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The Chevrolet Volt is an electric vehicle (EV) that operates exclusively on battery power as long as useful energy is available in the battery pack under normal conditions. After the battery is depleted of available energy, extended-range (ER) driving uses fuel energy in an internal combustion engine (ICE), an on-board generator, and a large electric driving motor. This extended-range electric vehicle (EREV) utilizes electric energy in an automobile more effectively than a plug-in hybrid electric vehicle (PHEV), which characteristically blends electric and engine power together during driving. A specialized EREV powertrain, called the "Voltec," drives the Volt through its entire range of speed and acceleration with battery power alone, within the limit of battery energy, thereby displacing more fuel with electricity, emitting less CO₂, and producing less cold-start emissions than a PHEV operating in real-world conditions.

This paper consists of a brief history of the origin of the Sealectors and Sealraters, a description of the more popular models of machines, their capabilities, and the improvements made since their conception. The Sealectors are air gaging machines for measuring the inside diameter and the lip opening pressure of lip type shaft seals. The machines are available as laboratory models or as semiautomatic bench type or fully automatic models for production testing of seals. The Sealraters are machines for endurance and performance testing of lip type shaft seals under simulated conditions encountered in their application. The Sealraters are generally used as laboratory equipment for determining specifications to be applied to seals.

The Sealometer is used for evaluating the performance of lip type oil seals and provides a dimensionless number derived from measuring the increase in temperature of a test shaft operating in a lip seal for a given time interval. With the Sealometer it is possible to study parameters that affect seal performance. As a quality control instrument, the machine provides accurate data for design. Sealometer evaluation offers a quick method of determining the life expectancy of a particular design for a particular application and eliminates the need for long life test programs.

This paper summarizes the history and most significant accomplishments of the GMR-GMR&D Fuels and Lubricants Department from its predecessor organization starting about 100 years ago to its demise during a reorganization in the late 1990s. It covers: Combustion research to improve engine efficiency and reduce emissions, Development of chemical, bench, engine, and vehicle tests to improve fuel and lubricant quality, Development of technology to reduce vehicle emissions, Research to understand and reduce air pollution, and Evaluation of alternative fuels and lubricants. In total, the above activities helped not only GM and the worldwide auto industry, but also society. They improved the operation of vehicles and the quality of the air in the United States and around the globe, favorably affecting the lives of hundreds of millions of people. They also created the recognition of and the reputation of the Fuels and Lubricants Department as the best of its kind in the world.

This paper has been written to further the designer's understanding of the military vehicle design parameters, as they exist today, of the modem day field army's need for a new family of vehicles, which will traverse all types of terrain rapidly and efficiently with an increasing variety of cargo an a weapons. The walking army of the past is yielding to the mechanized army on wheels. Since the design of automotive vehicles is at best a compromise, the effectiveness of the completed design depends largely on the talent and finesse of the designer. The GOER concept is such an approach.

The GOETZE bore distortion measurement system “Messfix”, or “Incometer, was brought into service in 1973. The advantages of this measurement system are described, with particular emphasis on the mathematical editing of the data — an essential prerequisite for determining different influence factors and implementing carefully targeted measures. Solutions for minimization of the bore distortion of open-deck and closed-deck engines based on years of experience are presented with the aid of examples. The characteristic distortion features of both engine designs and their causes are discussed. Finally, possibilities of evaluating the bore distortion of an engine by way of comparison or specific tests are outlined.

This paper will cover the significant technical advancements introduced to the Engine Alliance GP7200 turbofan engine that will power the new Airbus A380 commercial aircraft. The derivation of the engine from GE and Pratt & Whitney engine experience and the benefits of GP7200 engine architecture will be discussed.

The intensive search for an alternative low-emission powerplant for passenger cars has led to a re-evaluation of the gas turbine for this type of service. The GT-225 engine was designed as a research tool to aid in making such an evaluation. Factors which received special consideration in making design decisions included exhaust emissions, fuel economy and drivability. An extensive combustor development effort was undertaken to achieve low emissions. The engine has been installed in a test-bed vehicle to permit evaluation of emissions and other factors under actual driving conditions. Vehicle tests of the engine fitted with a low-emission combustor demonstrated the following emissions: 0.11 g/km (0.18 g/mile) HC; 1.2 g/km (2.0 g/mile) CO; and 0.23 g/km (0.38 g/mile) NOx.

The Model GTCP331 Auxiliary Power Unit (APU) is designed to meet the stringent demands of the next generation of commercial jet transports. The APU provides compressed air for cabin air conditioning, main engine starting, standby hydraulic power (via a turbopump) and in-flight anti-icing, as well as electrical power for both ground and flight operation. The GTCP331 will provide low cost of ownership, fuel efficiency and environmentally pleasing operation in the new Airbus A.300/A.310 and Boeing 767/757 aircraft. This paper presents information related to various aspects of the GTCP331 APU program. Specifically, data related to the configuration and power class selection, propulsion engine heritage design details, and development highlights are presented. The interrelationship of the APU to other aircraft systems and the role of the APU digital Controller in assuring efficient and safe operation are discussed.

Traditionally, ground vehicle aerodynamics has been researched with highly simplified models such as the Ahmed body and the SAE model. These models established and advanced the fundamental understanding of bluff body aerodynamics and have generated a large body of published data, however, their application to the development of passenger vehicles is limited by the highly idealized nature of their geometries. To date, limited data has been openly published on aerodynamic investigations of production vehicles, most likely due to the proprietary nature of production vehicle geometry. In 2012, Heft et al. introduced the realistic generic car model ‘DrivAer’ that better represents the flow physics associated with a typical production vehicle.

