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The purpose of this paper is to outline how a small Stirling Engine is utilized as a power source in a Total Energy System for recreational vehicles. The system provides electricity, heat and air-conditioning at a higher comfort level. The system also provides simplicity of operation.

The characteristics of large amplitude wave propagation in variable area ducts were investigated in order to gain a more thorough understanding of exhaust systems for power tuned two-stroke engines. An apparatus to simulate the power stroke of a two-stroke motorcycle engine was developed, using a stock Yamaha 360 MX barrel, cylinder head, piston and ring. In this way, a single pulse of pressurized air could be introduced into virtually any duct geometry. An ocilloscope trace of the subsequent exhaust pulse and duct interaction was photographed. The resulting pressure-time histories were used to experimentally evaluate the effects of several duct terminations on the shape and timing of the reflected wave. The investigation resulted in quantifying the effects of an orifice plate and converging cone termination and in determining the best termination for a Yamaha 360 MX engine.

Following an analysis of the state of the art,the typical values of emissions and fuel consumption of 2 and 4 stroke engined motorcycles, which comply with Federal Std. 1978 are examined. In view of a further reduction in emission levels, experimental results of an unconventional 2 stroke engine, with reduced losses of fuel mixture during scavenging are reported. Considerable fuel economy is obtained while the reduction in emissions, although less remarkable is not negligible: about 50% of unburned hydrocarbons and 75% of carbon monoxide as compared to a conventional 2 stroke engine of same performances. Fuel consumption, as resulting from tests, is competitive with 4 stroke engines at wide open throttle and quite better at partial loads. Finally, a different approach to emission regulations, based on a total index of pollution, is proposed.

The saving of over five billion gallons of gasoline yearly is a potential that cannot be ignored. What this should suggest to legislators, energy planners, transportation planners, urban planners, and economists is that they should encourage the use of the moped in the United States as an alternate form of short-haul transportation. Moreover, this should suggest that they encourage a change of the transportation scene in the United States toward a more compact, efficient, and economical mode of transportation: the moped.

Among the surface transportation noise control policies under consideration by governmental bodies are the methods of noise control, the magnitude of noise standards, and the priority each vehicle type will receive during the legislative and regulatory processes. A factor in the determination of these policies ought to be the relative contributions of each vehicle type to overall surface transportation noise. To help develop the substantial data base necessary for objective determinations, an investigation crew conducted two days of motor vehicle traffic sound level monitoring. The results indicate significant differences in noise levels and sound energies between motorcycles with stock exhaust systems and motorcycles with modified exhaust systems, and also between garbage trucks, other truck types, automobiles, and motorcycles.

The results of a survey of candidate power systems for small undersea vehicles are summarized. Power systems having capacity of 1 to 30 kW and endurance from 1 hour to 90 days are treated. Emphasis in this paper is given to electrical power systems. The performance of electrical power systems is compared in terms of overall weight and volume versus mission time with the performance of several candidate open cycle and closed cycle heat engines.

The establishment of high speed endurance records using production motorcycles is discussed. Modifications to increase specific engine output while maintaining reliability are described, and some observations on the experience of riding the motorcycle are offered.

An advanced gas turbine, the Detroit Diesel Allison model 570-K has been developed and is available for marine and industrial use. This engine is compact and lightweight with installation and maintenance features suited for economical life cycle costs. The engine is offered in two models that have each been performance matched for a particular use. The 570-KA is “marine matched” and the 570-KB is “high-power matched”. The paper describes how this matching is accomplished and the resulting advantages of this unique approach.

Management of Reliability Risk is essential to the success of new Product Programs. Reliability objectives should be clearly stated at the start, and progress toward this object evaluated at key decision (investment) points in the program. Reliability growth concepts are used to manage risk.

Some recent develpoments in wind and ocean power systems will be reviewed with emphasis on the Tornado-type Wind Energy System and the Dynamic Dam System. Basic requirements for an economically viable wind and ocean power system will be outlined. How the sytems to be discussed will be able to meet these requirements will be described in some details. It is hoped that in the not-so-distant future, the prospects for harnessing the immense amounts of wind and ocean energies will be fully realized for the mankind.

Truck engines currently reject up to 40% of the total fuel energy in the exhaust. Because of increasing petroleum costs there is growing interest in techniques that can utilize this waste heat to improve overall system efficiency. This paper examines and compares improvement in fuel economy for a broad spectrum of truck engines and waste heat utilization concepts. The engines considered are the Diesel, spark ignition, gas turbine, and Stirling. Principal emphasis is placed on the turbocharged four-stroke Diesel engine. Because of increased exhaust energy and a large potential improvement in performance, the still-to-be-developed “adiabatic” Diesel is also examined. The waste heat utilization concepts include preheating, regeneration, turbocharging, turbocompounding, and Rankine engine compounding. Predictions are based on fuel-air cycle analyses, computer simulation, and engine test data. All options are compared on the basis of maximum theoretical improvement.

