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The ROVAC air conditioning system, a new system that employs air as the refrigerant, is a combination rotary compressor/expander unit. A prototype has been modeled, designed, fabricated, laboratory tested, and field tested in a full size four door 1973 Dodge Coronet. The description of the new system, the analysis, design and actual test results are reported here. The objective of the engineering program was to demonstrate and prove the capability of the ROVAC system to effectively and efficiently air condition automobiles. The prototype system installed in the Dodge Coronet produces delivered cooling capacity on the order of one to one and a half tons per thousand rpm and has produced delivered coefficients of performance at relatively high humidity levels (150-180 grains water per pound of dry air) rivaling the best developed conventional vapor compression air conditioning systems.

The effect on radial passenger tire performance of the four most common belt materials-fiberglass, Kevlar, rayon, and steel-is discussed in light of their contributions to tread band stiffness. The magnitude of the material effects on performance is compared to the magnitude of belt geometric design effects on performance. It is demonstrated that the belt material differences do have a significant effect on performance related directly to how the material differences affect tread band stiffness. It is also shown that other design effects can overwhelm differences due to material differences alone.

The application of the P/M and P/F methods in the production of automotive parts was investigated and compared to the conventional methods of casting and forging, with special attention paid to the areas of cost and energy conservation. In relatively light parts weighing 200-500 grams, the use of P/M and P/F with pure iron powder resulted in a significant savings in both cost and energy consumption. In the heavier parts, however, this cost reduction was not realized because of the high cost for materials.

A theory of vehicle steering pull, created by asymmetrical tire cornering properties, is developed. It is validated with free control data obtained on the road. The effects of tire lateral force and aligning torque asymmetries on a car's straight line stability are analyzed for both fixed and free control. Equations for front axle lateral force, steering system moment, and sideslip angle are derived. They are based on tire properties and certain assumptions about the car's characteristics. This theory is validated using data obtained in open road testing. The test techniques, as well as alternate ones, are described. In addition, the relationships between actual front axle force and axle conicity force, ply steer force, and lateral force offset are analyzed. It is found that front axle conicity force correlates very strongly with a more accurate theoretical prediction. The axle force predicted by tire conicity force is somewhat low.

A steady-state, mass-transfer-limited monolith model has been formulated to investigate analytically the effects of gas-phase phenomena on converter performance. Gas-phase reaction kinetics are included to demonstrate the significance of noncatalytic processes to overall conversion, especially at temperatures above 850°K. Developing boundary layers in the monolith channels are shown to increase the calculated conversions relative to conditions for fully developed, laminar flow. Substantially different conversion efficiencies are predicted for various hydrocarbon species because of the effect of component diffusivity on convective mass-transfer rates. The expression for the gas-phase oxidation of hydrocarbons indicates that carbon monoxide forms as an intermediate product. Experimental evidence of carbon monoxide formation in conjunction with high concentrations of inlet hydrocarbons has been modeled with this partial oxidation reaction.

The effects of cell geometry and dimensions on the thermal shock resistance of catalytic monoliths is examined analytically. Two cell geometries, namely square and equilateral triangle, are considered. Thermal gradients predicted by theory compare well with the experimental results. It is found that for equivalent thermal shock resistance the triangular cell requires lower coefficient of thermal expansion than the square cell. Also, as the cell density is increased for higher geometric surface area, both geometries require a reduction in thermal expansion coefficient to preserve their thermal shock resistance. The above comparison does not take into account some of the other considerations which affect the overall performance, such as manufacturing advantage and the conversion efficiency. Also, the triangular cell examined has a cell density of 236/in2 with 20% greater geometric surface area than the square cell with a cell density of 200/in2.

An environmental burner rig test has been developed to support the development and evaluation of oxidation and sulfidation resistant alloys and coating systems. This test facility has been extensively utilized in the development of inherently sulfidation resistant alloys and the evaluation of various alloy/coating systems. Environment burner rig tests have shown that the simple aluminide coatings on C101 provide exceptional resistance to sulfidation attack. These alloy/coating systems are, in fact, competitive with some of the more expensive overlay coating systems.

Low temperature liquid nitriding is performed in a carbon and nitrogen fused salt bath as a single step hardening process. The two hour heat treatment produces substantial endurance and wear properties. Future planing for small size vehicles in the automotive industry includes low temperature liquid nitriding applications. Crankshafts, rocker arms, rocker arm shafts, camshafts, differential housings and gears all benefit from this specialized heat treatment. Cost advantages may be realized by low temperatre liquid nitriding of carbon steel as a substitute for alloy steels.

The results of two derivations relating to the fuel economy of hybrid-electric vehicles (vehicles which employ both a heat engine and electric drive system) are presented and their use is illustrated through the examples of the University of Wisconsin and TRW Systems Group hybrid-electric vehicles. The method of mileage estimation employs a specific fuel-consumption versus torque-speed map for the heat engine under study and knowledge of the hybrid-vehicle dynamics and road-load power. The method is easily extended to estimation of emission reductions through use of specific-emission-production versus torque-speed maps and is applicable to hybrid vehicles with other than electrical energy-storage systems.

