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Viewing 161941 to 161970 of 183943
1970-02-01
Technical Paper
700524
Johannes F. Schwar, Jeffrey A. Myers
This paper presents some of the technical considerations that underlie the development of the master plan and the establishment of design specifications for Ohio's Highway Research Laboratory. It describes the overall features of the master plan and discusses some of the critical design features as these relate to the various tracks and other field facilities. The development of the master plan was guided by a study of the layout of existing proving grounds and by the experience gained over the years in their operations. It was guided furthermore by a set of principles relating to operational considerations, considerations of flexibility in the layout, land utilization, safety, capacity, and cost. Finally, it was guided by an indication of future research and development needs as expressed by researchers and potential sponsors in both government and industry.
1970-02-01
Technical Paper
700523
William A. Gross
Tests conducted to evaluate performance and reliability characteristics of military vehicles are described. Conducted by the U.S. Army Test and Evaluation Command, the tests range from those to support research and design, through engineering tests to determine suitability of finished designs, to verification of production processes and quality assurance. The vehicle testing facilities of Aberdeen Proving Ground are presented in detail.
1970-02-01
Technical Paper
700525
E. J. Ash
Once a new engine is designed, it is subjected to extensive development programs prior to manufacture in production volumes. Many in-vehicle and engine dynamometer tests are required to integrate a reliable powerplant into a commercial vehicle. Development engines are limited in number and built of premium cost experimental parts. To prevent the failure of development engines, adequate strength of all structural components is necessary early in the development program. This paper examines how experimental stress analysis was used in assuring adequate strength of the new Chrysler 245 cu in. 6 cyl engine.
1970-02-01
Technical Paper
700521
Gilbert K. Brower
Diesel fuel specifications have undergone major revisions during the past decade. Actions taken to date do not satisfy the expressed requirements of the majority of diesel engine users and engine builders. Reference is made to the compatibility of current diesel fuel specifications with other middle distillate fuel specifications. Premium diesel fuels and fuel additivies are discussed. Constructive diesel fuel specification revisions are proposed which should satisfy the current needs of all diesel fuel consumers and diesel engine-builders and still be acceptable to the refiners and marketers of diesel and other related middle distillate fuels.
1970-02-01
Technical Paper
700517
R. M. Rusnak, W. M. Spurgeon, F. W. Aldrich
Brake linings and pads are among the most critical components in an automobile and therefore testing to determine their properties and performance is of great importance. The types of tests employed are described and the purpose of each is discussed. Functional testing is performed on either dynamometers or vehicles. Characteristics of the dynamometer and vehicle are discussed as well as the correlation between results obtained from each. The state-of-the-art in friction material testing is reviewed. Areas of possible future significant advancement exist in better correlation of vehicle and dynamometer results and development of a research dynamometer.
1970-02-01
Technical Paper
700515
Bohyun Yim, George R. Olsson, Peter G. Fielding, Glenn G. Balmer
The dynamic equations for an automobile in braking maneuvers are simplified in two steps. First, a nominal rectilinear trajectory is considered, with a constant deceleration rate. Secondly, a small perturbation in sideslip angle is examined, and the small disturbance equations of motion are derived. Solutions are obtained in terms of Bessel functions. The vehicle response is deemed stable when initial perturbations to the nominal trajectory are damped, and the perturbed motion is oscillatory. Algebraic expressions for the stability criteria are derived, illustrating the effects of speed, road frictions, tire slip-ratio, and vehicle design characteristics on vehicle response in braking maneuvers.
1970-02-01
Technical Paper
700513
R. R. Svenson
Truck air brake performance at low operating pressures is important to the owner because it represents the service range representative of the greatest amount of use. This paper presents the factors involved and the results to be expected from the most commonly used brakes on line haul trucks in current use. Included are representative input-output curves of the brakes. From a safety standpoint maximum performance at rated load is of paramount importance but service life is determined by balance at low operating pressures.
1970-02-01
Technical Paper
700516
George R. Olsson, Peter G. Fielding, Glenn G. Balmer
An evaluation of the applicability of braking control systems for highway vehicles was carried out. Elements of the study included development of a theory of vehicle response in braking maneuvers, design of logic for a braking control system, incorporation of the control in a hybrid computer simulation of a motor vehicle, and evaluation of control system performance. Benefits of braking control systems are illustrated in terms of improvement in stability characteristics (rear-wheel control) and in directional control (four-wheel system).
