Engineering Commons^™

Experimental Investigation Of Submerged, Turbulent, Axisymmetric Air Jet Impinging On A Flat Plate, Lan Xiao

Theses

Experimental investigation was carried out on the flow characteristics of a circular, submerged, turbulent, axisymmetric air jet impinging normally on a smooth, flat, square, Lucite plate and a sand paper covered plate. Jet issuing from a circular nozzle of 0.5 inch diameter while the Reynolds Number varying from 10,000 to 85,000 was investigated. The flow can be considered incompressible since the pressure and the velocity of the jet were not too high, with Mach Number of the order of 0.3.

Various flow parameters were measured to obtain the velocity and pressure distributions at the surface of the flat Lucite plate, …

Detection Of Planar Facets In Noisy Range Images, Ajey S. Atre

Theses

Segmentation of the image is one of the major tasks of a machine vision system designed for constructing a three-dimensional representation of the object being imaged. A robust approach for segmenting planar surfaces from range images is presented in this paper. An algorithm based on clustering through fuzzy covariance matrices, which has been proposed by Gustafson and Kessel is considered for planar segmentation. However this algorithm performs poorly if the data is noisy, which is usually the case in real life applications. In order to handle noisy data, a robust modification, based on the "noise clustering" concept, is introduced to …

Vibratory Size Segregation Of Particulate Matter, Anthony La Rosa

Theses

Size segregation imposed by vibration or shaking is an ubiquitous phenomenon whereby a large particle will rise to the top of a bed of smaller spheres upon vibration. Several mechanisms based on computer simulations have been proposed, however a complete theory remains elusive. The objective of this study was to perform experiments to study vibratory segregation of particles for varying size ratios and vibration parameters. More specifically, the rise time of a sphere from the bottom to the top of a vibrated bed was examined. It was found that the rise time decreased with an increase in amplitude for fixed …

Local Stress Factors Of Pipe-Nozzle Due To Radial Load, Circumferential And Longitudinal Moments, Junyu Lin

Theses

This thesis presents a series of stress factor data which provide more detailed information for the calculation of local stresses at the nozzle region, as well as the pipe region, of a pipe-nozzle intersection, subjected to an external radial load, circumferential bending moment, and longitudinal bending moment, respectively.

The pipe and nozzle thicknesses are assumed to be identical. Numerical solutions are obtained through the use of the finite element method. In obtaining the numerical solutions via ANSYS, the quadrilateral element is used to simulate the thin shell pipe-nozzle geometries. The local stresses, at eight different points on both the pipe …

An Application Of Neural Networks To Statistical Process Control, Asterios Papaikonomou

Theses

Recent changes in the past World War II economy have produced a more educated, value driven customer. A global economy has emerged to technological advances which has made competition fierce as well as proximate. As a result, manufacturing companies are required to provide consumers with quality products at a reasonable cost. A quality product is defined as one that fulfills the needs and expectations of the consumer and provides him with a sense of value.

Since all companies want to provide quality products, the reason why poor quality is sometimes the result is not the outcome of actions for that …

Evaluation Of Collision Properties Of Spheres Using High-Speed Video Analysis, Jian Yu

Theses

Experimental evaluation of the collision properties of spheres is performed using video image analysis techniques. A high-speed Kodak EktaPro1000 video camera is utilized to record a collision sequence between two spheres at 1000 frames/sec, and then the images are analyzed to calculate three dimensional translation and rotation before and after the collision. These quantities are used to compute the collision properties for a pair of one inch nylon spheres, i.e. the coefficient of friction, and the coefficients of normal and tangential restitution. The focus of the thesis is on image analysis techniques that provide high accuracy results even though the …

Set-Up Saving Schemes For Printed Circuit Boards Assembly, Oded Z. Maimon, Ezey M. Dar-El, Tali F. Carmon

Industrial and Manufacturing Engineering

Focusing on a basic printed circuit board (PCB) assembly line configuration characterized by very long set-up times, we examine two scheduling methods that can significantly reduce the set-up. Both methods -the Grouped Set-Up (GSU) method that has been recently introduced in the literature and the Sequence Dependent Scheduling (SDS) method, which has not been studied in this context -are based on component commonality among PCB types. Using the typical traditional scheduling method as a benchmark, the GSU and the SDS methods are compared in terms of three performance measures: line throughput, average work-in-process (WIP) inventory level, and implementation complexity. Guidelines …

Minutes Of Tractor Test Museum Committee October 21, 1993, Tractor Museum

Lester F. Larsen Tractor Museum: Planning and Development Documents

Status of using tractor test building. Organizing Friends of the Tractor Test Museum

Notes From Museum Committee Meeting October, 1993, Tractor Museum

Lester F. Larsen Tractor Museum: Planning and Development Documents

No abstract provided.

