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The 3-D flow field inside an automotive torque converter was measured using laser velocimetry. For the tests, a torque converter completely machined from Plexiglas was operated at the 0.065 and 0.800 turbine/pump speed ratio, and detailed velocities were measured in 13 planes throughout the torque converter. Digital shaft encoder information was used to correlate measured velocities with the pump/turbine angular positions to generate blade-to-blade profiles, 3-D vector plots, and contour through flow plots. Results showed large flow separation regions, jet/wake flows, circulatory secondary flows, and significant flow unsteadiness in all three torque converter elements (pump, turbine, and stator). From the measured velocities, torque converter performance parameters such as mass flows, input/output torque, element incidence angles, slip factors, and vorticities were determined.

The introduction of the LDCR common rail injection system has opened up new possibilities in controlling the details of the injection rate and the spray characteristics. In particular, there is potential to optimize engine performance across the speed and load range, if a nozzle can be developed which has the facility to vary the final orifice area over the operating range of the engine. There are a number of different geometries which may achieve the required effects. Two possible methods are to throttle either the entrance or the exit of the nozzle holes to a greater or lesser extent, according to the engine running condition. The paper describes an investigation of the spray characteristics of entry and exit throttled orifices, and how they are affected by pressure levels and degrees of opening. In previous studies, large scale transparent models have accurately reproduced the different spray characteristics observed with actual nozzles.

The flow reversal chamber is a commonly used element in practical silencer design. To lower its fundamental eigenfrequency, it is suggested to acoustically short circuit the inlet and outlet duct. In the low frequency limit such a configuration will correspond to a Helmholtz resonator, but with a choked flow through the short circuit, the main flow will be forced through the expansion volume. For the proposed concept, the flow reversal resonator, a theoretical model is derived and presented together with transfer matrix simulations. The possible extension to a semi active device as well as the influence of mean flow on the system is investigated experimentally. Finally the concept is implemented on a truck silencer. The results indicate that the flow reversal resonator would prove an interesting complement to traditional side branch resonators. The attenuation bandwidth is broader and it can be packaged very efficiently.

A flow visualization study of the louvered fin geometry, commonly used in automotive heat exchangers was performed. Flow visualization was performed using a dye injection technique with 10:1 scale models. The geometrical parameters, louver pitch, louver angle, and fin pitch were varied to determine their effect on the flow structure. Tests covered louver pitch based Reynolds numbers of 400 - 4000. Data are presented in the form of a dimensionless flow efficiency (defined in terms of the mean flow angle, relative to the louver angle) and Reynolds number. Correlations are developed to predict the flow efficiency as a function of dimensionless geometrical groups and Reynolds number. A discussion of the flow structure is also presented.

With its advantages on cost and performance, the integrated exhaust manifold (casting with the turbine) is being used on more vehicles by auto makers. Generally, when compared with the divided exhaust manifold, the integrated exhaust manifold stands for higher vibratory excitation from gas dynamics. In this paper, the gas dynamics excitation has been computed through the GD (gas dynamics) software GT-Power which calculates the exhaust pipe surface pressure, and CFD code Star-CCM+ which calculates the turbine blade force. And the response of manifold has been solved under this excitation. On the other hand, the mechanical excitation has been computed through the MBD (multi-body dynamics) platform AVL-Excite-PU, and the responses under the gas excitation plus the mechanical load have been studied in order to analyze the effects of the fluid excitation on an integrated manifold.

A new high energy impact hammer incorporating a fluid tappet and a high velocity piston is described which offers improved productivity, safety and reliability in rock excavation, structure demolition and secondary boulder breaking. Two models of this hammer are discussed, the 411 with a blow energy of 6000 ft. lb. (685 kg.m.) and the 514 with 20,000 ft. lb. (2275 kg.m.). The attachment of these new tools to a wide range of excavators and special machines is shown. The process of impact breaking is analyzed and several examples of effective use of these hammers are presented.

Material, processing, and development experience with vacuum brazing of aluminum radiators is reviewed. The welded, clad tube and bare fin concept is shown to be economically and technically superior to other designs. The mechanisms of vacuum brazing and process requirements are reviewed as they apply to radiators. Individual components and joint areas are examined to illustrate solutions to specific problems.

Our concept studies indicate that a set of reflectors floated in the upper atmosphere can efficiently reduce radiant forcing into the atmosphere. The cost of reducing the radiant forcing sufficiently to reverse the current rate of Global Warming, is well within reach of global financial resources. This paper summarizes the overall concept and focuses on one of the reflector concepts, the Flying Carpet. The basic element of this reflector array is a rigidized reflector sheet towed behind and above a solar-powered, distributed electric-propelled flying wing. The vehicle rises above 30,480 m (100,000 ft) in the daytime by solar power. At night, the very low wing loading of the sheets enables the system to stay well above the controlled airspace ceiling of 18,288 m (60,000 ft). The concept study results are summarized before going into technical issues in implementation. Flag instability is studied in initial wind tunnel experiments.

