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The Chrysler “STEP” Test is used to simultaneously measure the thickness of the individual nickel layers in multilayer nickel deposits as well as the electrochemical potential difference between the nickel layers. This newly developed rapid test obviates the need for microscopic thickness measurements in many cases. More importantly, the electrochemical potential difference between nickel layers can be very easily measured. Since the potential difference is directly related to the corrosion resistance of the deposit, the efficacy of multilayer nickel deposits can be directly measured. Development of the test, typical results obtained on good as well as unsatisfactory deposits and implications with respect to improving corrosion resistance of plated parts are presented.

This statistical study of V-belt fatigue testing, with sample sizes of over 5,000, yields a valuable insight into V-belt reliability. With this basic information, the design engineer can have a firm base for establishing a relationship between laboratory and field testing, and drive design calculations. The data can then be related to projected reliability on the actual application. It will also serve as a reference base for establishing practical quality control standards.

A structural study of the cylinder block was made using a 4-cylinder, 1,800 cc gasoline engine with an aim toward reducing engine noise. First, we studied the relationship between cylinder block vibration and radiated noise, and also the principal component modes of noise and vibration. From the results obtained, it became clear that engine noise could be reduced by suppressing the basic natural vibration of the cylinder block. Then, alternative shapes of engine blocks were examined in an attempt to reduce noise with a minimal change in present production facilities and engine weight, using the finite element method. The trial cylinder block was built into an engine after examination by the impulse excitation method and holography. As the result of testing it in running condition, we were able to reduce the noise of the engine proper 2.5db-A with a weight increase of about 3 percent.

The USS CAROSEL* one-side-electrogalvanizing process is briefly described, and the properties of the product (USS GALVA-ONE)* are presented. Included is information on available grades, corrosion resistance, formability, coating adhesion, weldability, and paintability.

An experimental program was conducted at the U.S. Department of Energy’s Bartlesville (Okla.) Energy Technology Center to evaluate the effects of synthetic and special additive engine and differential gear lubricants on automotive fuel economy over the temperature range encountered in the United States. Using a climate-controlled chassis dynamometer facility on two 1978 vehicles, four engine lubricants were evaluated in the 1978 Federal test procedure and in steady-state operation from cold start at 20°, 70°, and 100° F ambients. In addition, three differential gear lubricants were evaluated in steady-state operation from cold start at 20°, 70°, and 100° F ambients using one 1978 vehicle equipped with torque and revolutions per minute measuring devices, which enabled the calculation of horsepower losses in the differential and the efficiency of the rear axle in addition to fuel economy.

The fuel-saving capabilities of various experimental and commercial passenger car engine oils have been demonstrated in extensive studies. Lower viscosity oils and those containing friction-reducing additives have shown measurable fuel economy benefits in a wide range of laboratory and vehicle tests. Several test techniques are described for screening fuel-saving engine oils and components. Closely controlled chassis rolls and over-the-road vehicle tests are utilized to demonstrate the actual lubricant-related fuel economy benefits. Within the range of variables included in this study, reducing engine oil viscosity is the most effective way to improve fuel economy. Fuel savings realized from friction-reducing additives are relatively modest and many of the more effective materials are shown to have poor performance in standard sequence tests, particularly regarding engine wear.

The future growth in power density in diesel engines is greatly dependent upon successful design of the bearings. The traditional analytical methods cannot account for or grossly approximate many of the important features of an actual bearing operation. A new computer program has been developed which uses the finite element method for a more accurate analysis of bearing performance under actual conditions. The program can analyze the type and location of oil supply grooves, taper, misalignment, noncircularity of journals and bearings, and various crankshaft machining defects. The paper provides a broad overview of the computer program and sample results for a variety of practical bearing features.

The automobile plays a very important role in the American way of life. The private passenger car has been for generations an expression of a basic American freedom called mobility. In our generation society as a whole, through the federal government, has imposed constraints on the expression of this mobility freedom. These constraints have been imposed in the form of regulations concerning safety, environment and energy. Accordingly, the modern automobile must then be designed to achieve competing objectives in the presence of severe constraints. Discussed here are modern optimization methods which can be useful in this design environment. Included in the discussion are the very powerful Generalized Reduced Gradient and Method of Multipliers algorithms. Mechanical component and system design examples are given which demonstrate the utility of the optimization approach. Particular attention is given to the engine as a major automotive component.

The boundary integral equation (BIE) method has emerged as a promising alternative to the finite element method because in many cases it may significantly reduce the generation and checkout time required to describe the geometry model. Structural analysis is simplified because only the surface of the component being analyzed needs to be defined. Advantages and limitations of the BIE method are discussed. Two example problems are modeled using both the finite element method and the BIE method. One problem is a planar analysis of a gear segment. The other is a three-dimensional analysis of a diesel engine piston.

More plastics than ever before, including thermosetting and thermoplastic, are being utilized for exterior body automotive applications requiring Class A finishes. The subject of meeting Class A finishes is becoming more important as materials such as SMC, BMC, and RIM are more widely used. The scope of the material presented is to discuss some basic requirements necessary to obtain a Class A finish and solutions to common production problems encountered on the finishing line.

After a review on history, market, physical facts of fuel injection follows a short description of present systems. Influences on fuel consumption and emissions, including Lambda-control, are described. Some notes are given on the influence of injection timing, single point injection, combination of fuel injection and ignition to a digital motor electronics. New development trends for less expensive and more effective systems are shown.

