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Technical Paper

Alcoa - Massena Operations: An Integrated Aluminum Aerospace Forging Stock Producer

1991-09-01
912132
Alcoa - Massena Operations is a totally integrated aluminum producer from primary production to fabricated rod, wire and bar products. Alcoa - Massena Operations currently offers sixteen different alloys of forging stock; eight of these have a wide usage in a variety of aerospace applications. Alcoa - Massena Operations can offer both O (annealed) and F (as-fabricated) tempers in both Class I and Class II product forms. Class II forging stock offers two to ten times tighter tolerances from a diameter standpoint than those of Class I. Available alloys now include 2219 and 2618 designed for high-temperature use and 4032 alloy for high-temperature wear performance (e.g. aircraft pistons). Alloy 7475 is also available, it offers microstructural control to provide superior fracture toughness properties. Details concerning structure-property relationships and overall facility support to these products and their respective applications will be presented.
Technical Paper

Manual Control of Vehicles with Time-Varying Dynamics

1991-09-01
912078
An experiment was conducted to seek the models of the human pilot controlling a vehicle with time-varying dynamics manually. In the experiment the human pilot controlled basic first-order linear time-varying controlled elements in a compensatory closed-loop fashion for step and random inputs. The analysis of the experimental data has found that for the step input case the human pilot can be modeled as a stationary proportional-plus-integral controller, whereas for the random input case a stationary model with constant coefficients cannot describe the pilot's control behavior sufficiently well. A nonstationary time series analysis suggests that the human pilot's control behavior for the random input case is also time-varying; adapting his characteristics to the changing controlled element dynamics in such a manner that the error and output spectral characteristics do not make appreciable changes with respect to time.
Technical Paper

Gerotor Motors Incorporating Speed Sensing

1991-09-01
911780
Improved technology and Hall effect sensing as a source of electronic feedback in hydraulic motor systems are discussed. This paper is to introduce this technology and to heighten awareness. This technology will fill a need in monitoring and measuring methods for increased economy and will lend itself to ecological controls.
Technical Paper

Reducing Vibration of Reciprocating Engines with Crankshaft Pendulum Vibration Absorbers

1991-09-01
911876
Four-cylinder in-line automobile engines are inexpensive to build and economical to operate. However, they produce high crankshaft torsional vibration and high engine block vibration. Traditional ways to reduce this vibration may harm driveability and fuel economy, and may increase the cost of construction. Crankshaft-mounted pendulums have the potential to simultaneously reduce crankshaft torsional vibration and block shake at a reasonable cost without affecting driveability and fuel economy. Described in this paper is a study of the feasibility of applying pendulums to modern four-cylinder engines. The study involved the design, construction and testing of hardware, and an extensive analysis effort. Explored by analysis were optimal trajectories for pendulum motion, strategies for tuning sets of pendulums, the stability of pendulum motion and the shaking behavior of engines equipped with pendulums.
Technical Paper

Concurrent Engineering - Into The Curriculum

1991-09-01
912102
Abstract Changes in the world economic structure dictate that American industry must change or be relegated to a secondary role in the economic order. Academia must play an active role in the transition, despite an existing academic infrastructure that aggravates the ptolomeic view prevalent in industry today. Schools of engineering must incorporate team approaches and concurrent engineering concepts into the curriculum, the schools must reassess the design-product interface as presented in engineering classes.
Technical Paper

Flight Operations Safety Management

1991-09-01
912124
Managing operational flight safety is critical to the success of any air carrier operation. This paper describes one process for identifying, addressing and managing risk areas associated with air carrier flight operations. The five step process involves data collection, analysis, strategy design, implementation and critique. Several examples will be presented to illustrate the practicality and effectiveness of the process.
Technical Paper

Results and Lessons Learned from the STOL & Maneuver Demonstration Program

1991-09-01
912005
The STOL and Maneuver Technology Demonstrator (S/MTD) Program has validated a set of technologies that give a supersonic fighter all-weather Short Takeoff and Landing (STOL) performance while also enhancing up-and-away maneuverability. Significant reductions in both takeoff and landing distances, compared with the unmodified F-15, have been measured. The additional pitch control power of thrust vectoring has been demonstrated up to 30° angle of attack. The effectiveness of up-and-away reversing has been identified. First, major flight test results are presented and then lessons learned from this integration program are discussed.
Technical Paper

