin is limited that it does not have practical influence on the thermal performance of the heat exchanger.

The European diesel fuel specification limits the biodiesel content to 7 %. It is, however, desirable to increase the amount of renewables in the transport sector; therefore blending with a higher biogenic fuel content is of interest. Blending of fuels can lead to chemical reactions between fuel components and may result in undesired products. In detail, aged biodiesel from unsaturated FAME and fossil diesel fuels can form oligomers and precipitations with a maximum in the range of B10 to B20. Precursors are oligomers that can be separated from the biodiesel or the blends in an amount of up to 20 %. These oligomers are soluble in the fuel, but they seem to have potency for chemical reactions with fuel components or the engine oil. To prevent tentative problems in the fuel filter, the injecting system and the combustion process itself, the formation of oligomers should be disabled in blends. Alcohols have been proven and tested to dissolve precipitations in the fuel.

Discomfort glare from vehicle lighting is more difficult to measure precisely than disability glare, but may have important implications for driver behavior, and in turn on driving safety. Many studies of discomfort glare have found that, as with disability glare, the illuminance at the eyes from a bright light is the primary determinant of the sensation of glare. Nonetheless, the luminance of a light source also can influence discomfort glare, especially when the source is close enough to subtend a relatively large visual angle on the order of a third of a degree or larger. In addition, interactions with the absolute illuminance from a light source are not well understood. The results of an experimental investigation of discomfort glare in terms of light source illuminance, luminance and size are presented and discussed along with implications for automotive lighting applications.

A two-stroke diesel engine was outfitted for operation with an electronic solenoid-controlled unit injector and an additional solenoid-controlled air-assisted injector at the inlet ports. Factorial experiments were designed in order to quantify, in a statistically representative manner, the effects of pilot (or ‘split’) and port auxiliary injection on main fuel combustion. Results indicated that interactions between experimental parameters (such as between pilot fuel quantity and pilot-to-main spacing), as well as main effects are important in analyzing auxiliary fuel injection. The bulk gas temperature at main injection was determined primarily by the experimental parameters acting independently of one another, which is a case where main effects only are important. Conversely, analysis of indicated specific fuel consumption and peak cylinder pressure involved interactions of the experimental parameters in both cases.

During railway braking, dissipation of high energy due to friction leads to transient and localised thermal phenomena such as hot bands and hot spots. These localisation phenomena interact with third body flows and friction mechanisms activated in the contact. To study these couplings, an experimental approach has been developed, based on an inertial tribometer able to reproduce high thermo-mechanical brake-disc loadings. This paper focuses on the coupling between flows of third-body and hot-band migration. Transient localised thermal phenomena are described for high-energy stop-braking. The monitoring of the disc track during friction in the visible and infrared wavelengths evidences the interactions between third-body flows and hot-band migration.

Binaural recordings are often used for added realism in subjective listening studies, but are commonly played back in environments that are different than those in which the recordings were taken. An important component of the added realism is the ability of the listener to locate the acoustic sources in a three dimensional space. While humans can generally do a good job of locating acoustic sources through inter-aural time differences (ITD) and inter-aural intensity differences (IID), some well documented ambiguities exist when using these acoustic cues by themselves (i.e. ITD and ILD for a source in front of or behind a listener are identical). To resolve these ambiguities, humans often rely on supplemental information from either direct visual feedback or from their knowledge of and comfort with the listening environment.

Automotive lubricating oils consist of base oils and a variety of chemical additives. In this study, interactions among an antioxidant (ZDDP), a dispersant (succinimide), and a detergent (calcium sulfonate) are studied in terms of oxidation stability. Oxidation tests were conducted at 60 °C and 160 °C using the free radical titration test and the thin film oxygen uptake test respectively. Complex chemical interactions in terms of oxidation stability were found among the additives, as well as the additives with the polar species in the base oil. Optimum oxidation concentrations for some of the additives were observed. The effects of temperatures on the interaction were also described.

An experimental investigation of the effects of injector type and orientation, engine speed, in-cylinder air swirl, compression pressure, and fuel type has been conducted in motored visualization engines. A fuel-spray visualization system has been developed and utilized to obtain high-speed stroboscopic movies of the injection and penetration events. Significantly different interactions between the fuel spray and the in-cylinder air motions were found to result from changes in air-swirl ratio, nozzle geometry and injection timing. The maximum spray-tip velocity was found to occur downstream from the injector tip for all conditions tested. For applications requiring minimum fuel-spray penetration, the impinging-jet injector was found to be the most promising candidate.

Slush molded PVC instrument panel skins interact with the flexible urethane foam backing. This interaction is accelerated by the light and heat present in the automobile interior, and may result in discoloration, shrinkage and general hardening of the instrument panel. New low stain urethanes have been introduced, which reduce the severity of these problems. These foams, when coupled with recent developments in PVC skin compounds, may produce significant improvements in long term durability of instrument panels.

