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COMPARISON of work capacity per unit mass and volume of different energy carriers shows that liquid hydrocarbons are superior to other energy sources. Solar and nuclear powerplants as well as their use in conjunction with a steam engine are examined in this paper. Suitability of an electric drive is discussed. Using a production 2-stroke diesel engine and its development forecast, a comparison is made of spark ignition, diesel, and gas turbine engines. The status of the free-piston engine turbine combination is reviewed.

PEARLITIC malleable iron crankshafts are being used in the new Pontiac engine as a result of recent developments. This paper discusses the physical properties of pearlitic malleable iron such as elastic modulus, fatigue endurance, and tensile strength. According to the author, definite machining economies result from using pearlitic malleable iron crankshafts.

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.

In 1981, Ford Motor Company introduced a new family of fuel efficient four cylinder engines world wide. These engines, based on a compound valve arrangement in a hemispherical combustion chamber, were specifically designed for installation in light weight front-wheel-drive vehicles. Ford Research efforts were integrated with the resources of Ford U.S. and Ford of Europe to design and develop the engine in a compressed time frame. The technical and organizational efforts to accomplish this task, as well as, the design and development are discussed.

The present study investigates the wave propagation and attenuation in catalytic converters. The relationships for wave propagation in a catalytic monolith are derived first and then coupled to the wave propagation in tapered ducts. Analytical predictions are compared with experimental results to validate the theory.

Meeting the California Medium-Duty truck emissions standards presents a significant challenge to automotive engineers due to the combination of sustained high temperature exhaust conditions, high flow rates and relatively high engine out emissions. A successful catalyst for an exhaust treatment system must be resistant to high temperature deactivation, maintain cold start performance and display high three-way conversion efficiencies under most operating conditions. This paper describes a catalyst technology and precious metal loading study targeting a California Medium-Duty truck LEV (MDV2) application. At the same time a direction is presented for optimizing toward the Federal Tier 1 standard through reduction of precious metal use. The paper identifies catalytic formulations for a twin substrate, 1.23 L medium-coupled converter. Two are used per vehicle, mounted 45 cm downstream of each manifold on a 5.7 L V8 engine.

AS a basis for the analyses of this symposium, a hypothetical car has been used to evaluate the engine power distribution in performance. Effects of fuel,-engine accessories, and certain car accessories are evaluated. The role of the transmission in making engine power useful at normal car speeds is also discussed. Variables encountered in wind and rolling resistance determinations are reevaluated by improved test techniques. Net horsepower of the car in terms of acceleration, passing ability and grade capability are also summarized.

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.

A test cell was developed for evaluating a 6-speed automatic transmission. The target vehicle had an internal combustion 5.4L gasoline V8 engine. An electric dynamometer was used to closely simulate the engine characteristics. This included generating mean torque from the ECU engine map, with a transient capability of 10,000 rpm/second. Engine inertia was simulated with a transient capability of 20,000 rpm/second, and torque pulsation was simulated individually for each piston, with a transient capability of 50,000 rpm/second. Quantitative results are presented for the correlation between the engine driven and the dynamometer driven transmission performance over more than 60 test cycles. Concerns about using the virtual engine in validation testing are discussed, and related to the high frequency transient performance required from the electric dynamometer. Qualitative differences between the fueled engine and electric driven testing are presented.

The 2013 Ford Fusion will be launched with an optional automatic engine start-stop feature. To realize engine start-stop on a vehicle equipped with a conventional powertrain, there are two major challenges in the vehicle system controls. First, the propulsive torque delivery from a stopped engine has to be fast. The vehicle launch delay has to be minimized such that the corporate vehicle attributes can be met. Second, the fuel economy improvement offered by this technology has to justify the cost associated with it. In pursuing fuel economy, the driver's comfort and convenience should be minimally impacted. To tackle these challenges, a vehicle system control strategy has been developed to accurately interpret the driver's intent, monitor the vehicle subsystem's power demands, schedule engine automatic stop and re-start, and coordinate the fast and smooth torque delivery to the wheels.

Throttle tip-in/tip-out maneuvers generate a driveline torque transient which may produce an objectionable disturbance to vehicle occupants. Recent developments in vehicle design have contributed to increased severity in this response, which is known as clunk and shuffle. This paper describes experimental procedures which have been developed to quantify response levels and diagnose cases of concern. These techniques are useful for developing engine control systems which require transient strategies that differ greatly from those required for steady state operation. In addition, specific design and calibration modifications, which control clunk and shuffle, are described.

This paper explores the extent to which standard dilution tunnel measurements of motor vehicle exhaust particulate matter modify particle number and size. Steady state size distributions made directly at the tailpipe, using an ejector pump, are compared to dilution tunnel measurements for three configurations of transfer hose used to transport exhaust from the vehicle tailpipe to the dilution tunnel. For gasoline vehicles run at a steady 50 - 70 mph, ejector pump and dilution tunnel measurements give consistent results of particle size and number when using an uninsulated stainless steel transfer hose. Both methods show particles in the 10 - 100 nm range at tailpipe concentrations of the order of 104 particles/cm3.