Froth Flotation Apparatus, Jiann-Yang Hwang

Michigan Tech Patents

The froth flotation apparatus includes a gas bubble-particle contact unit including a mixing structure for breaking a gas into fine bubbles,such as a packed tower packing or mechanical agitator, and a separate phase separation unit. A conditioned aqueous pulp containing a mixture of hydrophobic and hydrophilic particles and a substantially inert gas, such as air, are introduced into and combined in one end of the contact unit and subsequently flow concurrently through the mixing structure, such that the gas is broken into fine bubbles which intimately contact and become attached to the hydro- phobic particles. The resulting gas bubble-particle mixture …

Statistical, Random And Fractal Characterizations Of Surface Topography With Engineering Applications, Gongyao Zhou

Dissertations

Two methods, namely the conventional and fractal geometry methods, are developed for surface topography characterization. The conventional method utilizing statistical and random process techniques is used to study waterjet machined surfaces. In the study the waterjet surfaces are separated into smooth and striation zones, where striation influence is negligible in the smooth zone. It is found that the smooth zone has a random, moderately isotropic texture, with the height distribution nearly Gaussian. In the striation zone the major frequencies of the surface profile power spectra are independent of cutting parameters, while the amplitudes of these frequencies monotonically increase with cutting …

Ole Miss Engineer 1993

Ole Miss Engineer

No abstract provided.

Computation Of The Aerodynamic Characteristics Of A Subsonic Transport Aircraft Using A Panel Method, Lillianne Plaster Whitelock Troeger

Mechanical & Aerospace Engineering Theses & Dissertations

An advanced low-order panel method, VSAERO, is applied to a full-configuration transport aircraft. Wing pressure distributions as well as lift, drag, and pitching moment coefficients calculated for the full computational configuration are compared with experimental data. In addition, partial configurations are evaluated computationally to determine the relevance of certain complex aircraft components to the computations. It is shown that the wing-surface pressure distributions and pitching moment coefficient are well predicted by VSAERO. The lift coefficient is consistently overpredicted by the code.

Emissions Studies For A Natural Gas-Fired Internal Combustion Engine, Carlos M. Buitrago

Mechanical & Aerospace Engineering Theses & Dissertations

Since 1991, a University owned truck has been operating with natural gas. In order to improve emissions performance a different fuel management strategy was developed. With the help of Siemens Automotive in Newport News, VA, a liquid fuel injector was modified to handle natural gas. The basic engine was tested to determine the benefits in emissions that the multi-point injection system can have over the single point injection system that had been used previously. Pre-catalyst, raw exhaust-gas data for the more important pollutants were taken and analyzed in both systems under different loads and intake manifold pressures. In addition, to …

Simultaneous Aerodynamic Analysis And Design Optimization, Satish Venkatasubra Mani

Mechanical & Aerospace Engineering Theses & Dissertations

An efficient approach for simultaneous aerodynamic analysis and design optimization is presented. Using this approach, the expensive procedure of performing complete steady— state flow analyses at every design-optimization step is avoided, thus addressing the challenge of incorporating computational fluid dynamics software into efficient gradient—based optimization techniques for aerodynamic design. An adjoint—variable method is introduced to nullify the effect of an increased number of design variables in this problem formulation. This approach is successfully tested on two quasi—one—dimensional nozzle—flow problems: a fully supersonic flow, and also a transonic flow with a normal shock. The algorithm is implemented using the direct Newton—iteration …

Acoustic Correlates Of Vowel Perception As Determined From Synthesis Experiments With Multi-Tone Stimuli, Zhongjiang Zhang

Electrical & Computer Engineering Theses & Dissertations

An essential requirement of speech signal processing is to extract information (features or parameters) from the speech signal which encode the information carried by the signal. The objective of this thesis work was to examine and evaluate two feature sets as acoustic correlates for vowel perception. They are formants and DCTCs. Formants are the frequencies of spectral peaks of the speech signal. DCTCs are the Discrete Cosine Transform Coefficients of the magnitude spectrum and are thus features which encode the global spectral shape of speech signal.