Modelling Linkages with Alternative C&E Simulation Methodologies

1991-09-01
911837
Alternative approaches for modelling linkages with several CAE simulation methodologies are discussed. The linkage design methodology is discussed in terms of the unique design features and capabilities that each CAE software package offers. The CAE software packages include: (1) ANSYS - a finite element analysis (FEA) program, (2) Integrated Mechanisms Program (IMP) - a multibody system analysis (MSA) program with its companion program, Geometric Modeling of Solids (GMOS) - a solid object geometric modelling program, (3) QUATTRO - a spreadsheet analysis program, and (4) special user-written analysis/animation programs. The linkage design methodology is discussed in terms of the unique design analysis features and capabilities that each CAE software simulation methodologies offers.
Technical Paper

Exploratory Testing and Analysis of Full Ceramic Ball Bearings

1991-09-01
911800
A small sample lot of Conrad type ball bearings fabricated of silicon nitride have been fatigue tested under full film liquid lubrication conditions. Analysis of the failed bearings points to a failure mechanism which is different than that of steel bearing fatigue. A failure model has been developed based on the static strength of the material, manufacturing process effects and basic contact mechanics. The failure mode found identifies one limitation of the use of ceramic bearings. The limitation is dictated by the tensile stresses produced in operation and the strength of the finished component. It was demonstrated that silicon nitride fails by mechanical fatigue when subject to high Hertzian contact stress. It must be clearly understood, however, that the high Hertzian contact stresses (above 350 k.s.i.) used in this test program are greater than those of recommended design practice. The bearing manufacturing, testing and failure analysis are discussed.
Technical Paper

Maglev Transit in America and US National Energy Strategy

1991-08-01
911627
This is an assessment of United States High Speed Guided Transit (HSGT) systems policy, vision, goals, and magnetic levitation development and commercialization technology; as affected by the new United States National Energy Strategy. It includes a brief review of the key aspects and assumptions which formed the basis for the US National Energy Strategy scenario, and the tactics proposed to implement a National Maglev transit network by the target year 2015 (1)1. It is followed by a historical review of past magnetic levitation vehicle developments, a review of the present status of Maglev trains, and an outline of future (EMA) Electro Magnetic Attraction levitation for speeds under 400 km/h; (SC) Super Conductive (EDR) Electro Dynamic Repulsion levitation for subsonic speeds approaching 900 km/h; and, an introduction to the (MPW) Magnetic Potential Well levitation effect as developed by Kozoriz (2) in 1976, also see (39).
Technical Paper

Gasoline Tolerant Methanol Fueled Ride Share Van

1991-08-01
911630
Abstract The decade of the nineties represents a unique time. Traffic congestion, petroleum shortages and health and environmental concerns resulting from fuel spills, smog and greenhouse effects are converging to force changes in the gasoline powered automobile. This presentation recognizes these circumstances as it presents the program and initial results from a flexible fueled ride-share van demonstration project. The ride-share vans are 1990 Plymouth Voyagers with two different powertrains: a 2.5 liter normally aspirated engine and a 2.2 liter turbo-charged engine. The 2.5 L fuel flexible engine has electronic spark and fuel management so that it can operate on any combination from 0 to 85% methanol (M85) and gasoline. The 2.2 L gasoline tolerant engine has electronic turbo-boost management as well as electronic spark and fuel control. The power boost increases with percentage of methanol and its associated octane enhancement.
Technical Paper

Reformulated Gasoline for California: EC-Premium Emission Control Gasoline and Beyond

1991-08-01
911628
EC-Premium is the second gasoline designed and commercially introduced by ARCO to reduce air pollution in Southern California. EC-Premium is designed to be used in cars using unleaded gasoline requiring the performance of a high octane gasoline. As with EC-1 Regular, the changes made to the gasoline include the addition of an oxygenate (MTBE), reduction in olefins content, reduction in aromatics content (and heavy aromatics in particular), reduction in benzene content, and reduction in volatility.
Technical Paper

