Engineering Commons^™

Deformation Manifold Learning Model For Multi Walled Carbon Nanotubes, Shashank S. Pathrudkar

Dissertations, Master's Theses and Master's Reports

Two-Dimensional (2D) materials are being studied widely by researchers due to their superior material properties over the bulk materials. Since the isolation of graphene in 2004, graphene has gained popularity amongst the 2D materials community. Graphene when rolled into sheets form Carbon Nanotubes (CNTs) which possess excellent mechanical and electrical properties. Concentric stacks of CNTs yield Multi-walled Carbon Nanotubes (MWCNTs) which are superior to CNTs in certain aspects. It has been well established that the deformation of CNTs and MWCNTs change their mechanical and electrical properties significantly. This has opened doors for CNTs into numerous applications and also piqued the …

Transient Maneuvers And Pressure Analysis On An Automotive Torque Converter, Abigail A. Hempy

Dissertations, Master's Theses and Master's Reports

This work involves an investigation of internal fluid behavior of an automotive torque converter in a front-wheel drive automatic 6-speed transmission. The fluid behavior is identified through 29 pressure transducers instrumented throughout the torus, acquired through IR Telemetrics multiplexed channels, and analyzed with custom MATLAB code. The main vehicle operating conditions studied in this research are back drive scenarios or low motoring torques. Findings showed speed and torque limits for open converter coast down conditions as well as pressure field behavior with negative input torque.

Base Vibration Effects On Additive Manufactured Part Quality: A Study Of 3d Printing Onboard U.S. Navy Ships, Nick Jensen

Dissertations, Master's Theses and Master's Reports

The current landscape of manufacturing is evolving because of technology like additive manufacturing (AM). The mobility and compactness of AM are what make it desirable for many industry sectors. The U.S. Navy has shown interest in deploying AM on ships as it could alleviate their dependency on off-route docking to recharge supplies. However, the U.S. Navy's aspiration is currently hindered due to harsh ship-borne environments that degrade AM part quality.

This thesis focuses on vertical base vibration effects on AM part quality. An introduction is first given in Chapter 1 to familiarize the reader with the U.S. Navy's predicament. The …

Novel New Modeling Procedure For Industrial Machinery With Nonlinear Connections, Steven Whitican

Dissertations, Master's Theses and Master's Reports

Given current timelines for rolling out production at volume, the ability to model portions of the production process is of paramount importance. To model production, high-fidelity models of production assets must be obtained. The production assets are comprised of linear and nonlinear structures. The linear structures are well understood and defined. Significant work has, and is, being done to understand the nonlinear components. This work focuses on developing and correlating a model of a nonlinear component. The component studied and modeled is a linear guide. Linear guides are bearings which facilitate translational motion of machine axes. An accurate model of …

Multi-Dimensional Modeling For Environmental Impact Assessment At Intersections Of The Food-Energy-Water Nexus, Jessica Daignault

Dissertations, Master's Theses and Master's Reports

This dissertation uses multi-dimensional modeling for environmental impact assessment at intersections of the Food-Energy-Water (FEW) Nexus, including life cycle assessment (LCA) modeling for quantification of environmental impacts due to household FEW consumption, a linear regression framework for quantification of water-use impacts of marginal electricity generation, and a multi-objective optimization model to assess monetization of water withdrawals for electricity generation and impacts to water stress due to electricity dispatch schemes. Chapter 2 of this dissertation summarizes the development of an LCA model that quantifies the direct and indirect environmental impacts of household FEW consumption. The model is executed through a novel …

Local Watershed Analysis For Hubbell And Lake Linden, Michigan, Brittany Hubbard

Dissertations, Master's Theses and Master's Reports

This report analyzes flood frequency risk, examines drainage, and delineates local level watershed characteristics for the Site located in western HUC 12-040201 030304 Torch Lake Subwatershed. Specifically, unnamed catchments in need of HUC-14 or HUC-16 local level delineation are evaluated to determine the effects of excess runoff on the cities of Hubbell and Lake Linden, Michigan. Further, this report aims to identify the location of known or suspected historical and current drainage infrastructure, and to prioritize locations for low-impact sustainable designs that reduce excess runoff and provide flood protection for these lakeshore communities.