A summary of The Flying Tigers’ experience with the Canadair Forty-Four is presented. Capabilities and specifications of the aircraft are given, as are its advantages over other types of craft. Operating problems and their solutions and operating costs are also discussed.

Flywheel energy storage systems (FESSs), commonly know as flywheel batteries, are being developed for a number of power averaging applications in the transportation industry. Most FESS designs incorporate rotors made from composite materials for which operating experience is limited and little failure data is available. Given the high energy levels inherent in these devices, a major task for the FESS designer is to provide adequate containment structures to insure safe operation in the event of flywheel failure. This paper discusses ongoing work intended to provide a better understanding of composite flywheel failure mechanisms and development of a methodology for safe containment design.

The International Space Station (ISS) has been continuously crewed for more than 2 years. One of the major systems for crew health, performance and psychological support is the food system. This paper documents the mechanics of implementation for the ISS food system, with emphasis on the U.S. portion of that system, and also provides some performance feedback received from the first 5 increment crews. Menu composition and planning, food stowage, on orbit preparation, shipments, and inventory control are also described.

Sales of diesel passenger cars and car diesel derived vans has grown steadily in Western Europe throughout the 1980's and currently stands at some 16 percent of the West European Car market. The major advantages of the diesel are its excellent fuel economy and low gaseous emissions. Excellent fuel economy, together with lower fuel costs in some markets, results in low operating costs when compared to comparable petrol engined vehicles. The low gaseous emissions of the diesel become increasingly attractive as environmental pressures increase, particularly the low CO2 emissions which will be of increasing importance in the debate over the global ‘greenhouse effect’. As the diesel market increases customer expectations become more critical. Given the diesels benefit of low operating cost and low emissions, the customer also expects levels of refinement (noise, vibration and harshness) and performance feel to be similar to those of the comparable petrol engined vehicle.

The most important target in the development of the first Ford passenger car Diesel engine was fuel economy. Also required were a compact engine package to allow installation in small cars, a robust design for long engine life, and a configuration suitable for further development. Specific design features in the cylinder head and fuel injection pump drive contribute to durability and packageability, and detailed development of the combustion chamber design, gas exchange process, and fuel injection equipment has resulted in excellent fuel economy. (1)

The FORD 2.5 Litre DI Engine entered volume production in January 1984, as the World's first high speed naturally aspirated direct injection diesel. Producing 52 KW at 4000 RPM the engine achieves a 15% fuel saving over indirect engines of similar size and rating. The direct injection engine is inherently less thermally active than pre-chamber engines and this, together with other design features, provides a power unit with extended durability for the medium van market. Based on controlled swirl air management, the otherwise conventional combustion system depends heavily on the fuel injection system for control throughout the speed load and temperature ranges. This paper describes the key elements of the design and performance development of the 2.5 litre DI engine, discusses the experience gained and examines the possibilities of a second generation of engines based on this system.

Continuing demands for performance improvements in passenger car engines led to the development of the Ford 427 cu in. single overhead cam engine. See Fig. 1. Author discusses manner in which development of this engine was accomplished, using several design parameters, which included new and previously proved features.

A small-scale oxidation test for automatic transmission fluids has been developed. In the test air flow rates, temperature and catalytic activity can be closely controlled at desired levels. A test procedure for screening automatic transmission fluids is described. Data are presented illustrating the ability of the test to distinguish between different levels of oxidation resistance, the repeatability of the test, and the correlation achieved thus far with a presently used full-scale transmission oxidation test.

FORD'S answer to the air suspension problem is a system of the “open” type in which the air is exhausted from the springs to the atmosphere. It features a 2-speed automatic height and leveling control to handle differing load conditions. In adapting the air springs to the suspension arms, the front suspension was modified only slightly, while the rear was completely redesigned. The author reports that a significant improvement in passenger comfort has been achieved with the new suspension, especially for the rear seat passenger. Also, the car height remains constant under all loadings—a contribution to the car's appearance.

The history of electric car evolution and the reasons for the design of this experimental city car are reviewed. Chassis, body, and electric power train designs are described. The performance of key electric car components and the vehicle as a whole is discussed. A detailed description of the electric control components is contained in the Appendix.

This paper describes the design and development of the Ford Driving Simulator. The simulator is a fixed-base device which provides real-time, interactive feedback to the driver through a combination of visual, auditory and tactile cues. The system is comprised of a modular buck, 150° field-of-view visual scene, a steering torque controller, high fidelity dynamics models, and an interactive experimenters station. Data acquisition systems have been developed to capture a broad spectrum of driver performance metrics.