Corrosion is still the most frequent cause of deficiencies on cars over 5 years old. Life expectancy can be increased by approximately four years if double-sided galvanised sheet metal is used, if the vehicle is suitably designed to avoid corrosion and if currently available corrosion protection measures are carefully applied. The theories behind the corrosion protection properties of galvanised steel, i.e the barrier effect and cathodic protection are discussed in detail. The paper describes how this protective effect of the zinc coating is obtained in practice, and on which areas of the body and under what kinds of corrosive exposure it is effective. The results of this research have been implemented in the production of the Audi 100/Audi 5000 and the Audi 80. The paper describes the 100% galvanised bodyshells manufactured in volume production of these models, and outlines recycling possibilities.

A discussion is presented on the aerodynamic and mechanical design philosophy for the AiResearch model TSE36-1 240 shp gas turbine propulsion engine, which is currently being developed for the small two-to-three-place single engine helicopter market. The program objectives are to provide engines that have a low selling price and a low cost of ownership. The engine design is highly flexible and, thus, will be suitable for turboshaft and auxiliary power unit applications. This creates a large production base which, along with simplicity of design, will result in a low initial cost. Low cost of ownership will be possible due to a modular maintainability concept, high component reliability, and multifuel and oil operating capabilities. Experimental flight, development, performance, growth, and official FAA engine tests completed to date are also discussed.

In order to demonstrate the potential benefits of variable-turbine geometry in a turbofan engine, the U.S. Air Force Aero Propulsion Laboratory funded Garrett-AiResearch to build and test a variable-cycle turbofan engine. The engine selected for the demonstration is the Garrett-AiResearch Model TFE731-2 two-spool, geared-turbofan engine modified to accept variable geometry in the LP turbine, LP compressor, and exhaust nozzles. Throughout approximately 72 h of engine testing at sea level, static conditions, the variable-cycle engine has demonstrated that these variable-geometry components provide an effective means of rematching the engine components to obtain improved performance characteristics. For example, the concept of maintaining constant inlet total airflow and low-pressure-compressor surge margin while modulating engine thrust was demonstrated during this testing.

This paper makes the case for the gas generator engine - a type of compounded engines - as a potential future automotive engine. The existing gas generator engines are characterized by their mediocre performance and fuel economy. The case for the new gas generator engine is based on a proposed cycle principle, which achieves simultaneous improvements in thermal efficiency and power output/weight ratio. This very attractive engineering solution may transform the mediocre existing engines into new engines of exceptional promise, which merit serious consideration.

The lightweight gas turbine engine, which was originally a development of and for the aircraft industry, is finding increasing use in the propulsion of small marine craft. With the inception of this trend, problems peculiar to marine gas turbine applications soon became apparent. This paper deals with some of those problems and their solutions.

Although the gas turbine offers many advantages for long distance commercial vehicle applications, certain improvements must be made before it can successfully compete with the highly developed reciprocating piston engine. Both types of engines are compared on a thermodynamic basis to indicate their inherent characteristics and to show the extent to which various performance properties can be successfully matched to the gas turbine. One power unit, the split compressor differential gas turbine, is proposed as offering distinct benefits over the gas turbine types currently being developed. Its design features, operation, and performance in a continuing development program are described.

Stabilization is the process of improving undesirable characteristics or conditions of soils and aggregates to the degree where they can be used as a base or pavement structure in the construction of streets, highways, airports, dams, ect. , by the introduction of additives into the soil. With the scarcity and high cost of aggregate, the need for a mobile, in place, mixing machine developed. This led to the design of the RayGo Gator soil stabilizer. This paper will discuss the design features and application of this machine.

Extremely low noise levels at high power densities are achieved with a new inverted tooth silent chain system Two chains of random link design are phased such that the first order and subsequent odd orders of sprocket mesh frequency noise are canceled while remaining even orders are minimized by link randomization Current chain noise reduction practice has applied randomization with a primary emphasis on finer link pitch to control mesh frequency noise As the link pitch becomes finer, however, the chain loses strength and package size must increase to compensate The principle of operation of the new phased chain system is not primarily a function of the chain pitch Therefore, significantly higher power transmission densities can be achieved in the same package without sacrificing noise benefits To achieve the noise cancellation, motive power is transmitted by two chains mounted in such a manner that a specified phased lag exists between them at all times The noise reduction efforts described in this paper were achieved with a phase lag of 180° The new system is readily manufacturable It is made with current processing technology Its first production volume application is in the 1995 Chrysler Corporation LH vehicles

The 2.8 Liter 60° V-6 engine discussed here is an all new design made specifically for the 1980 Citation type of GM vehicle. This paper describes the technical features of the engine, and some of the development problems encountered and how they were solved. It also touches on the durability testing of the components and the total assembly. Paramount design goals for this engine were, from the outset, maximum reliability with minimum weight. Further, compactness of the total dressed engine assembly was dictated by size and configuration of the drive train compartment in the vehicle. Serviceability, tooling, and possible future displacement and material changes also were important factors. Extensive engine testing has demonstrated the desired reliability, as well as, very good power and specific fuel consumption. The overall weight, with the use of cast iron in both the cylinder heads and the block, fulfills the design goals.

A new 3.3 litre engine with 90° V-6 configuration was developed to maintain pace with lightweight car programs. Chevrolet optimized the new engine from the stand point of package size and weight efficiency. Also springing from the mandates for stringent fuel economy on the cars to be driven in the future, came the necessity for smaller, more efficient power plants. Conversion of existing facilities enabled the manufacturer to minimize the cost of the new engine program and allow manufacturing to keep pace with the trend toward smaller displacement engines. Excellent fuel economy and responsive performance are the results of the combined engine-vehicle package.