Engineering Commons^™

A Study On The Causes Of Variations In Transmissivity And Storativity During Pump Tests At Asylum Lake, Paul Joseph Pare

Masters Theses

Over a two year period, Western Michigan University ran a number of pump tests in the Asylum Lake Area in Kalamazoo, Michigan. The transmissivities and storativities calculated from these tests differed significantly from well to well in any particular test, and from pump test to pump test. Utilizing the computer programs AQTESOLV 3.0 and Aquifer Parameter Estimator, a number of T and S values were calculated. After analysis of the results, the following conclusion was drawn. The main reason for the deviations in the T and S values arose from the mixing of the results of numerous methods (some of …

Dynamic Pulse Buckling Of Columns With Viscous Damping, Murli Kadandale

Masters Theses

This is a study of dynamic pulse buckling of columns with viscous damping. The differential equations of motion were obtained using the Bemoulli-Navier hypothesis. The effects of axial and rotary inertia were included in the analysis. The Voigt-Kelvin model for a viscoelastic material is used. The Finite Difference Method was employed to solve the differential equations of motion. First columns without geometrical imperfections were studied, and a correlation between the damping modulus and the more familiar damping ratio was obtained. Then beams with initial geometrical imperfection were studied. A suitable dynamic buckling criterion was defined. It was observed that viscous …

Cumulative Average Pricing Method For Estimating Average Service Life, Mahendra Babu Hosangadi

Masters Theses

The study determined if accuracy of estimation of retirement price of industrial equipment was affected by using a cumulative average pricing (CAP) method at varying conditions of inflation rate, service life, and life characteristics. The study also determined the accuracy of estimating the average life of unaged data by simulated plant record (SPR) method. Thirty-six experiments were conducted at varying conditions of inflation rate, curve type and average life. The study was conducted for two left modal curves, two symmetrical modal curves and two right modal curves at 20 and 40 years average life using three different inflation rates: 3%, …

An Investigation Of Turbulent Taylor-Couette Flow Using Laser Doppler Velocimetry In A Refractive Index Matched Facility, Joseph C. Parker

Masters Theses

Turbulent Taylor-Couette flow between an annulus formed by two concentric cylinders with dead end walls is comprised of complex patterns of vortices. An experimental apparatus was designed to provide refractive index matching between the annulus and working fluid. Optical access was maintained through three sides of the annulus and one end wall. An aqueous solution of sodium iodide was formulated to match the refractive index of the Plexiglas annulus. Laser Doppler Velocimetry was used to measure the three components of velocity and turbulence intensity throughout a planar section in the annulus. The annulus dimensions were: ƞ= 0.672, d = 15.08 …

The Effect Of Rotor Wake/Exit Guide Vane Interaction On The Total Pressure Losses In An Airfoil Cascade, Aaron Mosebach

Masters Theses

Computational simulations have been performed to study the effects of unsteady rotor wakes on the total pressure losses and the boundary layer characteristics in a compressor cascade. In the numerical simulations, transitional and turbulent flow conditions were modeled at design and off-design inlet flow angles, and for varying rotor wake widths and wake velocity deficits.

First, simulations were performed in the absence of rotor wakes at the inlet of the EGV (Exit Guide Vane) cascade. Second, simulations were performed for different wake width and wake velocity deficit values at the inlet of the EGV cascade. The majority of the numerical …

Monitoring And Prognosis Of Plant Components, Jeffrey Banks

Masters Theses

Many predictive maintenance approaches focus primarily on fault monitoring and diagnosis of rotating machinery. Today's industrial "reliability-based" maintenance programs implement vibrational analysis techniques as a sound foundation in minimizing unnecessary machine downtime. These approaches, based upon on-line data acquisitions and analysis may be used to increase component availability and ultimately forecast remaining life. Depending upon the specific type of machinery under consideration, measurements such as temperature, voltage, current, rotational speed, power, and torque may be analyzed to enhance machinery diagnostics capability.

The purpose of the proposed research is to formulate and implement a methodology to estimate the remaining useful life …

Addition Of Automatic Dimensioning Feature To D-M-E’S Ultimate Mold Base Design Software, Cori L. Brown

Masters Theses

There have been many improvements in the plastics industry over the past few years. One of these areas is in the design of injection molds. This area has been enhanced by the use of Computer-Aided Design systems and furthered by the creation of specialized mold design software. The Ultimate^® design system from D-M-E has made a mold designer's job much easier by automating much of this process. This project extends the function of this software by adding an automatic dimensioning feature that will make the mold design process less tedious and less time consuming. This addition will also standardize …

Development Of A Mold Trial Procedure For Establishing A Robust Process, Marc R. Vander Kooi

Masters Theses

To reduce variation in the injection molding process it is essential to understand the effect of process, mold, and material variables on critical part characteristics. Gaining a thorough understanding of these variables is often difficult due to the limited time manufacturers typically have available for mold trials. To address this issue, the Premier Class Injection Molding consortium (PCIM) has performed numerous experiments relating to shot-to-shot repeatability. Using the PCIM data set and experimentation procedures as a base, a procedure was developed to collect data during a mold trial. Incorporating small experiments and statistical analysis, the new procedure allows meaningful data …

Modeling And Development Of A Cellular Micro-Kernel, K. Balaji

Masters Theses

A novel cellular load distribution strategy was designed and implemented on transputers by Dr. Richard Taylor and Dr. Don Goodeve at the University of York, United Kingdom. Based upon the above proposed strategy, a statistical model was developed using the Cellular Automata Theory. The theoretical model drives the implementation process of the cellular micro-kernel on the nCUBE 2S system. The load distribution and the performance characteristics for snake and L type transmission modes, and for uniform and non-uniform distribution of destination processors of the micro-kernel has been measured and compared with our theoretical model. The results show good agreement between …