1970-02-01
Technical Paper
700514
James E. Nelson
An effort was made to evaluate accurately truck air brake performance balance at low application pressures by means of comparing drum temperatures. This procedure produced excellent results, and is a fast, practical method for evaluating brake performance of combination vehicles. The drum, hub, and wheel assemblies used in this evaluation were all the same type and weight. The s-cam used was a 16-1/2 X 7 in. and the wedge was 15 X 7 in. Mixed combinations of these types were tested. It was found that s-cam brakes are more effective when used on drive axles than when used on trailing axles. A tractor protection valve with a built-in pressure increase of 33% to the trailer brakes was installed to compensate for the more effective drive axle brakes and this provided the desired braking balance.
1970-02-01
Technical Paper
700511
R. E. Paggi, R. E. Andrus
A laboratory engine test technique has been developed to stress motor oils such that their relative high-temperature thickening characteristics in severe service can be predicted in a reliable manner. Engine mechanical condition, operating environment, and motor oil composition are important parameters affecting the thickening phenomenon. The mechanisms of oil thickening are complex and may involve nitrogen fixation or soap formation as well as bulk oxidation.
1970-02-01
Technical Paper
700512
Robert J. Morse
The role of air brake system pneumatic pressure and time differentials in total vehicle brake system performance is discussed. The magnitude of pressure differentials for typical air brake system valves is shown and the significance of both ascending and descending differential discussed. Transmission times for typical combination vehicles are shown and the effect of both pressure and time differentials at various axles on the proportioning of brake system work is developed. A number of means to deliberately unbalance pneumatic systems to compensate for unbalance in other components and thereby achieve better total brake system balance are discussed.
1970-02-01
Technical Paper
700509
W.C. Edmisten, J.V. Peterson, R.A. Sholts
Recent trends in engine design and automotive service have led to increased engine oil temperatures and, as a result, to occasional reports of excessive oil thickening in service. The thickened oils are usually very highly oxidized. Laboratory engine and bench tests have been developed to evaluate three parameters which affect oil thickening. The role of chemical inhibitors, base-oil volatility, and moderate temperature service were evaluated. Chemical inhibitors were effective in controlling excessive oxidation, but significant thickening may occur because of base oil volatilization. Prolonged service at moderate temperatures depleted the ability of an oil to resist excessive oxidation at high temperatures.
1970-02-01
Technical Paper
700510
L. J. Allman, A. E. Brehm, C. C. Colyer
Engine design and operational changes have led to increased motor oil temperatures. High oil temperatures have resulted in scattered instances of excessive motor oil viscosity increase in service. In the most severe oil thickening cases the oil would not flow, which caused engine failure. Trends in engine design including the incorporation of additional emission control devices, are expected to aggravate this potential problem further. A laboratory engine test technique has been developed which evaluates the performace of motor oils under high temperature operation. This technique was used to differentiate the various compositional parameters affecting oil oxidation and subsequent oil thickening. Insoluble oxidation products were responsible for most of the viscosity increase. The choice of blending stocks was significant to the stability. The influence of additives was minor.
1970-02-01
Technical Paper
700507
R. H. Kabel
A proposed test procedure, Sequence IIIC, has been developed to evaluate the thickening characteristics of engine oils. Results from the new 64 hr test procedure correlate well with the oxidative oil thickening observed in service vehicles and test cars. Sequence IIIC also evaluates the sludge and varnish tendencies as well as the wear protection provided by an engine oil. Sequence IIIC is intended to eventually replace the 58 hr Sequence IIIB test. Only minor changes in engine components and auxiliary equipment are required to convert a test installation from Sequences IIB-IIIB to Sequences IIB or IIIC.
1970-02-01
Technical Paper
700508
D. C. Bardy, P. A. Asseff
Information relative to oil thickening has been developed in road tests. Typical operating temperatures, as well as the length of time required to thicken oils in these tests, are described. A laboratory test procedure has been developed that shows a good degree of correlation with this field service. The effect of test conditions such as jacket temperature and piston ring design on oil thickening in the laboratory are described.
