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Technical Paper

Zeroshift Automated Manual Transmission (AMT)

Zeroshift technology allows a manual transmission to change gear in zero seconds. The Zeroshift Automated Manual Transmission (AMT) is easy to manufacture and allows a cost effective alternative to the traditional torque converter based automatic transmission. Zeroshift offers potential fuel economy improvements from driveline efficiency and the best possible vehicle acceleration. Compared to an existing AMT, Zeroshift offers an uninterrupted torque path from the engine to vehicle which allows for a seamless gearshift. This seminal paper provides an introduction to the technology together with test data from a demonstrator vehicle.
Technical Paper

Zeroshift. A Seamless Automated Manual Transmission (AMT)With No Torque Interrupt

Zeroshift technology allows a manual transmission to change gear in zero time. The Zeroshift automated manual transmission (AMT) is easy to manufacture and allows a cost effective alternative to the traditional torque converter based automatic transmission. Zeroshift offers potential fuel economy improvements from driveline efficiency and the best possible vehicle acceleration. Compared to an existing AMT, Zeroshift offers an uninterrupted torque path from the engine to vehicle which allows for a seamless gearshift. This paper provides an introduction to the technology together with test data from a demonstrator vehicle.
Technical Paper

Zinc Alloy Engine Components

The ZA series of zinc alloys produce high strength die castings with the same cast-to size capability as the well proven SAE 903 alloy. The enhanced properties have been utilised in the two engine components described in this paper. ZA 27 has been used for the tooth belt drive camshaft pulley of a motorcycle engine and ZA8 has been used for the temperature resistant housing of a car ignition distributor.
Technical Paper

Zinc Distribution in Vacuum Brazed Alclad Brazing Sheet

Vacuum brazing technology is currently capable of producing aluminum automotive heat exchangers such as radiators and heater cores. The possible use of 7072 claddings on the surfaces exposed to the coolant to provide additional corrosion protection is of considerable interest. This paper describes the effect of typical vacuum brazing cycles on the distribution of zinc in 7072 clad vacuum brazing sheet. For heavier gauges (.05″), there is sufficient retained zinc in the post-braze composite. For lighter gauges (.02″ or less), nominal composition 7072 does not provide adequate retained zinc; however, if the initial zinc concentration is increased to 3% there is sufficient retained zinc so that the cladding is significantly more anodic than the core.
Technical Paper

Zinc Soldered Copper and Brass Radiators: Their Processing and Their Test Results

Copper and brass radiators have served the automobile industry for many years using traditional fabrication processes. Demand for newer and stronger radiators with lighter weight for the modern vehicles prompted investigation of alternate materials. Properties of zinc alloys and their compatibility with brass suggested these could be used for radiator manufacture. Many zinc alloy compositions were investigated in the initial studies, because a solder alloy has to have many positive attributes. The first screening studies evaluated the ability of the solder to spread over copper and brass surfaces, representing tube, fin, and header materials. The second most important feature was the melting range of the developed alloy. In order to retain the anneal resistance of the fin and temper in the tube it was desirable to have a zinc solder with a melting temperature at 800°F or less.
Technical Paper

Zinc-Air Batteries for Electric Vehicles

This paper describes a design for an electric vehicle (EV) battery system using a secondary (rechargeable) lead-acid section for power and a recyclable (mechanically replaced) primary zinc-air section for range. This approach optimizes the performance of each battery, resulting in a system with driving performance (acceleration, range, and refueling time) equal to that for internal combustion vehicles (ICVs). The physical characteristics of the system's components are highly compatible with their ICV counterparts, resulting in a substantial reduction in the cost of building prototype vehicles. The overall cost of the rechargeable/recyclable approach is estimated to be equal to that for the traditional single rechargeable battery approach.
Technical Paper

Zirconia Based Ceramic, In-Cylinder Coatings and Aftertreatment Oxidation Catalysts for Reduction of Emissions from Heavy Duty Diesel Engines

Diesel engines are coming under stricter requirements to reduce emissions. particularly those of particulates and nitrogen oxides (NOx). Recently, the U. S. EPA put into place staged requirements for heavy duty diesel engines in urban bus applications which are aimed at ultimately bringing pre-1994 engines into particulate emissions compliance with 1994 heavy duty on-road truck standards (0. 1 g/bhp-hr TPM). This reflects the need to control emissions in crowded urban environments. Zirconia based ceramic combustion management coatings, although originally developed for adiabatic or low heat rejection engines to boost thermal efficiency, have also been shown to contribute to the reduction in diesel emissions. Heavy duty transient testing of rebuilt 2-stroke MUI diesel bus engines equipped with stabilized zirconia based coatings applied by thermal spray process have shown significant reduction in exhaust opacity relative to a baseline, uncoated engine.
Technical Paper