A Comparative Study Of The Stress Concentration Factors Arising Between Two Equal, Nearly Intersecting, Perpendicular, Pressurized Holes In An Infinite Solid With Those Arising Due To An Infinite Series Of Such Holes, Paul J. Drogowski

Masters Theses

Finite element analysis is used to determine the stress concentration factors arising from two equal, perpendicular, nearly intersecting, pressurized holes in an infinite solid while varying the distance and pressure ratios between the holes. The results are compared and contrasted with those previously obtained for an infinite series of such holes. A ratio of the distance between the holes to the diameter of the holes at which the holes can be considered to be single holes in an infinite solid is determined. A study is performed to determine a correlation between the location of the region of maximum stress and …

Hardware/Software Codesign And Simulation With The Occam Programming Language, Roy L. Krans

Masters Theses

Hardware/software codesign is an increasingly popular method for improving system performance and adaptability while minimizing cost. The goal of this design approach is to achieve the desired system characteristics (performance, fault tolerance, cost, power consumption, etc.) by carefully distributing the system functions among hardware and software components. Popular tools for describing this dual hardware/software functionality are behavioral languages such as C++ and Ada. These languages typically include facilities for both traditional sequential programming as well as behavioral modeling.

This thesis examines the effectiveness of occam as a behavioral language and its role in hardware/software codesign. The occam language is used …

Eigenproperties Of Nonclassically Damped Dynamic Systems, Daniel Patrick Malone

Masters Theses

"This thesis develops perturbation series solutions for the eigenvalues and eigenvectors of nonclassically damped dynamic systems for the case where the unperturbed system has repeated eigenvalues. The case of repeated eigenvalues is much more complicated than the case of perturbing a system with distinct eigenvalues. Because of this difficulty, only a specific category of dynamic systems with repeated eigenvalues is addressed. Namely, only those systems that when perturbed have series solutions of the form of a power series. This category of systems can be easily identified by an a priori check developed in the application section of this thesis. The …

A Neural Network Thrust Force Controller To Minimize Delamination During Drilling In Graphite Epoxy Laminates, Robert B. Stone

Masters Theses

"Delamination is a well-recognized problem associated with drilling in fiber-reinforced composite materials (FRCM). The most noted problems occur as the drill enters and exits the FRCM. Since drilling is often a final operation during assembly, any defects introduced in parts by drilling represent an expensive loss. Studies based on linear elastic fracture mechanics theory have proposed critical thrust forces in the various drilling regions that will prevent crack growth or delamination. Using these critical thrust force curves as a guide, a thrust force controller was developed to minimize the delamination while drilling in graphite epoxy laminates. A neural network control …

Iron Phosphate Glasses As A Potential Nuclear Waste Disposal Medium, Melissa G. Mesko

Masters Theses

”Phosphate glasses containing large amounts of Fe₂O₃ (up to 43wt%) were studied to determine their potential suitability as nuclear waste disposal glasses for high level radioactive wastes containing large concentrations of iron oxide, phosphate, and fluoride compounds. Glass formation and chemical durability was the prime focus of this study, while properties such as density, thermal expansion, dilatometric softening temperature, and devitrification temperature were examined as well. It was found that large amounts of simulated nuclear waste material (up to 44.4wt% Cs₂O or 37.5wt% SrO) could be incorporated into the base iron phosphate glass while retaining …

Effects Of Specimen Size Reduction On The Transition Curve Of The Charpy V-Notch Impact Test, Lonnie Eugene Schubert

Masters Theses

"This study was undertaken to correlate the impact properties of ASTM standard full size Charpy V-notch impact specimens to the impact properties of subsize specimens. An ASTM A533-B quenched and tempered plate steel was examined. The fine grained martensitic material had a coarse prior austenite grain size, which resulted in a low upper shelf energy for this material. Three sizes of specimens were included. Specimens were irradiated in the TRIGA Reactor Facility operated by the U. S. Geological Survey in Denver, Colorado, to 1 x 10¹⁹ n/cm² (E > 1 MeV) at 150°C (302°F). Unirradiated and irradiated specimens were …

Thermoplastic Composites Of Recycled High Density Polyethylene And Recycled Tire Particles, James N. Mckirahan Jr.

Masters Theses

This study identified the mechanical properties and processibility of composite materials of recycled high density polyethylene (HDPE), recycled rubber tire particles, and/or ethyl co-vinyl acetate and poly (e-caprolactone). The composites were processed using a single screw extrusion system.

Three groups of experiments were conducted, on the composites in their extruded form to investigate the mechanical properties of ultimate tensile strength, percent elongation, and hardness. The first experiment investigated the effect of recycled rubber particle concentration in the composites up to 25 percent. The second experiment investigated the effect of recycled rubber particle size on the composites of recycled HDPE and …

Nonlinear Finite Element Micromechanic Analysis Of Thermoplastic Composite Of Recycled High Density Polyethylene Reinforced With Short Glass Fibers, Qiming Lou

Masters Theses

This thesis studied the nonlinear micromechanic behavior of thermoplastic composite of recycled high density polyethylene (HDPE) reinforced with short glass fibers using finite element method. The composite material was modeled using a micromechanic unit cell to simulate the stress distribution between the plastic matrix and the fiber in the composite. Nonlinear behavior of recycled HDPE and imperfect bonding between the fiber and matrix were investigated. Load-bearing capability of the fiber was evaluated using stress partition ratio (SPR) in the composite models. The effect of fiber aspect ratio on the stress distribution of the composite was studied to optimize the material …