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An analytical technique presented in this paper provides the capability to predict the crush response of certain automotive structural components. This technique was coded from the finite difference formulation to solve the highly nonlinear equations of motion of the structural components when subjected to large deformation. It is operational for production usage. As a production program, it has extensive user convenience such as interactive computer graphics in model generation, model editing, and output display. For the purpose of demonstration, four problems solved by using this program will be reported in this paper.

Hybrid vehicles, i.e., those containing two or more sources of power, have the potential of increased fuel economy under certain types of driving conditions. Systems currently being investigated include combinations of heat engines, electric drives, fly-wheels, and accumulators. In order to obtain fuel economy improvements over conventional vehicles, efficient components are required as well as a good system design. Hybrid powerplants appear more promising for heavier vehicles.

The art and craft of tunnel boring discusses the evolution of mechanized tunnel construction from prehistoric to modern times. Specific technical achievements and notably innovative projects are described. The modern boring machine and the optional methods for overcoming varying ground conditions are presented. The conclusion provides a hint for future development trends.

Extensive tests have been carried out with European and Japanese cars to investigate the occurrence of vapour lock and related problems under hot-weather conditions. Different criteria, based on gasoline inspection properties, were evaluated for their ability to control hot-fuel handling performance. Considerable market experience has been accumulated with the flexible control, RVP (mbar) + 7E70, which is preferred by the authors to the vapour/liquid ratio type of control because it is far easier to use in routine refinery applications and control. However, the two types of control are equivalent in their ability to predict the performance of a wide range of gasolines, including those which may result from reductions in lead content. In their tolerance to gasoline volatility, the European and Japanese cars are very similar to the catalyst-equipped California models tested by the CRC in 1975.

The cold-weather driveability performance of some European cars deteriorated in the early 1970s as a result of attempts to improve fuel economy and reduce exhaust emissions. Consequently, a test procedure was developed for rating the driveability performance of European cars equipped with manual chokes and manual transmissions so that the effects of ambient temperature and fuel volatility could be assessed. This procedure and its development are described and the effects of fuel quality, ambient temperature and engine hardware on the performance of European cars are discussed.

The spark-Optimizer is a closed-loop type electronic control device that continuously corrects the ignition timing; in effect it re-tunes the engine some ten times every second. In contrast to the better known pre-programmed controls, the Optimizer is an adaptive type system, in which the output influences the input. By providing the correct spark timing all the time, the Optimizer reduces fuel consumption considerably. This paper describes the spark-Optimizer in its advanced version including recent improvements, like biasing. A comparison with other electronic spark control devices show its superiority in accuracy, flexibility, simplicity, and production costs. Samples of test results show considerable fuel savings with the Optimizer.

Proper choice of feedback control strategy is not the only consideration in the feedback fuel delivery systems. Open loop strategies and design of control electronics effect system performance. A basic description of the system and interactions with the electronic control will be presented.

Calibration gases are an essential element of pollution measurement. Their importance is emphasized because calibration errors are translated directly to the measured data. The concept of a calibration gas department responsible for filling the needs of all exhaust emission test facilities within an organization is a proven method for improving accuracy and precision, reducing test variability and assuring complaince with the law. Centralized handling of zero and span gases for multiple test sites within a facility is cost effective. In our case, installation costs were paid back in less than a year from the savings in product cost, cylinder rental and material handling.

The ambient conditions in the test facilities, the dynamometer characteristics, and the test drivers influence the formation of the components in vehicular exhaust gas emissions. To quantify the specific effects a standard test vehicle which is equipped with a mechanized driver and a measuring system is used as a calibrating instrument. Variations of the barometric pressure were found to influence the exhaust test results significantly. Systematic errors up to a factor of two may be caused by malfunctions of apparently well-adjusted dynos. Furthermore, the drivers can create large deviations without violating the tolerances of the driving schedule.

This paper reviews studies in Europe during the summer of 1977 to investigate the possibility of expanding gasoline supply through relaxation of existing Reid Vapor Pressure (RVP) volatility specifications. Performance parameters investigated included vehicle vapor lock and hot weather driveability under both controlled and consumer operation. Overall, it appears that some existing RVP specifications could be relaxed and still provide satisfactory consumer protection levels. This would permit more optimum utilization of available high volatility, high octane gasoline components and expand gasoline product yields while minimizing crude requirements.

A multi-cylinder four stroke cycle spark ignition engine equipped with an exhaust gas recirculation (EGR) system to reduce nitric oxide emission has been comprehensively simulated in a computer program including intake and exhaust manifolds. The program was tested against experiments performed on a standard production four cylinder four stroke engine equipped with a simple laboratory made EGR system. A nitric oxide emission reduction of about 50% was obtained at the peak NO condition. In spite of simplified assumptions the comparison between prediction and measurement of some major engine variables was good. The simulation program holds promise as a tool for engine development work. An appendix is added giving the outline of the calculation procedure.