The strain-life approach is now commonly used for fatigue life analysis and predictions in the ground vehicle industry. This approach requires the use of material properties obtained from strain-controlled uniaxial fatigue tests. These properties include fatigue strength coefficient (σf′), fatigue strength exponent (b), fatigue ductility coefficient (εf′), fatigue ductility exponent (c), cyclic strength coefficient (K′), and cyclic strain hardening exponent (n′). To obtain the aforementioned properties for the material, raw data from stable cyclic stress-strain loops are fitted in log-log scale. These data include total, elastic and plastic strain amplitudes, stress amplitude, and fatigue life. Values of the low cycle fatigue properties (σf′, b, εf′, c) determined from the raw data depend on the method of measurement and fitting. This paper examines the merits and influence of using different measurement and fitting methods on the obtained properties.

Intake and exhaust valve control has been combined with engine calibration control by an on-board computer to achieve a Variable Displacement Engine with improved BSFC during part throttle operation. The advent of the on-board computer, with its ability to provide integrated algorithms for the fast accurate flexible control of the entire powertrain, has allowed practical application of the valve disabler mechanism. The engine calibration basis and the displacement selection criteria are discussed, as are the fuel economy, emissions and behavior of a research vehicle on selected drive cycles ( Metro, Highway and Steady State ). Additionally, the impact upon vehicle driveability and other related subsystems ( e.g., transmission ) is addressed.

As vehicle tailpipe emission levels decrease with improvements in emission control technology and reformulation of gasolines, exhaust hydrocarbon levels begin to approach the levels in ambient air. Hydrocarbon speciation at these low levels requires high sensitivity capillary gas chromatography methods. In this study, a mixture of “synthetic” exhaust was prepared at two concentration levels (approximately 5 ppm C and 10 ppm C), and was analyzed by the widely-used Auto/Oil Air Quality Improvement Research Program (AQIRP) Phase II (gas chromatography) speciation method with a sensitivity of 0.005 ppm C for individual species. The mixture at each concentration level, along with a sample of ambient air, was analyzed a total of 20 times on 10 separate days over a 2½ week period. Concentrations of total hydrocarbons (HCs) and individual species (using the AQIRP library) were measured; averages and standard deviations were calculated.

THIS paper describes what the authors consider to be a simplified method of determining the vapor-locking tendencies of gasolines. The study of vapor lock was undertaken after they found the Reid vapor pressure method to be inadequate. The result of their work was the development of the General Motors vapor pressure, a single number which predicts vapor-locking tendency. The authors point out the following advantages of the new method: It allows direct comparisons of vapor-lock test results of different reference fuel systems; establishes distribution curves of volatility requirements of cars for vapor-lock free operation and of vapor-locking tendencies of gasolines; is a common reference value for both petroleum and automotive engineers. Finally, it more realistically evaluates the effects of small weathering losses on vapor-locking tendency than does Rvp.

Liquid fuels and the fuel vapors in equilibrium with them typically differ in composition. These differences impact automotive fuel systems in several ways. Large compositional differences between liquid and vapor phases affect the composition of species taken up within the evaporative emission control canister, since the canister typically operates far from saturation and doesn't reach equilibrium with the fuel tank. Here we discuss how these differences may be used to diagnose the mode of emission from a sealed container, e.g., a fuel tank. Liquid or vapor leaks lead to particular compositions (reported here) that depend on the fuel components but are independent of the container material. Permeation leads to emissions whose composition depends on the container material. If information on the relative permeation rates of the different fuel components is available, the results given here provide a tool to decide whether leakage or permeation is the dominant mode of emission.

A simple set of equations has been developed to characterize automotive fuel behavior in fuel tanks, fuel vapor systems and fuel rails, particularly under hot weather conditions. The system of equations links the vapor pressure P, the temperature T, and the mass fraction evaporated Z. Parameters are determined empirically from laboratory vapor pressure and distillation tests. With appropriate values for heat capacity, heat of vaporization, and vapor composition, the equations can be used to estimate upper flammability limits, fuel weathering under hot fuel handling conditions, pressure rise in tanks, and evaporative vapor generation. The equations were developed as part of a larger fuel vapor system model.

The development of systems and components for control of exterior noise has traditionally been done through an iterative process of on road testing. Frequently, road testing of vehicle modifications are delayed due to ambient environmental changes that prevent testing. Vehicle dynamometers used for powertrain development often had limited space preventing far field measurements. Recently, several European vehicle manufacturers constructed facilities that provided adequate space for simulation of the road test. This paper describes the first implementation of that technology in the U.S.. The facility is typical of those used world wide, but it is important to recognize some of the challenges to effective utilization of the technique to correlate this measurement to on road certification.

An experimental modal model of an early prototype car was constructed and validated against test results. The model was then used to suggest practical hardware modification alternatives which would: (1) shift the steering column resonant frequency away from the idle range, and (2) maintain a low steering column tip vibration within the 600-750 RPM idle range. This model was also used to evaluate the effectiveness of tuning radiator mounts to the overall vehicle idle quality. It was found that a pair of braces from either the steering column bracket to brake pedal bracket or to the cowl top area could improve idle shake of the test vehicle. The driver side brake pedal brace alone is not effective. However, the passenger side brake pedal brace alone is as effective as the two brake pedal braces together. It was found that the radiator mounts on the test vehicle are extremely non-linear. Therefore, tuning the mount to improve idle quality is impractical.