The development of an automotive hydromechanical transmission is described and the results of in-vehicle testing presented. Fuel economy and performance results are encouraging; emissions increase, however. A second generation transmission is in the design stage; critical components are undergoing development and testing. Significant progress has been made in reduction of size, weight and level of noise generation.

Advanced research in the areas of vehicle safety and occupant protection in recent years have concentrated on developing systems and techniques that perform at impact speeds of 50 mph or greater. Recent developments on the NHTSA's Research Safety Vehicle program have indicated these efforts can be met with some measure of success. The question naturally arises then for the restraint systems as to what their performance would be in a more conventional vehicle. How well would restraint systems which were designed for an advanced crashworthy vehicle structure perform when integrated into a small production vehicle. To investigate these questions the NHTSA sponsored a program at Dynamic Science to integrate advanced restraint systems into a small production vehicle and to evaluate their performance over a variety of impact conditions. The vehicle selected for this program was the 1976 Volvo 244 and the restraint systems used were those developed for the Minicars RSV.

The Energy Policy and Conservation Act (EPCA) was enacted into law in December 1975 and is an important part of our national energy program. A section of the EPCA is concerned with “Improving Automotive Efficiency” and delegates various rulemaking responsibilities to the Department of Transportation relating to both passenger automobiles and nonpassenger automobiles. The scope of this paper is limited to a discussion of passenger automobile fuel economy standards for model years 1981 through 1984. A review of the background and rationale for the rulemaking is included.

The objective of this paper is to carefully examine the single most costly activity in reclamation--spoil leveling--and discuss technical details of leveling processes and new methods that have been developed to increase productivity and thereby reduce the cost of these leveling operations. This paper reviews technical data and presents conclusions resulting from the conduct of a series of hardware development and demonstration projects performed by the Southwest Research Institute for the U.S. Bureau of Mines and the U.S. Department of Energy.

More than 250 participants from 18 countries attended this meeting offering a total of 24 papers presented by speakers from 11 countries. The program of the colloquium provided an almost complete review of the present state of technology in the field of multigrade engine oils and their development. Besides the requirements of engines for specific engine oils and the fundamentals of rheology, the following main subjects were discussed: Viscosity classification of engine oils development in the USA and in Europe; Chemical and physical properties of viscosity index improvers; Cold flow behavior and high temperature viscosity of VI-improver containing oils; Influence of mechanical, thermal, and oxidative stresses; Engine performance of multigrade engine oils; Startability and pumpability of engine, oils. Some of the more important results and conclusions related to the subject of the relationship of engine oil viscosity to engine performance are reported and discussed.

Up to the present, the “W” portion of multigrade engine oils were classified only with regard to their low temperature startability by viscosity measurements at -18 C in the Cold Cranking Simulator. Because of the low shear rates encountered at the suction side of the oil pumps, the low temperature pumpability of the oils in the engine were not being considered. The investigations which were promoted by the DGMK were conducted to correlate the low-temperature pumpability of multigrade oils in a full-scale engine with suitable viscosity measurements and with results of tests in laboratory pumping rigs. Comparative measurements of viscosities were obtained with different viscometers. A critical shear rate of G = 50 s-1 was found for the borderline pumping conditions of the test engine. Good correlations were obtained between viscosity data of a rotational viscometer and engine pumping data.

When dealing with overall engine performance, engine journal bearings are recognized to be of major importance. Their lubrication can be critical, especially with increasing sump temperatures, as it is already a high energy consuming process. Of all the measurements possible to control engine bearing performance, temperature measurements are the most advantageous and simplify the recording process.

A simple rotary viscometer has been constructed in which multi-grade oils can be tested at temperatures up to 150°C and at shear rates of up to 4 × 105 s-1. Correlation has been made using this apparatus between multi-grade oil shear stability and engine bearing and cylinder bore wear. However, additional tests demonstrated that the chemical action of anti-wear additives also has a major influence on cylinder bore wear.

Four multigrade engine oils, containing the same base oil plus SE additive package but VI improvers of differing shear stability, were evaluated in 80 000 km of high-speed, high-temperature vehicle service. Bearing, piston ring and valve guide wear, as well as oil consumption, oil filter plugging and engine cleanliness were all worse for the engines operated on the low-shear stability oils. The wear differences were traced to differences in high-shear-rate viscosity, while the cleanliness, filter plugging and oil consumption differences occurred because of excessive wear or polymer shear degradation. These results suggest that engine oil viscosity should be specified under high-shear-rate conditions.