Engineering Commons^™

Prediction And Control Of Asymmetric Vortical Flows Around Slender Bodies Using Navier-Stokes Equations, Tin-Chee Wong

Mechanical & Aerospace Engineering Theses & Dissertations

Steady and unsteady vortex-dominated flows around slender bodies at high angles of attack are solved using the unsteady, compressible Navier-Stokes equations. An implicit upwind, finite-volume scheme is used for the numerical computations.

For supersonic flows past pointed bodies, the locally-conical flow assumption has been used. Asymmetric flows past five-degree semiapex cones using the thin-layer Navier-Stokes equations at different angles of attack, freestream Mach numbers, Reynolds numbers, grid fineness, computational domain size, sources of disturbances and cross-section shapes have been studied. The onset of flow asymmetry occurs when the relative incidence of pointed forebodies exceeds certain critical values. At these critical …

Transient Heat Transfer Measurements On A Film Cooled Flat Plate In A Shock Tube, Rakhman Gul

Theses and Dissertations

During this study a simple model of a flat plate was chosen to determine heat flux from a high speed flow behind a shock wave into the film cooled flat plate. An electrical analog was used to convert the output of the heat flux gages into heat flux. Free stream turbulence within the flow behind the shock wave and that generated by a turbulence generator was determined and its effects on the heat transfer data were then studied for comparison with previous experimental work. The thin-film heat flux gages were calibrated and their calibration constants were then used to determine …

The Evolution Of The Wpi Advanced Space Design Program - An Evolving Program Of Technical And Social Analysis Using The Nasa Space Shuttle For Engineering Education, Fred J. Looft, Robert C. Labonte, William W. Durgin

Office of the Provost Scholarship

In December of 1982, Worcester Polytechnic Institute, with the cooperation and support of the MITRE Corporation, initiated a primarily undergraduate educational program to develop experiments to be flown onboard a NASA Space Shuttle. Christened the MITRE WPI Space Shuttle Program, it sponsored the development of five educationally meritorious experiments over a period of four years. Although the experiments were ready to fly in early 1986, the Challenger disaster delayed their flight until the Spring of 1991. The delay notwithstanding, the benefits of the first program were sufficient to justify the development of a second set of experiments. More comprehensive in …

On Local Stresses And Spring Constants Of A Sphere-Nozzle Connection, Ban-Li Lyow

Dissertations

This dissertation studies the local stresses and spring constants of a spherical shell with a nozzle attachment when it is under various loadings, namely radial force, overturning moment, horizontal shear force, and torsional moment. Because of the mathematical difficulty in modeling the nozzle-sphere configuration, particularly with nozzle opening, the finite element method (ANSYS package) is utilized in this study. The model used in this study is a quadrilateral thin shell element model when the γ_s (spherical radius/thickness) value is larger than 10. Otherwise the isoparametric solid element is used. The resulting stresses are basically biaxial state of stresses. It …

Development Of Techniques Of Artificial Intelligence In Identifying The Different Machined Surfaces, Yi-Ching Chou

Theses

This thesis deals with the identification of different machined surfaces with artificial inteligence techniques. There are five kinds of machining operations: grinding, turning, milling, EDM and waterjet which determine the characteristics of resulting surfaces. Topology of various specimens is measured using the surfanylizer. Twenty one parameters are extracted from the measurements to describe the characteristics. In this thesis, we develop neural and expert systems that recoginize and classify surfaces according to the machining methods.

Information Handling System With A Personal Computer To Assist In The Manufacturing Of Plastic Parts, Yi Chung

Theses

The ongoing personal computer development has led to its increasing application in manufacturing to improve productivity. Being more aware of this technology, most of these benefits have accrued to large firms. The intent of this thesis is to show that it is equally advantageous for small manufacturing companies to utilize them and show how they can do so.

The field of production control systems is discussed and those areas where personal computers can be applied are emphasized. Forecasting, warehouse management, material requirement planning, and inventory control are the most appropriate. An application example using dBase III plus to write the …

Some Aspects Of Integration Of Classification, Computer Aided Design, Process Planning, And Scheduling Of Flexible Manufacturing Systems, Suresh Godavari

Theses

This work deals with the role, problems and solution technique for integration of Computer Assisted Design, Classification, Process Planning, and Scheduling for a Flexible Manufacturing System. A lark spectrum of rotational and prismatic parts are considered.

A Knowledge-based rough classification and coding system [C&C] has been developed for coding similar parts using a Group Technology [GT] technique. In this module VP-EXPERT and DBase III Plus are used as expert system and database respectively. This module interfaces with a database for the retrieval and selection process.

The code obtained from the C&C system is the basis for the succeeding phases. The …

Deposition Of Particles In A Channel With Gravity And Image Forces, Jing-Shiun Lai

Theses

Deposition of particles in a parallel-plate channel under the influence of inertia, fluid viscosity, gravity and image forces was studied using trajectory method.