Sensing Methods For Two-Target And Four-Target Detection In Time-Constrained Vector Poisson And Gaussian Channels, Muhammad Fahad

Dissertations, Master's Theses and Master's Reports

In this dissertation we consider a sensor scheduling or resource management problem for a vector Poisson and Gaussian channels. The input is a binary random vector and the output is a set of conditionally independent Poisson or Gaussian random variables. The objective is to design a scaling matrix, which is a linear transformation whose purpose is to entangle the different inputs, under a total given energy/time constraint. The two metrics are adopted to quantify the performance of the designed scaling matrix: mutual information and Bayesian inference. In other words, it is an experimental design problem where the objective is to …

Active Gravity Offloading System With Infrared Tracking For Rover Testing, Travis Wavrunek

Dissertations, Master's Theses and Master's Reports

Gravity offloading is a tool used to test how different gravitational forces will impact the mobility of rovers bound for Lunar or Martian expeditions. Previous approaches have been successful in simulating partial gravity environments, and this report details how the Infrared- Gravity offload (IRGO) system, developed for the Planetary Surface Technology Development Laboratory (PSTDL) and lunar simulant sandbox, has a similar aim. Through a series of iterations, IRGO has been developed to actively track an infrared beacon and follow a rover within the test chamber to eliminate inertial and friction forces along two horizonal axes. A portion of a rover’s …

Marangoni Propulsion Of Active Particles, Saeed Jafari Kang

Dissertations, Master's Theses and Master's Reports

We study the surfing motion of active particles located at a flat liquid-gas interface. The particles create and maintain a surface tension gradient by asymmetrically discharging a surface tension-reducing agent. We employ theory and numerical simulation to investigate the Marangoni propulsion of these active surfers. First, we use the reciprocal theorem to establish a relationship between the propulsion speed and the release of the active chemical. This theoretical relation is utilized to examine the effect of wall confinement and geometry on the Marangoni-driven motion of active particle when the inertial effects are negligible and when the transports of the released …

Experimental Evaluation And Simulation Of Torque Transmissibility Frequency Response Functions Of Vibration Isolators And Absorbers For Drivetrain Applications, Luke Jurmu

Dissertations, Master's Theses and Master's Reports

Four studies involving torsional vibration isolation performance of automotive drivetrain components, make up this dissertation. One study features a prototype planetary torsional vibration absorber, a unique device that targets low frequency torsion modes in automotive drivetrains. Two studies feature experiments on several torque converters, clutch locked and open, to validate models of the hardware. The last study details experiments on a centrifugal pendulum absorber in a torque converter, to characterize the viscous friction while submerged in automatic transmission fluid (ATF). The enclosed studies improve the state of the art of drivetrain vibration absorbers and isolators, by introducing a new vibration …

Understanding The Weather- And Soil-Related Variability In Agricultural Water Footprints: Case Study Of Maize And Soybeans Grown In The St. Joseph Watershed, Karleigh M. Krieg

Dissertations, Master's Theses and Master's Reports

Introduced in 2002, the water footprint is a valuable tool for understanding the consumption of freshwater resources. The traditional approach to quantifying the water footprint is to sum the green, blue, and gray water footprint components. The green water footprint is the volume of water that comes from precipitation, is stored in the soil, and used by vegetation. The blue water footprint is the volume of surface or ground water that is withdrawn and applied to cultivated lands via irrigation. These components are based on the evapotranspiration of green and blue water resources, respectively. The gray water footprint is the …

An Overview Of Converting Kabul’S Traffic Circles And Rotaries To Modern Roundabouts, Mohammad Anas Taeb

Dissertations, Master's Theses and Master's Reports

Circular intersections, in the form of traffic circles and rotaries, were built around the world in the first half of the twentieth century. However, with the rise in traffic flow, regular traffic congestion and accidents forced authorities to look for alternative solutions and, in many cases, signalized intersections became the preferred alternative. In the 1960s, the UK introduced concept of modern roundabouts and a new set of priority rules for the circulating traffic. Since the inception of modern roundabouts, they have enhanced both operational and safety aspects at these locations, even when used to replace large traffic circles/rotaries, proving that …