There are different opinions regarding which feature set is a more accurate representation for …

A New Adjoint Variable Method For The Sensitivity Analysis Of Dynamic Responses, Krishnamoorthy Ramesh

Mechanical & Aerospace Engineering Theses & Dissertations

A new adjoint variable method has been formulated for finding the sensitivity derivatives of dynamic system responses. Though the method can be based on any step-by-step time marching scheme, the Wilson Theta Method has been chosen as the basis of the new formulation . Wilson Theta Method is an implicit numerical integration scheme for finding the dynamic system responses. The new formulation uses the differential form of equations of motion as given by the Wilson Theta Method in its formulation of the adjoint equation. The conventional methods used for finding the sensitivity derivatives, namely, the direct differentiation technique, the central …

Numerical Simulation Of Two-Dimensional, Spatially Developing Mixing Layers, Robert V. Wilson

Mechanical & Aerospace Engineering Theses & Dissertations

Numerical simulation of a forced, two-dimensional, spatially-developing mixing layer using a control-volume formulation is performed. Three classes of forcing functions are used at the inlet boundary which are; (i) steady boundary conditions, (ii) combinations of the fundamental, first subharmonic, and second subharmonic modes from linear inviscid stability theory, and (iii) a broad spectrum of modes whose velocity power spectrum and transverse turbulence intensity relationship is taken from experiment. The results show that shear layer rollup occurs for time-dependent inlet boundary conditions and that the resulting vortex dynamics are determined from the subharmonic content of the inlet boundary conditions. It is …

Accurate Evaluation Of Homogeneous And Nonhomogeneous Gas Emissivities, Kam-Pui Lee

Mechanical & Aerospace Engineering Theses & Dissertations

Spectral transmittance and total band absorptance of selected infrared bands of carbon dioxide and water vapor are calculated by using the line-by-line and quasi-random band models and these are compared with available experimental results to establish the validity of the quasi-random band model. Various wide-band model correlations (such as Edwards and Balakrishnan, Tien and Lowder, and Felske and Tien) are employed to calculate the total band absorptance and total emissivity of these two gases under homogeneous and nonhomogeneous conditions. These results are compared with available experimental results under identical conditions. From these comparisons. it is found that the quasi-random band …

Book Review, Suzanne B. Watson

RISK: Health, Safety & Environment (1990-2002)

Review of the book: HELENA SZEJNWALD BROWN, ET AL., CORPORATE ENVIRONMENTALISM IN A GLOBAL ECONOMY: SOCIETAL VALUES IN INTERNATIONAL TECHNOLOGY TRANSFER. (Quorum Books 1993) [264 pp.] Acknowledgments, bibliography, figures, index, tables. LC 92- 19851; ISBN: 0-89930-802-3. [$49.95. P.O. Box 5007, Westport CT 06881.]

Integration Of Simulation Modeling And Computer Aided Production Management In Computer Integrated Enterprise, Emine Persentili, Sema E. Alptekin

Industrial and Manufacturing Engineering

Designing efficient and integrated manufacturing systems is the first step in attaining computer integrated enterprises (CIE). Integration of planning and implementation phases of manufacturing is essential for taking full advantage of the CIE. In order to design reliable and efficient manufacturing systems, the designers must consider the impacts of planning decisions made by computer aided production management (CAPM) modules on implementations held in manufacturing cells. This paper focuses on two issues. The first issue is importance and necessity of integrating CAPM modules with manufacturing cells. The second issue includes major features of the object-oriented approach and their relevance to our …

A Kalina Cycle Application For Power Generation, Mounir B. Ibrahim, Ronald M. Kovach

Mechanical Engineering Faculty Publications

A multi-component (NB₃/H₂O) Kalina-type cycle that utilizes the exhaust from a gas turbine is investigaed in this paper. The turbine-inlet pressure of 5.96 × 10⁶N/m² and temperature of 755.372 K were kept constant, as well as the working fluid temperature at the condenser outlet (at 290K). The HN₃ mass fraction at the turbine inlet was varied along with the seperator temperature and the effects on the cycle efficiency were studied. The relationships between turbine-inlet flow and the seperator-inlet. How are shown in addition to the upper and lower HN₃ mass-fraction bounds. …

Transient Flowmeter Calibration Facility, Paul J. Lefebvre, William W. Durgin

Office of the Provost Scholarship

An apparatus for defining the free surface of a moving column of a fluid in a vertical pipe to enhance the accuracy of measurements of transient rate of flow of the fluid using electromagnetic flowmeter is described. It provides a neutrally buoyant plug which stays in contact with the free surface of the column of the fluid at all times and thus defines the free surface of the fluid moving in the vertical pipe accurately and reduces the oscillations of the free surface of the fluid.