1970-02-01
Technical Paper
700502
R. W. Temple-Pediani
The ignition delay, combustion time, and smoke from a single drop of fuel on a hot surface were studied at various pressures up to 69 atm. The experimental results were correlated with previous data for drop evaporation on a hot surface, thereby yielding evidence that physical factors, in particular the rate of evaporation and consequent mixture formation, strongly influence the ignition delay and combustion of a drop. It is also shown that the magnitude of the critical temperature and pressure of a liquid fuel plays a significant role in all aspects of its combustion. A mechanism of ignition is proposed which contributes to better understanding of ignition delay phenomena.
1970-02-01
Technical Paper
700504
RICHARD W. HILDEBRANDT
The braking system presented in this article represents a new and forward thinking philosophy regarding commercial vehicle air brake systems. A concept that provides responsive service and emergency brake applications with optimum vehicle control, by the same driver action on the brake pedal. The uniqueness of the total system, and each circuit's function thereof, is explained in basic detail. In addition, the engineering, quality control, and assembly techniques to manufacture the vehicle with assurance that design intent is achieved, are discussed.
1970-02-01
Technical Paper
700501
Grunde T. Engh, Chung Chiang
A simulated I.C. engine intake system composed of intake port, intake valve, and cylinder was used to obtain intake port heat transfer information. The effect of air direction and valve lift on the heat transfer from the hot intake valve to intake air was determined. It was found that a higher rate of heat transfer occurred at the same rate of flow, for a smaller inclination angle. Decreased valve lift was also found to yield a higher rate of heat transfer for the same flow.
1970-02-01
Technical Paper
700499
Shin Matsuoka, Hidenori Tasaka, Yoshiro Nojiri
A low-pressure indicator incorporating high stability, high sensitivity to the required pressure, and nonsensitivity to engine vibration has been developed. This new indicator employs a peripherally fixed strain-generating disk and a wavy cone type of diaphragm, which is insulated from the outer body by a silicone O-ring. The generated strain was detected by a strain gage that had high compensating performance for the temperature. Analytical study was made to get the optimum design for disk thickness, diameter, and additional vibrating mass. The combination of this analytical study and the development of several new devices made possible the incorporation of various innovations in this newly developed low-pressure indicator which was designed to obtain data that would augment present methods of engine analysis.
1970-02-01
Technical Paper
700498
J. J. DiPonio
The manufacturing engineering profession, and it is a profession in the United States, is doing an excellent job of automating manufacturing processes so that more consumer goods can be produced at lower cost and better quality. The one area still untapped for major cost savings is the area of material usage. Chips represent waste, not only in material, but also in added disposal cost. They create a poor environment for our people to work in. More progress is being made today in the area of making chips larger and faster, and it is hoped that this paper will inspire the manufacturing engineers to ask the question, “Why make chips at all?” The processes that follow were viewed in production during an extensive trip to Moscow, Kiev, Dnepropetrovsk, and Konotop, in the Soviet Union.
1970-02-01
Technical Paper
700497
E. Cortina, H. L. Engel, W. K. Scott
The application of Bayes' Procedures to effect statistically optimum diagnostic decisions is described. The thesis is advanced that pattern recognition techniques can be used to reduce processing complexity and thus permit implementation of Bayes' Procedures in practical field portable equipment. This thesis is under evaluation in a test program in which journal bearing and wrist pin defects are detected from vibration measurements. Processing of vibration data by a computer programmed Pattern Recognition Technique resulted in design of “predetection” filters which can simplify the equipment required to detect the faults in real time.
1970-02-01
Technical Paper
700495
Henry G. Tobin
The wide interest in the development of diagnostic techniques for automotive purposes has led to developments in several areas. These include sensing methods, signal processing methods, and studies of how mechanical systems fail. This paper, concerned with only the first of these categories, presents an overview of sensors with emphasis on new developments that may be useful in the diagnostic field. Among the parameters which may be measured in automotive diagnostic systems are pressures, speeds, flow rates, temperatures, vibration, and electrical measurements. This paper will discuss various methods by which such parameters can be measured.
1970-02-01
Technical Paper
700496
John L. Frarey
Two basic approaches to pattern analysis as related to engine diagnostics may be recognized; a statistical-oriented approach that recognizes data patterns and relates them to known conditions previously observed; and a mechanically oriented approach that seeks through an understanding of symptom-fault relationships to predict data patterns. This paper deals with the prerequisites for employing the mechanical approach. Cases involving turbine engine gas path analysis, vibration analysis, and piston scuffing detection are examined with regard to these prerequisites.
