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A very straightforward procedure for solving ride quality problems is discussed. This procedure utilizes advanced dynamic testing and system modeling techniques in a logical three-step sequence. The first step is to define the nature of the problem through measurement of data during operation of the vehicle. The second step involves the measurement of vehicle dynamic characteristics such as resonant frequencies and mode shapes through controlled lab tests. This information is compared with the operating data to identify structural features which contribute to the ride problem. The last step is to assemble a dynamic computer model of the vehicle which can be used to quickly evaluate proposed solutions to the problem. Two examples are given which serve to demonstrate the effectiveness of this approach.

This paper presents the possibility of utilizing shock absorbers to decrease the aggresivity of a large car towards a small car at an impact of 40 mph. Reduction of such aggresivity would result in more damage to the large car, thereby reducing the impact on the small car. The conclusions demonstrate a definite decreased aggresivity of the larger car. Increase of the shock stroke does cause the large car to be crushed more in car-to-car collision. However, this occured at speeds below 25 mph, not the 40 mph as set by the study.

Many mini-computer applications are never implemented due to the shortage of skilled programmers. A high level programming language enabling non-programming personnel to do application programming is a possible solution to this problem. This paper covers G-M.'s experience in creating and implementing a problem-oriented language.

Two sources of data, one describing exposure and another describing fatal accidents, were used to estimate the national distribution of fatalities classified by four age groups and two vehicle size groups. The results show that the probability of receiving a fatal injury is greater in small cars than it is in large cars, and that the difference increases with age. This is true despite the fact that older drivers tend to be involved in less severe crashes. The reasons for these findings are discussed with particular attention given to injury patterns within different age groups.

With the use of a simulated exhaust system, the sulfuric acid and sulfur dioxide emission from a monolith noble-metal oxidation catalyst (Engelhard IIB) is measured. It was found that the storage rate of sulfur onto an initially sulfur-free catalyst decreases to a few percent of the sulfur rejection rate within 3-4 h. The amount of sulfur on the catalyst when the catalyst is in equilibrium with 20 ppm sulfur in the gas phase varies between 0.3 weight percent of the catalyst at about 400°C to 0.1 weight percent at 600°C. The sulfur can readily desorb from the catalyst if the gas phase sulfur content is lowered or if the catalyst temperature is increased. It was found that the conversion of sulfur dioxide to sulfuric acid reaches thermodynamic equilibrium at temperatures of 400-500°C and space velocities of 30,000 h-1. These conditions correspond approximately to a small V8 engine at 20 mph cruise.

Emission of SO3 or of sulfates can be virtually eliminated from catalytically controlled vehicles by operation in three way conversion mode as well as by operation of oxidation catalysts without air pumps. Hydrogen sulfide is not detected during normal excursions into the rich air-fuel region. Combined with the fact demonstrated by Volvo that vehicles equipped with Engelhard three way conversion catalysts meet or are lower than the 1975-76 California emission standards after 50,000 miles of driving, a viable solution exists for emission control of all pollutants including sulfates.

Noble metal oxidation catalysts have been shown to convert gasoline sulfur to automotive particulate sulfate emissions. A study was carried out in a laboratory bench scale reactor to evaluate the effect of vehicle operating conditions and catalyst type on the conversion of SO2 to SO3. The factors studied included catalyst temperature, exhaust gas O2 content and space velocity. The results are compared with data from a vehicular study designed to assess total sulfur emissions from catalyst-equipped cars. This study indicates that control of exhaust sulfate emissions may be achieved through close control of the oxygen content of exhaust gas and that the choice of catalyst affects the degree of conversion of SO2 to SO3 and the amount of oxidized sulfur retained in the catalyst system.

Because of space limitations and system complexity in many applications associated with gas turbine testing, extremely small flow measuring probes have sometimes been required. This paper presents several examples of these miniature probes-null type as well as fixed position-which have proved useful in aircraft and space power systems component testing and are applicable to automotive gas turbine testing. These probes are used to determine component or system performance from the measurement of gas temperature as well as total and static pressure, and flow direction. Detailed drawings of the sensors are presented along with experimental data covering the flow characteristics over the range of intended use.

Before the rise of “stagflation” as the catchword of the times, American industry was struggling with another: “Energy.” Ecology and environmental protection also achieved stardom with the populace, aided considerably by the media. But “materials resources” or lack thereof has not succeeded in gaining this kind of public attention. “So what if we have only a 30-day supply of chromium? Automobiles could do with less gaudy trim anyway,” seemed to be the general attitude. Industry, however, especially the metalworking industry, has become well aware of the materials problem this nation is facing and the fact that it is indeed a real problem. Industry is also painfully aware of the other problems-ecology, environmental protection, energy conservation, and so on-because it too often finds itself being blamed as the cause.