Zoonoses and Enclosed Environments

The likelihood of transmission of potential disease agents between animals and man during spaceflight is a real concern. Development of disease exclusion lists for animals and refinement of animal containment units have been the principal means of providing protection to the crew members. Awareness of potential latent infections and a judicious use of the higher risk category of animals such as wild-caught nonhuman primates provides another level of protection. Use of high efficiency filters, gasketing, and differential air pressures have all enabled increasing levels of safety through containment of potential aerosol escape from animal habitats.

Zwick Roell provides flexible materials testing over a wide temperature range

To enable the tests required for development work to be performed with maximum efficiency, the Zwick Roell Group (ZwickRoell) – a global supplier of materials testing machines based out of Ulm, Germany – developed a materials testing machine that can be equipped with both a temperature chamber and a high-temperature furnace.
Technical Paper

a new look at High Compression Engines

THE automotive and petroleum industries have been concerned for many years with the mutual problem of improving the thermal efficiency of gasoline engines. Great progress in refining technology, as well as advances in engine design in recent years, have made it desirable to take a new look at high-compression engines. This paper describes an investigation of the effect of compression ratio on engine efficiency over a range of compression ratios from 9/1 to 25/1. The results show that the thermal efficiency of the multicylinder engines used in this study peaked at a compression ratio of 17/1. The decrease in thermal efficiency at higher compression ratios is due primarily to delay in the completion of the combustion process. This paper received the 1958 Horning Memorial Award.
Technical Paper

a progress report — Dry-Type Air Cleaners on Farm Tractors

GREATER ease of servicing is one of the ultimate goals in the development of dry-type air cleaners. The authors acknowledge, however, that the oil-bath cleaner is a rugged proved component that has done a good job for the farmers who serviced it properly. This paper describes studies made in Illinois of oil-bath and dry air cleaners in field service. At the same fuel/air ratios, the maximum horsepower of a test engine was greater with the dry-type filter than with the oil-bath cleaner. It was found that with AC fine dust and steady airflow, the oil-bath cleaners had significantly lower efficiencies than the dry-type filter. At less than rated airflow the efficiency of the oil-bath cleaner decreased while that of the dry filter remained high.
Technical Paper

a study of Self-Contained Starting Systems for Turbojet and Turboprop Engines

SUBSTANTIAL POWER is necessary to start the modern jet engine. Thus, starting equipment has become a major concern of air transport operators. This paper discusses the equipment used with self-contained starting systems. The authors discuss and evaluate a variety of self-contained systems: combustor, fuel-air combustion, cartridge, liquid propellant, hydraulic supported by auxiliary power units, and electric supported by APU. Possible future systems are: self-breathing systems, oxygen combustors, and liquid-oxygen-water-fuel combustors. It is emphasized that the choice of a starting system for a particular aircraft will depend on aircraft characteristics and the aircraft's intended use.*
Technical Paper

a universal means for Rating Diesel Engines for Deposits and Wear

THE NEW CRC Diesel Engine Rating Manual is intended to furnish a universal language for identification of diesel-engine deposits and wear. Diesel-engine pistons are evaluated for lacquer deposits by utilizing an area demerit basis and color gradations of brown and gray from clean to black. In studying various means for evaluating thickness and texture of deposit in oil systems, it was decided that the scratch gage developed by the CRC Engine Deposit Rating Panel of the CRC-Motor Engine Varnish and Sludge Group was suitable for diesel engines. A procedure for establishing a volume factor which furnishes a weighted interpretation of the deposit was created.*
Technical Paper

an evaluation of AFTERCOOLING in Turbocharged Diesel Engine Performance

AFTERCOOLING, coupled with higher pressure turbocharging can increase vehicle engine output. The author thinks that it is possible to anticipate diesel engines being run with compressors supplying air at pressure ratios higher than 2/1. Density ratio is the most important consideration in increasing pressure ratio, since the engine's output is dependent upon weight rather than volume of air supplied. Because the density of the compressed air is dependent upon its temperature at any pressure level, cooling the air after compression results in density increases. This paper describes various methods of after-cooling which increase engine output and fuel economy.
Technical Paper

and Repeatability of Transient Heat Release Analysis for Heavy Duty Diesel Engines