1970-02-01
Technical Paper
700493
T. Asanuma, H. Yamakawa, H. Hayakawa
To analyze the behavior of fuel flow in a transient operation of a gasoline engine, the authors have developed a flowmeter based on a new hot-wire principle to measure the flow rate of pulsating fuel passing through a carburetor or an injection fuel tube. The device, which consists of twin wires mounted in a tandem arrangement, not only judges the direction of flow but also introduces no significant disturbance. Furthermore, this probe shows a response quick enough to permit measuring the pulsating fuel flow. This paper outlines the device along with a few applications.
1970-02-01
Technical Paper
700486
Lawrence C. Cessna
Mechanical property information is presented for the composite system, chopped glass fibers plus polypropylene matrix, where effective fiber-to-matrix adhesion has been achieved. The data presented were developed to serve three major purposes: to establish coupled glass reinforced polypropylene (coupled GRPP) as a material of a different class than conventional GRPP, to provide long-term data (creep and stress relaxation) for coupled GRPP which might form the basis for engineering design, and to illustrate the effects of such process-related factors as coupling, glass fiber concentration, fiber length, and fiber orientation on the structural properties of coupled GRPP systems.
1970-02-01
Technical Paper
700484
James H. Edgerton
The transport of increasing amounts of Army fissile and radioactive materials in the United States is presenting many technical problems because of the hazards associated with their movement. It is essential that criteria, guidance, and performance standards be established for transportation to facilitate safety during movement of these materials by all modes. The basic considerations in the transportation of fissile and radioactive materials are that they may present hazards to the health and safety of the transportation workers, passengers, people along the right-of-way, and the general public. Complying with all countries' regulations will provide for the control of these potential hazards by considering three basic factors: relative hazard potential of these items or materials, packaging performance standards, and the transportation environment expected.
1970-02-01
Technical Paper
700458
A. Marciante, P. Chiampo
A test method suitable for evaluating the lubricant oil influence on surface ignition has been developed. The effects on this phenomenon of oils without additives, oils with ashless additives, and oils with organometallic additives have been studied. In addition, the influence of additive introduction rate in the combustion chamber has been investigated and evaluated.
1970-02-01
Technical Paper
700629
J. Frederick Medford
If system safety analysis are to have a payoff in the design process, to assure they are not a waste, they must start in the early proposal cycle and become an integral part of the project planning and control cycle. This has been a real problem on major weapon system developments in recent years and has prevented proper implementation of the analysis effort. The heart of the system safety program effort is embodied in the system safety analysis types described in this paper. The problem is knowing when to use these analysis to minimize the cost of implementation and to get the greatest payoff. Knowing when to use these analyses judiciously comes with experience. Appendix A describes when each type safety analysis should be performed starting with the Concept Formulation Phase thru the Operational Phase of weapon system development.
1970-02-01
Technical Paper
700520
Robert S. Payne
The function of component parts of a typical truck evaporator are defined. These include evaporator coil, expansion valve, temperature control, blower, and air distribution system. The various heat inputs to the truck cab depend on engine cover temperature, type of insulation, air infiltration at various road speeds, number of cab occupants, etc. Outside air temperature is the greatest contributor to the heat which must be absorbed by the evaporator. In designing evaporators, space available in the cab must be considered so that the location of air discharge is most beneficial to occupants. The repair mechanic should be sufficiently trained to have a better understanding of the fundamentals of the system. With proper instructions to the truck operator and a scheduled preventive maintenance program, field repair problems should be alleviated.
1970-02-01
Technical Paper
700583
John B. Tenney, D. J. Withey
This paper describes test and checkout procedures for the Tektite ocean habitat system. The Tektite ocean habitat system is an underwater laboratory designed to support scientific and technical crews performing long term, shallow water diving experiments. In 1969, this system housed four aquanaut/scientists for a period of 60 days at a depth of 50 feet. The original experiment, sponsored by the Navy, verified the feasibility of the habitat as in-situ marine scientific laboratory and demonstrated its adequacy as a life support system. In April, 1970, the habitat began a program under the sponsorship of the Department of the Interior to support several five man teams, each performing two week scientific missions over a seven month time period. Testing and checkout of the habitat and its related systems, life support, power, communications, and water, involves activity both above and below the surface.

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