Methanol Transit Bus: Research and Development to Operational Reality

1991-08-01
911632
The purpose of this paper is to document the development of the Southern California Rapid Transit District's (SCRTD) Methanol Demonstration Project and the integration of methanol buses into the existing diesel bus fleet. On June 12, 1989 the first three of thirty neat methanol powered transit buses entered revenue service in Los Angeles. In December 1990 the 30 bus demonstration project logged its one millionth mile. From an operational standpoint, particular emphasis has been placed on the development of methanol subsystem components and related equipment. In addition this paper will cover methanol fueling facilities, safety requirements, and the future development necessary to integrate this alternate fuel technology into everyday operations at the SCRTD. Additionally, the development of safety and training programs must parallel the development of the technology.
Technical Paper

Performance and Life Evaluation of Advanced Battery Technologies for Electric Vehicle Applications

1991-08-01
911634
Advanced battery technology evaluations are performed under simulated electric vehicle (EV) operating conditions at the Argonne Analysis & Diagnostic Laboratory (ADL). The ADL provides a common basis for both performance characterization and life evaluation with unbiased application of tests and analyses. This paper summarizes the performance characterizations and life evaluations conducted in 1990 on nine single cells and fifteen 3- to 360-cell modules that encompass six technologies (Na/S, Zn/Br, Ni/Fe, Ni/Cd, Ni-metal hydride, and lead-acid). These evaluations were performed for the Department of Energy and Electric Power Research Institute. The results provide battery users, developers, and program managers an interim measure of the progress being made in battery R&D programs, a comparison of battery technologies, and a source of basic data for modeling and continuing R&D.
Technical Paper

Design of Curved Solar Arrays for Solar-Powered Electric Vehicles

1991-08-01
911636
Abstract Students at Rose-Hulman Institute of Technology have designed, fabricated and efficiently integrated a flat solar array in Rose-Hulman's Solar Phantom solar-powered electric vehicle. The choice of a fixed, flat array was influenced by the simplicity and the cost of manufacturing and the number and cost of photovoltaic cells rather than just the energy collecting ability of the array itself. There are three basic types of solar arrays used for solar-powered electric vehicles: curved arrays, flat arrays, and tracking arrays. Our objective is to present a comparison of the three array types based on the power and size constraints imposed by the solar-powered electric vehicle race rules.
Technical Paper

A High Performance Zinc-Air Powered Electric Vehicle

1991-08-01
911633
Abstract Arizona Public Service (APS) has joined Southern California Edison (SCE) in sponsoring construction of a high performance Electric Vehicle based on a Honda CRX using DEMI's proprietary rechargeable Zinc-Air battery technology. The Zinc-Air CRX went 215 miles (346 km) on a single charge in its first test at an average speed of 45 mph (72 km/h) (SAE “D” cycle) and demonstrated a top speed of 87 mph (140 km/h). At the Inaugural Solar and Electric (S&E) 500 at the Phoenix International Raceway April 5-7, 1991, the CRX set a national record for a 1-mile closed course at 69.44 mph (112 km/h). The car won the pole position and dominated the 2 hour race winning by a comfortable 4-lap margin against a field of 12 other EVs from all over the United States. This paper covers the results of vehicle testing to date and the car's battery and electrical subsystems.
Technical Paper

Transportation Takes Advantage of Austempered Ductile Iron

1991-08-01
911638
The new family of austempered ductile iron materials, as recently specified by ASTM, is routinely able to outperform steel castings, forgings and fabrications in both structural and wear applications. Potential users are normally attracted by the lower price of austempered ductile iron generated by its inherent manufacturing cost advantages, particularly for parts which need high strength. However, a full range of outstanding features, including an 8-10% weight advantage and a high strength-to-weight ratio, make it of great interest to transportation engineers. These superior mechanical properties result from a truly unique microstructure that has already been proven in numerous transportation applications worldwide.
Technical Paper

Estimating a Process Control Model of Vehicle Front Wheel Alignment: A Case Study in Off-Line Experimentation

1991-08-01
911640
Abstract An off-line experiment was performed to estimate a model for on-line process control which describes the empirical relationship between the design and production factors affecting the front wheel camber angle. It is shown through a case study that models for process control estimated from off-line experiments may not generate on-line minimal variance predictions for vehicles representative of those produced in the assembly plant. This occurred in a case study experiment because a characteristic of the vehicle used in the experiment was identified which could not be manipulated or controlled during experimentation. It is shown that the developed methodology for augmenting the experiment would improve the model for on-line process control by generating minimal variance predictions for vehicles more representative of those produced in the assembly plant.
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