Over the past year or so there has been a short supply of materials for the ferrous castings industry. Raw materials and energy are important natural resources which must be conserved carefully and by cooperative efforts to insure that we have enough to supply our future needs. Materials serve functional needs of man, and man must therefore be conscious of the amount of material, energy, and labor necessary to produce a given product so that waste of materials and thus depletion of the sources for the manufacture of future products can be avoided. Recycling raw materials, resource diplomacy, and maintaining an adequate data base of information are important measures for energy and raw materials conservation. The real problem for the automotive industry and its need for ferrous castings is not only the inadequate supply of raw materials but the lack of sufficient foundry capacity to meet the demand for castings as a result of pollution control laws and low profitability.

The purpose of this paper is to discuss the availability of both resources and industry capacity for certain nonferrous metals that will be required by the automotive industry through 1980. Because of the complexity of the issues involved, it will be necessary to examine some of the basic problems that have been affecting resources availability and metal capacity, as well as those problems which are expected to be troublesome in the 1975-1980 period. Although the scope of the paper is supply availability, it will also be necessary to consider demand, particularly demand by the automotive industry, in the attempt to relate materials requirements to availability. Emphasis is placed on copper, zinc, and lead, with attempts at examining exploration; development; and capacity at mine, smelter, and refinery stages in an effort to pinpoint potential bottle-necks in supply flows.

A presentation on domestic steel production, both current and estimated for 1980. Focus is primarily on need for increased capacity and projections of availability of essential raw materials that may hinder or delay expansion. Included are outlooks for iron ore, zinc, nickel, ferro alloys, refractories, electrodes, fossil fuels, electric power and ferrous scrap.

Because of its outstanding fuel economy and its somewhat lower maintenance costs, the diesel engine has become dominant in the transportation field, especially for heavy-duty trucks. There is evidence that use of diesel engines in medium- and light-duty trucks as well as in passenger cars will increase in the future. Most diesel engines are installed in commercial vehicles. However if the engine is not carefully matched to the transmission and accessories, as well as to the specific vehicle application (severity of duty), the total package may be commercially unattractive. The purpose of this paper is to detail the most important considerations in matching diesel engines with transmission, components, etc., for use in commercial vehicles, specifically truck application.

The increase in power-to-weight ratio that results from the use of higher-horsepower diesel engines in highway service prompted this study of engine cooling. This paper covers the results obtained in testing different power-to-weight ratios on grades from sea level to over 11,000 ft and compares these results with those obtained from chassis and towing dynamometer cooling trials.

The object of this paper is to present an overview of the procedure leading to the selection of suspension system pivot points, show how to resolve terrain and maneuver loads at the tire contact patch to the vehicles' structure, illustrate the modeling technique used for stress analysis of suspension system components, and illustrate a few examples of suspension system models used to aid in the solution of ride and handling problems.

The comparative dynamic response (acceleration, velocity, and crush) of two cars, differing in mass and structural characteristics and impacting head-on, is examined for various closing speeds and payloads through the use of a computer simulation model. Among other results, this analysis of the so-called vehicle mix problem shows the inherent limitations of “equivalent barrier impact” concepts in analyzing such impacts.

Multiple cyl engine tests demonstrated that lean methanol operation gave improved tail pipe emissions and better Btu efficiency than gasoline. The reductions in NOx emissions were particularly significant. Some loss in maximum power output was experienced, but the loss was less than that for gasoline operation at equivalent NOx emissions. This program was directed toward making the minimum number of engine modifications to simplify retrofitting of existing vehicles to utilize methanol.

Current national interest in alternative fuels has placed considerable emphasis on alcohols, mainly methanol and its blends with gasoline. Vehicle studies with methanol-gasoline and ethanol-gasoline blends showed that adding alcohol to gasoline without carburetor modifications decreased carbon monoxide emissions, volume-based fuel economy, driveability, and performance. Depending on the carburetor's air-fuel ratio characteristics, hydrocarbon and nitrogen oxide emissions and road octane are either increased, decreased, or not affected. These effects can be explained on the basis of changes in stoichiometry, energy content, combustion temperatures, and detonation resistance caused by the addition of alcohol to gasoline.

Comparative testing of pure methanol, methanol/water blends and isooctane in single-cylinder engines has demonstrated that through proper utilization of methanol's fuel-lean combustion characteristics it may be possible to reach CO emissions of the order of 0.1 percent and NOx emission levels of less than 100 ppm in the raw (undiluted) exhaust. Exhaust treatment to remove unburned methanol and partial oxidation products might be required. Concomitant with decreased emissions are specific energy consumption improvements estimated to be in the range of 26 to 45 percent better than achievable with current gasolines and the associated low compression ratio engines and emission control systems. These energy consumption improvements are obtained by virtue of efficient lean operation and by utilizing the high octane values of methanol/water blends at high compression ratios.