A laminar fluid flow of uniform and parabolic (or fully-developed) velocity profiles is assumed and the fluid is suspended with particles having the same velocity as the fluid at the inlet plane. The particles flowing into a horizontal parallel-plate channel have no initial velocity in the vertical direction. The influence of gravity force and image force produces a vertical motion which results in deposition of particles on the channel walls.

A trajectory method was employed to find …

Experimental Study Of The Internal Loads In A Cardan Joint, Johannes K. Waal De

Theses

A recent investigation by Fischer and Freudenstein questioned the validity of the negligible axial forces assumption in the static force analysis of Cardan Joints. The purpose of this paper is to experimentally assess this assumption for the dynamic case.

To this end an experiment was constructed to determine the axial forces acting on the intermediate revolute joints of a Cardan joint. A four-square test arrangement was prepared such that shaft intersection angle, shaft torque, and shaft speed could be varied. Strain gages were applied to the "arms" of the joint to measure the resulting strains due to the forces along …

Impacts Of Duct Leakage On Infiltration Rates, Space Conditioning Energy Use, And Peak Electrical Demand In Florida Homes, Florida Solar Energy Center, James Cummings

FSEC Energy Research Center®

Testing for duct leakage was done in 91 homes. Tracer gas tests found that infiltration rates were four times greater when the air handler was operating than when it was off. Return leaks were found to average 10.0% of air handler total flow. House airtightness, in 63 of these homes, determined by blower door testing, averaged 12.38 air changes per hour at 50 Pascals (ACH50). When the duct registers were sealed, ACH50 decreased to 10.93, indicating that 11.7% of the house leaks were in the duct system.

Duct repairs were made on 25 homes. Blower door tests found 12.30 air …

Test 1642: Ford 3230 (8x2) Diesel 8-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF THE TEST PROCEDURE General Tractors are tested at the University of Nebraska according to the Agricultural Tractor Test Code approved by the American Society of Agricultural Engineers and the Society of Automotive Engineers or official Nebraska test procedure. The manufacturer selects the tractor to be tested and certifies that it is a stock model. Each tractor is equipped with the common power consuming accessories such as power steering, power lift pump, generator, etc., if available. Power consuming accessories may be disconnected only when the means for disconnecting can be reached from the operating station. An official representative of …

Testing The Economic Order Quantity Model On Maintenance Inventory, Teresa J. K. Hall

Graduate Student Work

This pilot study seeks to determine the effect a non-traditional method of inventory control may have on industrial maintenance repair parts inventory. The application of mathematical models designed for production inventory to Maintenance, Repair and Operating (MRO) inventory has not been widely researched, although theorists and practitioners feel there is potential for some models. The Economic Order Quantity (EOQ) theory has proven to be effective in production inventory circles. This pilot study examined the effectiveness of the EOQ in terms of holding cost of the inventory and number of out-of-stock conditions versus the Weighted Moving Average method currently in use …

Osha Compliance By Small And Medium Business, Bill W. Trammell

Graduate Student Work

It is hypothesized that even though governmental rules, regulations, and policies along with ethical. social, and moral dictates within our communities now require, even demand, that businesses and industry provide their employees a healthful and safe working environment the opposite is often the case. There is a substantial number of employers, within the small to medium sized industrial manufacturers, whose chief executive officers: (1) fail to implement a safety program within their organization; (2) fail to provide more than token attention to employee safety and the intent of the OSHA regulations; (3) have no sincerity or intention to complying with …

Automating Tolerance Synthesis: A Framework And Tools, Stephen C.-Y. Lu, Robert G. Wilhelm

Department of Mechanical and Materials Engineering: Faculty Publications

This paper describes CASCADE-T—a new approach to tolerance synthesis that uses a complete representation of the conditional tolerance relations that exist between features of a part under design. Conditional tolerances are automatically determined from functional requirements and shape information. Tolerance primitives based on the virtual boundary requirements approach to tolerance representation are composed to form more complex tolerance relationships. Artificial intelligence techniques, including a constraint network, frame-based system, and dependency tracking are used to support flexible and detailed computation for tolerance analysis and synthesis.

Drainage Of Sandplain Seeps For Salinity Control And Stock Water Supplies, Richard George, Peter Frantom

Journal of the Department of Agriculture, Western Australia, Series 4

Sandplain seeps are derived from a shallow groundwater system which flows from the deep sandplain soils upslope. Seeps result in small areas of salinity and waterlogging, which can be the focus of soil erosion. Sandplain seeps may represent as much as 10 per cent of Western Australia's salt problem in the drier agricultural area. Several drainage experiments conducted between 1986 and 1989 determined the best methods of reclaiming sandplain seeps.

This article discusses the results of these drainage experiments. It comments on the most suitable method for reclaiming sandplain seeps and developing them for stock water supplies.