Commissioning And Testing Of A New Dusty Thermal Vacuum Chamber, Ben Wiegand

Dissertations, Master's Theses and Master's Reports

The Dusty Thermal Vacuum Chamber (DTVAC) is a new facility purchased by the Planetary Surface Technology Development Lab (PSTDL) that will be used to test the Technology Readiness Level (TRL) of extraplanetary devices and systems. With the use of vacuum pumps and simulated regolith, the DTVAC can create extraplanetary environments such as those found on the Moon and Mars. This report details the actions that were taken to prepare the DTVAC for TRL testing, including the development of a Data Acquisition Center (DAC) and test fixtures, along with the findings of baseline tests that were performed to understand the behavior …

Towards Systems On Cloth: The Design, Manufacturing, And Validation Of Open-Source Embroidered Resistors, Somerset Schrock

Dissertations, Master's Theses and Master's Reports

This thesis is focused on advancing embroidered wearable electronics and textile electronics by creating open-source flexible resistors. Advancements in textile electronics could usher a new generation of smart devices that are entirely flexible. Current systems on cloth primarily use rigid components, which limits the flexibility and comfort of using the fabric devices. To advance this field, I propose a novel method of creating flexible electrical resistors with embroidery. To realize this technology, I created an open-source tool to create embroidery files for machine fabrication. This thesis details the methods and tools created for resistor fabrication. The resistors were tested to …

Thermomechanical Mechanisms That Cause Adhesion Of Aluminum High Pressure Die Castings To The Die, Alex Monroe

Dissertations, Master's Theses and Master's Reports

In high pressure die casting (HPDC) of aluminum, cast material adhering to die is a significant defect. Adhesion occurs in two primary ways. The casting may stick preventing its removal from the die. Aluminum can also adhere to the die and buildup in local areas on the die surface with additional casting cycles. This second form of adhesion is called soldering. Lubricant is the best technology to control all forms of adhesion, but it comes at the cost of casting porosity, blisters, reduced die life, and increased die casting machine wear. New strategies to prevent adhesion are desired to eliminate …

Multiscale Investigation Of Dropwise Condensation On A Smooth Hydrophilic Surface, Shahab Bayani Ahangar

Dissertations, Master's Theses and Master's Reports

The objective of this work is to identify the fundamental mechanism of dropwise condensation on a smooth solid surface by probing the solid-vapor interface during phase-change to evaluate the existence and structure of the thin film and the initial nucleus that develop during condensation. In this work, an automated Surface Plasmon Resonance imaging (SPRi) instrument with the ability to perform imaging in intensity modulation and angular modulation is developed. The SPRi instrument is used to probe (in three dimensions) the adsorbed film that forms on the substrate during dropwise condensation. SPRi with a lateral resolution of ~ 4-10 μm, thickness …

The Effects Of Molybdenum, Chromium, And Niobium On Gray Iron For Brake Rotor Applications, Matthew Hasbrouck

Dissertations, Master's Theses and Master's Reports

Brake rotor composition and microstructure must be optimized for thermal and mechanical performance to avoid thermal-mechanical cracking, excessive wear, and to reduce noise. Niobium is an element that increases the strength and wear resistance of gray iron; however, the interaction of niobium with other common alloying elements (chromium and molybdenum) is not well understood. Thirteen gray cast iron alloys were produced with varying levels of carbon equivalent (CE), Cr, Mo, and Nb. Bars with four different diameters (8, 14, 22, and 30 mm) were cast from each alloy and microstructural and physical properties such as graphite flake morphology, pearlite spacing, …

Development Of A Method To Model An Enclosed, Coaxial Carbon Nanotube Speaker With Experimental Validation, Suraj Prabhu

Dissertations, Master's Theses and Master's Reports

Carbon nanotube (CNT) speakers operate on heat as compared to conventional loudspeakers that operate on vibration. CNT speakers are extremely lightweight, stretchable, flexible, and have high operating temperatures. Due to these advantages, CNT speakers are being considered as a viable replacement option for conventional loudspeakers. One such application is automotive exhaust noise control. The goal of this research is to design an enclosed, coaxial CNT speaker and to develop a modeling method to model this speaker using COMSOL Multiphysics.