Reduced emissions, improved fuel economy, and improved performance are a priority for manufacturers of internal combustion engines. However, these three goals are normally interrelated and difficult to optimize simultaneously. Studying the experimental heat release provides a useful tool for combustion optimization. Heavy-duty diesel engines are inherently transient, even during steady state operation engine controls can vary due to exhaust gas recirculation (EGR) or aftertreatment requirements. This paper examines the heat release and the derived combustion characteristics during steady state and transient operation for a 1992 DDC series 60 engine and a 2004 Cummins ISM 370 engine. In-cylinder pressure was collected during repeat steady state SET and the heavy-duty transient FTP test cycles.
Technical Paper

basic design of Turbochargers for diesel engines

ALTHOUGH turbocharging of low-speed diesel engines has been used world-wide for a long time, it is only during recent years that it has been applied to high-speed diesels. This is the result of considerable engineering efforts from both the turbocharger and the diesel side that were put into the turbocharger, which appears to be a so utterly simple device. This paper de­scribes some of these engineering efforts. The basic design characteristics are developed with the point of view in mind that the turbo­charger has become much more than just an ad­ditional accessory. It is a vital component of the basic engine itself, contributing actively to the advancement of this prime mover. The basic de­sign characteristics center heavily around aero­dynamical and thermodynamical performance cri­teria which are so important in any advanced high-speed turbomachine.
Technical Paper

considerations of some JET-DEFLECTION PRINCIPLES for - - directional control - - lift

THE performance characteristics of various devices applicable for jet directional control, lift augmentation, and VTOL-STOL studied at the NACA Lewis Laboratory are discussed, including jet deflection devices applicable to the conventonal round nozzle and novel nozzle configurations. The results indicate that many of the deflection devices applicable to conventional nozzles can readily be used for directional control or lift augmentation. Other deflection devices, such as movable plug, internal flap, cylindrical thrust reverser, swiveled primary with fixed shroud, and 90 deg side-bleed nozzle, are limited in application to jet directional control or aircraft trim because the loss in axial thrust for a given deflection force is prohibitive or the maximum deflected force obtainable is limited.
Technical Paper

development of two new Allis-Chalmers Diesel Engines

THE NEW DIRECT-INJECTION diesel engines — the naturally aspirated 16000 and the turbocharged 21000 — were developed to power specific crawler and wheel vehicles built by Allis-Chalmers. Thus the original design and performance specifications were defined by the space available in these machines, and by the power and torque characteristics required by them. Also, the engines had to be suitable not only for commercial applications such as generator sets, shovels, and compressors, but also for oil field and marine service. Torque and speed requirements indicated that a 5¼-in. bore and 6½-in. stroke would give the desired performance. To meet the low heat rejection and good starting requirements, an open-chamber combustion system had to be used. The three-valve arrangement — two intake and one exhaust — was chosen because it offered low pumping losses and reasonable cost. This paper describes the design considerations and development work which produced the new diesel engines.*
Technical Paper

e Vehicle Cooling System Approach for off-highway machines

Traditionally the off-highway vehicles like tractors, construction and road building machinery have been using diesel engine as the power source. In recent times there has been more and more focus to adopt either all electric or hybrid powertrain for off highway vehicles to reduce the carbon footprint. The e machines involve various electrical components like Battery pack, On board Charger, DCDC converter, Inverters, Traction motors, PTO Motor and e transmission. The cooling requirement and the fluid temperature limits for these electric components is different compared to the conventional diesel engine. In most of the cases the battery cell temperature needs to be around 20 to 30 °C which in most cases would be below the ambient temperature. Whereas the hydraulic oil temperature can be as high as 100 °C. The hydraulic oil temperature can be maintained using a separate air-cooled hydraulic oil cooler or a plate cooler.
Technical Paper

e-Thermal: A Vehicle-Level HVAC/PTC Simulation Tool

This paper describes a vehicle-level simulation model for climate control and powertrain cooling developed and currently utilized at GM. The tool was developed in response to GM's need to speed vehicle development for HVAC and powertrain cooling to meet world-class program execution timing (18 to 24 month vehicle development cycles). At the same time the simulation tool had to complement GM's strategy to move additional engineering responsibility to its HVAC suppliers. This simulation tool called “e-Thermal” was quickly developed and currently is in widespread (global) use across GM. This paper describes GM's objectives and requirements for developing e-Thermal. The structure of the tool and the capabilities of the simulation tool modules (refrigeration, front end airflow, passenger compartment, engine, transmission, Interior air handling …) is introduced. Model data requirements and GM's strategy for acquiring component data are also described.