Advanced Aeronatics Design: Project Based Engineering Education At Wpi, D. J. Olinger, William W. Durgin, Andreas N. Alexandrou

Office of the Provost Scholarship

One element of WPI's project-based curriculum is its interdisciplinary Advanced Aeronautics Design Program. Students participating in the program are involved in the design, construction, and flight testing of non-traditional aircraft such as an ultralight solar-powered vehicle, microwave-powered long endurance aircraft, or a flying oblique wing. The WPI project philosophy and character are described and illustrated using examples from the AAD program.

Laboratory Testing Of The Reflectance Properties Of Roofing Materials, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

Past simulation and test cell studies have shown potential reduction to building cooling loads from higher exterior surface solar reflectances (Givoni and Hoffman, 1968; Givoni, 1976; Chuan and Busching, 1983; Griggs and Shipp, 1988; Anderson, 1989; Akbari et al., 1990; Chandra and Moalla, 1991; Bansal et al., 1992). Furthermore, simulation analysis of macro-climatic effects have shown that light colored surfaces may reduce the magnitude of the urban heat island (Taha et al., 1988; Akbari et al, 1989; Akbari et al., 1992).

Figure 1 shows a graphic illustration of the potential influence of surface reflectance on roof solar heat gain. The …

Proposed Smoothing Technique To Avoid Numerical Instabilities In A Hydrodynamic Numerical Model, Thomas P. Abraham

Electronic Theses and Dissertations

Despite every effort being made to produce a completely problem-free computational model, no breakthrough has yet been made. When a numerical model is used to solve a real world problem, there is a tendency for the non-physical spurious waves to creep in. If these waves are not checked, they can lead to serious instability problems. Once these waves are removed, the model should be able to simulate physical phenomenon like circulation, separation, flow reversal in the vertical plane, mixing/transport, convection/diffusion, etc.

When a numerical mode] is made to run for a certain period of time, node-to-node oscillations may arise and …

Analysis Of Sandwich Plates Subjected To Blast Loading, Vijay Prasad Bulla

Masters Theses

A dynamic analysis is presented for the bending response of square sandwich plates with isotropic core and facings under blast type pressure. The maximum central deflections of simply supported plates under static and dynamic loadings are compared for various thicknesses and elastic moduli. The deviation of the thick sandwich plate results from the pure-bending theory results is presented for various core properties. Small deflection dynamic iso-response plots are shown for different core rigidities. To study the limits of small deformation linearity for various sandwich plates, non-linear results for deformations under high pressure loads are compared with the linear results. The …

Rolling Friction Research Instrument, John P. Ward

Masters Theses

An instrument has been analyzed, designed and constructed that will accurately measure the rolling resistance of metallic spheres an plane surfaces subjected to normal loading which will produce contact stresses approaching material yield.

Wet Process For Fly Ash Beneficiation, Jiann-Yang Hwang

Michigan Tech Patents

A wet process for the beneficiation of a fly ash by-product has the following steps: a) forming a slurry mixture of a fly ash material and a liquid; b) gravitationally separating and collecting a first material fraction of the fly ash having a density less than the liquid by skimming off floating slurry material; c) separating a first magnetic fraction from the slurry by subjecting the slurry to a magnetic field of from about 300 gauss to about 10 kilogauss; d) separating the unbumed carbon from the remaining slurry components by adding an effective amount of an oil having a …

Exergetic Cost Analysis Of A Mechanical Exergy Recycle, Jim Mcgovern

Conference Papers

A mechanical plant that involves an exergy recycle is presented for analysis. It consists of gearboxes and a fluid coupling. There is one input of shaft power to the plant and there are three separate outputs of shaft power. An exergetic cost analysis approach is outlined and applied to the plant.