Data acquired from extensive studies concerning the driving behavior in European cities were analyzed and compared to driving cycles used in exhaust emission testing. The US 72 cycle is found to be a good approximation, nevertheless it should be modified. Especially its total duration and its feasibility to weight the engine warm-up phase must be optimized. An improved driving cycle based on the US 72 cycle was developed which lasts 445 seconds. This cycle should be repeated once - using separate CVS sampling bags - so that the influence of the warm-up phase can be taken into account.

Well in excess of a trillion passenger miles are driven each year in the U.S. in vehicles employing conventional brake fluids based on glycols, glycol ethers, alcohols, polyglycols and other closely related components. The ways in which these components are assembled offer an extremely wide array of physical properties and performance characteristics in a vehicle's braking system. This paper discusses the range of physical properties and performance characteristics attainable in conventional brake fluid formulations. The laboratory data is supplemented with field testing data.

A general purpose model of the internal combustion engine with time as the continuous independent variable has been derived for digital computer simulation. A significant advantage rests in the graphic display of maximum and minimum values of component forces and torques, or any model variable, as a function of crank angle. The differential equations of motion that describe component positions, velocities and acceleration were combined to describe the dynamics of the entire engine. Gas forces, as well as static, viscous and velocity-dependent friction terms, have been included. The IBM Continuous System Modeling Program (CSMP) was used to describe the engine and solve the equations. The model is easily adaptible to many engine configurations.

When power output of automobile engine increases adverse effects resulting from increase of heat load on piston become serious. For a cooling countermeasure it is necessary to clarify the path along which heat is transfered and to be familiar with heat coming from the top surface of piston. In case of small pistons without a forced cooling system at the inside face of piston, most of the heat flows out of piston toward cylinder line through the sliding surface of piston ring and piston. Although it is well known that piston ring is very important as heat passage, details of a heat flow pattern still remain quite unknown. Some authors developed a few experimental studies, but we think it useful to realize a deep theoretical study of the problem. We think also very important to focalize thermal resistance of contact between ring surface and piston. The research results make evident that fluttering of piston way receives heat in a reciprocating way on rear and upper surface.

Nonpredictable responses to certain kinds of noise have been revealed as a result of past analyses of receiver noise responses. It seemed that certain types of noise were not susceptible of classification as either white Gaussian or impulsive, but rather that some intermediate classification was necessary. The development of an improved measurement technique of man-made noise sources was then undertaken. These techniques would then be applied in the measurement of noise radiated by several commonly found man-made sources. The measurement technique developed consists of displaying the noise power spectra in incremented bandwidths on a spectrum analyzer. Ten different sources were measured and the bandwidth factors recorded.

This paper discusses important considerations for performing meaningful electromagnetic radiated susceptibility tests of automotive electronic components. It is written primarily to aid new EMC engineers who are, or will be, involved in evaluating the susceptibility of electronic components and systems. The objectives are to minimize some of the pitfalls so common in performing measurements and to introduce new improved techniques that have been developed or have been proposed. Factors discussed include: 1) a review of some present susceptibility measurement technique problems; 2) swept versus discrete frequency testing; 3) test-field exposure time; 4) diagnostic testing; 5) implications of conducted versus radiated susceptibility testing; 6) relating testing results to operational “real world” environment; and 7) the need for complete vehicle testing. Recommended testing procedures are then proposed.

The properties of silicone-based brake fluids have been discussed in many recent papers and trade publications. Although the performance data are impressive, much of it is based on laboratory evaluation rather than on actual on-road use. The purpose of this paper is to respond to one of the basic tenets of the automotive engineer (Show Us The Hardware!). Included will be the results of well over two million miles of fleet testing which have demonstrated greatly improved performance and component life under a wide variety of adverse conditions.

A program to evaluate silicone brake fluids for use in military vehicles operating in various climatic conditions was begun in 1967. After 6 years of laboratory testing and numerous improvements in the characteristics of these fluids, a vehicle field test was initiated in the spring of 1973. Three candidate silicone fluids were selected and installed in M151 1/4-ton cargo vehicles, and M-715 1-1/4-ton vehicles operating at the Tropical Test Center (TTC), Panama Canal Zone, the Yuma Proving Ground (YPG), Arizona, and the Arctic Test Center (ATC), Fort Greeley, Alaska. Brake parts were inspected after 1 year of operation, and all parts were removed and inspected after 2 years of operation. After 2 years of service at TTC and YPG, the two water intolerant silicone fluids were significantly better than the water tolerant silicone fluid and the conventional VV-B-680 fluid.

A high-speed flat surface tire rolling resistance test facility has been developed to evaluate tire rolling resistance characteristics of a free-rolling tire and power transmission efficiency of a driven tire under controlled conditions. A continuous steel belt simulates the flat surface roadway. The tire contact patch is supported by means of a hydrostatic bearing. A new three-axis load cell has been developed to measure low fore/aft and lateral forces in the presence of a large vertical force. The load cell allows use of a live axle. In addition, discussions of the measurement instrumentation, the annunciator system, and the machine performance specifications are also presented.