The role of NiO in three way catalyst systems is explored with respect to transient oxygen storage and water gas shift activity observed in lean-rich-lean exhaust composition changes. Oxygen storage behavior is observed to playa role in fresh catalyst systems but disappears on aging. However, storage phenomena are still observed in the presence of water and can be explained in terms of water gas shift activity. Nickel containing catalysts in which the nickel is highly dispersed readily form a surface nickel aluminate complex which minimizes oxygen storage and water gas shift capability. A proprietary catalyst which contains stable nickel oxide is capable of maintaining higher activity under transient operation after hydrothermal aging.

Monolithic three-way conversion (TWC) catalysts, at different precious metal concentrations, were aged on an engine dynamometer with fuel doped with lead (0.012 g Pb/gal). These catalysts were subsequently evaluated on an engine dynamometer to examine the effects of air/fuel ratio set point, temperature, and air/fuel ratio amplitude and frequency on the conversion efficiencies for NOx CO and HC. In all evaluations, as the precious metal concentration increased from 5 g/ft3 to 40 g/ft3, the NOx CO and HC conversions increased. Also, the smallest effect of precious metal loading on catalyst efficiency was found at the smallest air/fuel amplitude (±0.3 A/F). The highest overall conversions of NOx CO and HC were obtained at the stoichiometric control point for perturbations of ±0.3 A/F amplitude. Therefore, it appears that a considerable savings in precious metals can be realized if the A/F amplitude of a closed-loop feed-back control system is small (±0.3 A/F).

Comprehensive single-cylinder engine data for three combustion chambers were analyzed statistically in order to quantify the effects of engine operating conditions and chamber geometric variables on combustion characteristics, and of combustion on engine performance stability. Operating condition variables of interest were air-fuel ratio, residual fraction (internal plus external EGR), spark timing, engine speed, and fueling level (trapped fuel per cycle). Geometric parameters of importance were chamber “openness” and squish. Combustion and engine performance stability were found to be related such that engine stability was improved when combustion variations were reduced, as would be expected, and/or when the combustion event was shortened. The combustion, in turn, was affected by both the engine operating conditions and chamber geometric characteristics.

Experimental observations are presented of instantaneous local heat flux at one position on the cylinder head of a motored reciprocating engine. A range of compression ratio, speed, and inlet conditions were covered. The observations clearly show the phase shift between heat flux and driving temperature difference caused by boundary layer work effects. Correlation is briefly discussed.

Alternatives to cadmium plating on fasteners are investigated from the point of view of cost, corrosion resistance, torque/tension relationships and vibration resistance. Conclusions show that these are inter-related and point to the direction to be taken dependant on the criteria of the fastened joint under consideration.

This paper addresses an ongoing research program that describes and provides guidance on the effectiveness, costs, advantages and disadvantages of simulation training for Air Force flying personnel. In the current climate of drastically reduced fuel availability, alternatives must be available to train aircrew members operational mission essential skills. Air Force use of simulation has increased over the past few years. Such a trend is expected to accelerate in the future. In the past, the majority of R&D funding has gone towards development and improvements in simulation engineering technology. Consequently, there have been numerous improvements, however, less attention has been directed towards the ways these improvements could be used by operational training personnel. As a result, the current data base is insufficient to allow making tradeoff decisions concerning training methods, effectiveness and costs. Such issues are addressed by this study and are reported here.

This paper discusses the advances in mechanical fastening made over the last decade. More detailed analyses of the bolted joint have led to a better understanding of the relationships between the working loads imposed on the bolted joint and the stresses felt by the bolt. The induced preload (tension) in the fastener is shown to be the critical factor involved in the static and dynamic reliability of the bolted assembly. The need for more accurate assembly methods to insure good control of fastener tension has resulted in the development of special electronic controls which are being used on the assembly line. Preload loss mechanisms which occur in service were studied, and new fastener locking methods are being evaluated by means of transverse vibration tests. The designer facing the challenge of greater reliability and fuel efficiency has the recently developed fastening technology at his disposal.

A mathematical model is developed to represent an oxidizing catalytic converter in the exhaust system of a spark ignition engine in which the flow is non steady. By using the basic mass transfer, heat transfer and chemical reaction rate equations on the path lines the heat generated at the catalyst surface and the friction factor are allowed for in the generalized non steady flow relations using the method of characteristics. The model is included in a multi-cylinder engine simulation program. Secondary air injection into the exhaust system is represented by a simple mixing process without chemical reaction. A series of tests were carried out on a four cylinder two litre engine with a carbon monoxide and hydrocarbon oxidizing converter and secondary air injection. Comparison of results between experiments and computer calculations shows excellent agreement when the converter is new, but that if the catalyst surface is poisoned or aged the hydrocarbon prediction deteriorates.

This paper reviews piston and ring friction which can account for 65% of the mechanical friction in an internal combustion engine. It shows that cylinder liner lubrication is predominantly hydrodynamic with localized contact between ring and liner at TDC firing. The degree of contact may increase during transient conditions. Piston ring friction in the hydrodynamic region is proportional to the square root of the viscosity. The viscosity is affected by temperature and pressure which can reach peak values of 340°F and 4000 psi, respectively. Gains in fuel economy through viscosity reductions have been reduced in the last 25 years due to changes in piston and ring design.