The rapidly advancing technology in areas associated with battery-powered vehicle development is greatly enhancing the opportunities for such vehicles in the marketplace. However, the inherent inflexibility of such vehicles consistent with competitive economics of operation limits their possible applications. One such application has been identified by surveys and analyses in the Greater Manchester area as city center and conurbation public service vehicles, where up to 40% of duties can adequately tolerate the limited range of battery-powered vehicles within their method of operation. In order to evaluate the energy conversion efficiencies of a full size battery-powered bus, the Chloride Group in conjunction with the Greater Manchester Passenger Transport Executive has developed a prototype 50 passenger, 40 mph battery-powered vehicle named Silent Rider.

In-depth accident investigation programs in the past typically have not been addressed to specific research questions, nor have they been based on the principles of experimental design. This paper describes the design and implementation of an ongoing program for measuring the performance of the 1974 restraint system in actual crashes. Sampling techniques using a stratified systematic sample are used to compare the injury experience in 1973 and 1974 passenger cars. The design and implementation of the data collection and analysis as an integrated program are discussed, and preliminary findings are presented.

Recent surveys and investigations provide significant additional evidence that seat belts when worn can provide the greatest vehicle occupant protection of all currently available occupant restraint systems. Seat belts are effective and cost-effective, and are universally installed. Acceptable levels of seat belt usage can be attained through appropriate regulatory action requiring improvements in comfort and convenience of seat belt systems, and legislative action by the states to assure usage.

A presentation on zinc demonstrating its versatile applications to the auto industry. A review of metal balances, domestic, world and major producing countries. The energy required to mine, smelt and refine zinc is compared to other metals. The value of recycling zinc is also considered. This paper concludes with a statement, supported with evidence, that today's automobile is a better buy than twenty years ago.

This paper is an overview of the future aluminum metal supply situation, the aluminum industry's energy requirements and the potential for recycling aluminum from scrap autos. Within this framework, pricing, energy conservation and the industry's technological progress in the automotive field are also discussed.

The U.S. copper and brass industry has just demonstrated in a record-breaking production year (1973) its ability to supply mill products to meet customer needs in a period of high cyclical demand. The industry, in cooperation with its customers, is engineering ever more usefulness and value into each pound of copper used. New applications based on copper's unique combination of properties and on the changing needs of society are in the prototype stage of development. And at a time of upheaval in world markets, the U.S. can depend on its own self-sufficiency in copper-the earth's most recyclable resource.

A fleet of nearly 250 cars equipped with experimental catalytic converter systems were tested in taxi, police, state, and municipal fleets in various cities throughout the country. This provided a diversified range of customer service and altitude and climatic conditions. The objective was to evaluate the performance and durability in high mileage field service of experimental catalytic emission control systems. The fleet comprised groups of cars with hardware and calibration variations designed toward the 1975 Federal and California and more advanced emission requirements. The converter systems evaluated were primarily a 260 cubic inch underfloor converter and a 140 cubic inch manifold converter. Both bead and monolith substrate catalysts were examined. Test results showed that on the average the systems successfully controlled emissions to below the 1975 Federal and California requirements for greater than 50,000 miles.

Ruthenium-containing catalysts have good activity and selectivity for the reduction of the nitric oxides in automobile exhaust. Although designed to be operated under reducing conditions, these catalysts lose Ru by volatilization when subjected to lean transients. Attempts were made to stabilize these catalysts against volatilization by forming stable ruthenates. This paper deals with durability testing of stabilized ruthenate catalysts on a laboratory bench set-up, dynamometers, and vehicles. Post-mortem analysis of the durability-tested catalysts are presented showing the extent of stabilization. The results show that the Ru loss from ruthenate catalysts in present vehicle systems is in excess of acceptable limits. These losses can be minimized further, but at a cost of reduced selectivity in the NO reduction. Substantial further improvements are needed to achieve the required performance characteristics. Another problem is the poisoning by S, Pb and P.

The stringent 1978 emission standards of 0.41 gm/mi HC, 3.4 gm/mile CO, and 0.4 gm/mi NOx may require the use of a dual catalytic converter system (reducing and oxidizing catalyst). These emission requirements have been achieved at low mileage with such a system, but it is complex and has exhibited poor durability. This system also results in the loss of fuel economy at the 1978 emission levels.

Modern gas turbine engines with turbine inlet temperatures higher than metal melting temperatures must have control systems which provide subsecond response to changes in gas or metal temperatures. High quality data are required to provide for the most efficient engine operation consistent with engine safety. Recently developed instruments measure individual blade temperature; another non-immersion gas temperature sensor, not yet fully developed, will provide accurate gas temperature data up to 1900°C. These instruments are described with present and potential uses in control systems.