Advanced valvetrain coupled with Direct Injection (DI) provides an opportunity to simultaneous reduction of fuel consumption and emissions. Because of their robustness and cost performance, multi-hole injectors are being adopted as gasoline DI fuel injectors. Ethanol and ethanol-gasoline blends synergistically improve the performance of a turbo-charged DI gasoline engine, especially in down-sized, down-sped and variable-valvetrain engine architecture. This paper presents Mie-scattering spray imaging results taken with an Optical Accessible Engine (OAE). OAE offers dynamic and realistic in-cylinder charge motion with direct imaging capability, and the interaction with the ethanol spray with the intake air is studied. Two types of cams which are designed for Early Intake Valve Close (EIVC) and Later Intake Valve Close (LIVC) are tested, and the effect of variable valve profile and deactivation of one of the intake valves are discussed.

The objectives of this study were to examine the response, repeatability, and injury predictive ability of the Hybrid III small-female dummy to static out-of-position (OOP) deployments using a depowered driver-side airbag. Five dummy tests were conducted in two OOP configurations by two different laboratories. The OOP configurations were nose-on-rim (NOR) and chest-on-bag (COB). Four cadaver tests were conducted using unembalmed small-female cadavers and the same airbags used in the dummy tests under similar OOP conditions. One cadaver test was designed to increase airbag loading of the face and neck (a forehead-on-rim, or FOR test). Comparison between the dummy tests of Lab 1 and of Lab 2 indicated the test conditions and results were repeatable. In the cadaver tests no skull fractures or neck injuries occurred. However, all four cadavers had multiple rib fractures.

A new, simple approach to general planar mechanism analysis has been developed which is intended for use with interactive graphic display terminals. This approach can be applied to 80 percent of the mechanisms used in earthmoving equipment. It allows even complex machanisms with multiple external loadings to be analyzed quickly, in small amounts of core. This paper describes the method for modeling a mechanism and the procedure for finding its new positions. Velocity, acceleration, and static force analysis techniques are presented and illustrated by example mechanisms. Not only are these procedures basic and logical, they are also repetitive from pin to pin on the linkage, which makes them easy to program.

Interior vehicle sound is an important factor for customer satisfaction. To achieve an optimized product sound at an early stage of development, subjective evaluation methods as well as analysis and prediction tools must be combined to provide reliable information relevant to product quality and comfort judgments. Binaural Transfer Path Synthesis (BTPS) is a well-known method to calculate interior noise and vibrations based on multi-channel input measurements. Recent enhancements of the BTPS method enable taking into account also simulated excitations, for example engine mount vibrations calculated using MBS and/or FEM simulations, allowing the prediction of interior noise even if the engine is not available in hardware. Interactive evaluation of the generated sounds in a vibro-acoustic driving simulator helps to increase understanding of customer responses and perception of target sounds.

The on-orbit performance verification of the functions constituting a Space Manned System is one of the critical points of space projects. During phase C/D of Node 2 & 3 and ATV Space station modules, the Alcatel Alenia Space - Italia approach for the verification of the design requirements related to the correct air distribution inside the Module habitable volume was to use a CFD virtual mock-up, derived by CAD models. These models were correlated with existing on ground ventilation tests and were extensively used during the project phase to evaluate the impact on the relevant ventilation requirements of possible internal module layout changes and item relocations. This paper describes the developed tool capability and presents the results obtained in support to the Assembly, Integration and Test (AIT) phases.

In industries such as aerospace, automotive and shipbuilding, various mathematical models are used for the computer internal representation of curves and surfaces. Most of these industries have recently adopted B-Spline curves and surfaces to take advantage of their outstanding properties. The B-Spline technique provides a high degree of flexibility in that it allows any order of continuity, including controllable discontinuity and local deformation ability. Compared to other methods, a B-Spline requires relatively little storage space and permits efficient evaluation, allowing direct manipulation of a curve or surface on an interactive graphics device. The educational computer program B.SPLINE was designed to introduce designers to the B-Spline technique. B.SPLINE enables the user to generate and manipulate B-Spline curves using “rubber banding” on an Apollo computer.

An interactive computer graphics program has been developed to help in vehicle design. The most important aspect is the use of a highly interactive interface between the user and the underlying analytical model. This allows for a closed loop design process and enhanced communication in both directions, both to and from the program. The paper discusses how the program helps the user visualize the many facets of vehicle behavior, how the user can easily change the parameters of the vehicle, and how dynamic transient response is simulated.

Computer simulations of vehicle dynamics can be a useful investigative tool in drive-ability and NVH studies. As the present work demonstrates, oscillations of the drive-train under steady-state and transient conditions are amenable to mathematical analysis, especially in the torsional mode. Simulations of such a system with a lock-up torque converter are shown with emphasis on tip-in response, transmissibility of engine firing pulsations and self-excited oscillations. In particular, the method of interactive simulation is shown to be an effective design-aid tool in the investigation of drivetrain vibrations.