As part of this research, an enclosed, coaxial CNT speaker was designed and manufactured for automotive exhaust noise control. The first …

Development And Validation Of Dynamic Programming Algorithm For Eco Approach And Departure, Vasu Goyal

Dissertations, Master's Theses and Master's Reports

Eco Approach and Departure (Eco-AnD) is a Connected and Automated Vehicle (CAV) technology developed to reduce energy for crossing a signalized intersection or set of intersections in a corridor that features vehicle to infrastructure (V2I) communication capability. Eco-AnD technology uses the information of the signal phase and timings (SPaT) received from the V2I communication to optimize the vehicle’s speed profile and produce an energy-efficient maneuver to cross the intersection.

The Eco-AnD algorithm is devised for two vehicles (GM-Volt Gen II & GM-Bolt), both with different powertrain architectures but capable of working in electric-only mode. In simulations, the developed algorithm showed …

Design And Implementation Of An Oxidation Catalyst For A Spark Ignited Two Stroke Snowmobile Engine, Noah Squires

Dissertations, Master's Theses and Master's Reports

Spark ignited two stroke engines are under increasing pressure as emissions standards become stricter, making them a perfect candidate for a catalytic aftertreatment system. Yet several significant challenges to catalysis exist. Namely two stroke exhaust systems are very sensitive to back pressure changes and high emissions concentrations can make controlling the temperature of the catalytic reaction difficult. Therefore, it is imperative that a two stroke specific catalyst design process be developed. This project focused on beginning to develop such a design process. Key results of this work include finding a location for the catalyst in the exhaust system that offers …

Atomistic Monte Carlo Simulation Study Of Phase Transitions In Metal Alloys, Xiaoxu Guo

Dissertations, Master's Theses and Master's Reports

The atomic-scale Monte Carlo simulation study focuses on the intrinsic behaviors of a defect-free crystal that undergoes a cubic-to-tetragonal martensitic transformation. The quasi-spin variable associated with the lattice sites characterizes the local unit cells of the orientation variants of the ground-state martensite phase, which interact with each other through long-range elastic interactions. It is shown that the diffuse scattering in the premartensitic austenite state results from the spatial correlation of the atomic-scale heterogeneous lattice displacements and manifests the displacement short-range ordering. The effects of temperature, elastic anisotropy, and shear modulus softening on the diffuse scattering and displacement short-range ordering are …

Analyzing Variation In Dispersoid Formation In Aluminum Alloys By Minor Changes In Homogenization Temperature, Brendan Treanore

Dissertations, Master's Theses and Master's Reports

The homogenization of billets in the aluminum extrusion industry is a critical step that removes chemical segregation from casting, dissolves low melting point phases, forms nanoscale dispersoid phases, and promotes the beta to alpha transformation of iron particles in the matrix. With ever increasing use of aluminum extrusion in the automotive industry there is a constant need for increased efficiency and consistency in processing of extruded aluminum. The work in this thesis explores the effects of 10°C differences in the homogenization temperature on the formation of dispersoids in 6082 alloys used in the automotive industry. The role of dispersoids is …

Atomistic Continuum Simulations For Nano-Indentation And Compression Of Multi-Layer Graphene, Ashwini Nikumbh

Dissertations, Master's Theses and Master's Reports

Graphene has attracted a great share of research interest due to its extraordinary electrical, thermal, mechanical, and physical properties. Such spectacular properties of graphene open a wide range potential of applications in electronics, energy storage, composites, and biomedical fields. The mechanical properties of graphene can have a huge impact on its performance in graphene-based devices and thus it is important to study them. But the difficulties in experimental characterization and computational limitations to simulate large graphene sample consisting of billions of atoms makes it a challenging task. Thus, accurate and efficient simulation tools to predict the complex deformation of large …

Analytical Assessment Of Project Complexity: A Guide To Managing Projects Through Reduction Of Complexity, Christopher Vanarsdale

Dissertations, Master's Theses and Master's Reports

This research discusses the characteristics that make projects difficult to manage. Project inefficiencies and failures can be attributed to the structure of a system. Developing a measurement for complexity based on the number and nature of interactions in the system can allow project complexity to be reduced while still meeting project objectives. Previous research has identified characteristics or markers of complex systems but does not address how to measure or how to reduce a system’s complexity.