Whole-Farm Planning : Success At Wilgi Creek, Kevin Shanhun

Journal of the Department of Agriculture, Western Australia, Series 4

Ian and Bev Lynch own Wilgi Creek, a 376 ha mixed farming property at West Mount Barker in the 700 mm rainfall zone. In 1983, they started a whole-farm plan to overcome the problems of declining production caused by waterlogging (their biggest problem), salinity and deterioration of the remnant native vegetation. Today, their property is an example of a successful, wholefarm land conservation plan based on agroforestry, timber production, water harvesting and improved pastures.

Knowledge-Based Support For Management Of Concurrent, Multidisciplinary Design, Raymond E. Levitt, Yan Jin, Clive L. Dym

All HMC Faculty Publications and Research

Artificial intelligence (AI) applications to design have tended to focus on modeling and automating aspects of single discipline design tasks. Relatively little attention has thus far been devoted to representing the kinds of design 'metaknowledge' needed to manage the important interface issues that arise in concurrent design, that is, multidisciplinary design decision-making. This paper provides a view of the process and management of concurrent design and evaluates the potential of two AI approaches—blackboard architectures and co-operative distributed problem-solving (CDPS)—to model and support the concurrent design of complex artifacts. A discussion of the process of multidisciplinary design highlights elements of both …

Decoupled Dynamics For Control And Estimation, S. N. Balakrishnan

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Decoupling of the dynamical equations in polar coordinates is used to develop a control scheme for use in target-intercept problems with passive measurements. By defining a pseudo control variable in the radial coordinate, the radial dynamics is made independent of the transverse dynamics. After solving for the radial control, the transverse control is determined through solutions to a two-point boundary value problem. Numerical results from a six degree-of-freedom simulation which used the decoupled control indicate that it is better than the completely Cartesian coordinate control for most of the cases considered. Decoupled control, though, is obtained iteratively through a two-point …

Nebraska Summary: S125 Massey Ferguson 3670, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Nebraska Summary: S111 Lamborghini 115 Vdt, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Nebraska Summary: S102 Ford 3430 8x8, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Nebraska Summary: S101 John Deere 3255, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Nebraska Summary: S104 Ford 4630 8x8, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Nebraska Summary: S137 Zetor 9540, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Nebraska Summary: S338 Hurlimann 6135, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Nebraska Summary S111: Lamborghini 115v Dt Also White 6105c And 6105ca, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Identification Of Tetragonal And Cubic Structures Of Zirconia Using Synchrotron X-Radiation Source, Ram Srinivasan, Robert J. De Angelis, Gene Ice, Burtron H. Davis

Department of Mechanical and Materials Engineering: Faculty Publications

X-ray diffraction from a synchrotron source was employed in an attempt to identify the crystal structures in zirconia ceramics produced by the sol-gel method. The particles of chemically precipitated zirconia, after calcination below 600 °C, are very fine, and have a diffracting particle size in the range of 7-15 nm. As the tetragonal and cubic structures of zirconia have similar lattice parameters, it is difficult to distinguish between the two. The tetragonal structure can be identified only by the characteristic splittings of the Bragg profiles from the "c" index planes. However, these split Bragg peaks from the tetragonal phase in …

Test 1648: Ford 8830 Powershift Diesel 18-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF THE TEST PROCEDURE General Tractors are tested at the University of Nebraska according to the Agricultural Tractor Test Code approved by the American Society of Agricultural Engineers and the Society of Automotive Engineers or official Nebraska test procedure. The manufacturer selects the tractor to be tested and certifies that it is a stock model. Each tractor is equipped with the common power consuming accessories such as power steering, power lift pump, generator, etc., if available. Power consuming accessories may be disconnected only when the means for disconnecting can be reached from the operating station. An official representative of …

Test 1653: Caterpiller Challenger 65b And 65c Diesel 10-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF THE TEST PROCEDURE General Tractors are tested at the University of Nebraska according to the Agricultural Tractor Test Code approved by the American Society of Agricultural Engineers and the Society of Automotive Engineers or official Nebraska test procedure. The manufacturer selects the tractor to be tested and certifies that it is a stock model. Each tractor is equipped with the common power consuming accessories such as power steering, power lift pump, generator, etc., if available. Power consuming accessories may be disconnected only when the means for disconnecting can be reached from the operating station. An official representative of …

Test 1655: Belarus 572, 505, 525 And 570 Diesel 18-Speeds, Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF THE TEST PROCEDURE General Tractors are tested at the University of Nebraska according to the Agricultural Tractor Test Code approved by the American Society of Agricultural Engineers and the Society of Automotive Engineers or official Nebraska test procedure. The manufacturer selects the tractor to be tested and certifies that it is a stock model. Each tractor is equipped with the common power consuming accessories such as power steering, power lift pump, generator, etc., if available. Power consuming accessories may be disconnected only when the means for disconnecting can be reached from the operating station. An official representative of …