The objective of this dissertation is to develop a metric for complexity that assists project and emergency managers in reducing project complexity either by …

Predicting The Impacts Of Climate Change On The Great Lakes Water Levels Using A Fully Coupled 3d Regional Modeling System, Miraj Kayastha

Dissertations, Master's Theses and Master's Reports

The Great Lakes of North America are the largest surface freshwater system in the world and many ecosystems, industries, and coastal processes are sensitive to the changes in their water levels. The recent changes in the Great Lakes climate and water levels have particularly highlighted the importance of water level prediction. The water levels of the Great Lakes are primarily governed by the net basin supplies (NBS) of each lake which are the sum of over-lake precipitation and basin runoff minus lake evaporation. Recent studies have utilized Regional Climate Models (RCMs) with a fully coupled one-dimensional (1D) lake model to …

A Combustion Model For Multi-Component Fuels Based On Relative Reactivity And Molecular Structure, Arash Jamali

Dissertations, Master's Theses and Master's Reports

A reliable multi-component surrogate fuel model needs to be able to represent both physical properties and chemical kinetics of a real fuel. However, enhancing the fidelity of a model with detailed description of physical and chemical behavior of all fuel components found in real fuels is limited by the prohibitive computational load to calculate the combustion chemistry of the fuel. Hence, it is desirable to achieve computational efficiency by reducing the number of chemical surrogates at the minimum expense of prediction accuracy. The objective of this work is to develop a model that can simulate the oxidation of multi-component fuels …

Development Of The Carbon Nanotube Thermoacoustic Loudspeaker, Troy Bouman

Dissertations, Master's Theses and Master's Reports

Traditional speakers make sound by attaching a coil to a cone and moving that coil back and forth in a magnetic field (aka moving coil loudspeakers). The physics behind how to generate sound via this velocity boundary condition has largely been unchanged for over a hundred years. Interestingly, around the time moving coil loudspeakers were first investigated the idea of using heat to generate sound was also known. These thermoacoustic speakers heat and cool a thin material at acoustic frequencies to generate the pressure wave (i.e. they use a thermal boundary condition). Unfortunately, when the thermoacoustic principle was initially discovered …

Multi-Level Analysis Of Atomic Layer Deposition Barrier Coatings On Additively Manufactured Plastics For High Vacuum Applications, Nupur Bihari

Dissertations, Master's Theses and Master's Reports

While hardware innovations in micro/nano electronics and photonics are heavily patented, the rise of the open-source movement has significantly shifted focus to the importance of obtaining low-cost, functional and easily modifiable research equipment. This thesis provides a foundation of open source development of equipment to aid in the micro/nano electronics and photonics fields.

First, the massive acceptance of the open source Arduino microcontroller has aided in the development of control systems with a wide variety of uses. Here it is used for the development of an open-source dual axis gimbal system. This system is used to characterize optoelectronic properties of …

Case Study Of Gravity-Fed Mountain Spring Tap System In Ha Leronti, Lesotho, Africa, Sarah Peterson

Dissertations, Master's Theses and Master's Reports

Water security has been declining rapidly in Lesotho, Africa in recent years. Lack of water has led to food insecurity, livestock deaths, and the spread of disease. Rural Basotho depend on rainfall to sustain their livelihoods; however, precipitation variability has recently increased due to climate change. For those who reside in the highlands of Lesotho, mountain springs can be a clean source of water. The tap system in the village of Ha Leronti relies on gravity to distribute water from two mountain springs to the ten village taps and nearby school campus. However, it is incapable of transporting the basic …

Design And Testing Of An Open Source Vacuum Oven For Research, Community Recycling, And Additive Manufacturing, Benjamin R. Hubbard

Dissertations, Master's Theses and Master's Reports

To aid the continuing growth of open source tools in the research community, this thesis presents two broadly useful instruments which can be built and operated for a fraction of the cost of equivalent or inferior commercial products. The first device is a digitally-replicable scale, which provides a single framework for making measurements on the order of milligrams all the way up to tens of kilograms by supporting multiple types of load cells. The second device is a vacuum oven, which is validated using the first. The open source vacuum oven facilitates the dehydration of materials at low temperature, providing …