Mechanical Engineering Commons^™

Development Of Hydrodynamic Channel Routing Model Of The Lower Rio Grande River To Assist In Flood And Stormwater Management, Andrew W. Leeper

Theses and Dissertations - UTB/UTPA

Flooding and stormwater management of the Lower Rio Grande River (LRG) has become a major issue throughout the years with local entities along the river. The purpose of this study is to develop a hydrodynamic channel routing model to predict water surface elevation changes due to flooding. The study area consists of the LRG from Los Ebanos to Brownsville, Texas. This hydrodynamic model displays the hydraulics of the water flow through the LRG and determines where potential flood hazards exist. To verify the accuracy of the model a series of calculated output hydrographs were established at the Progreso Bridge and …

Development Of A Controllable Polymer System Using Interpenetrating Networks, Emilie Bobo

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

My research partners and I have studied the possibility of building a material system with controllable properties using two interpenetrating polymer networks (IPNs). This study is part of a project to build a rapid prototyping system that allows for the printing of objects with predefined spatial distribution of properties, with the goal that property distributions are controlled though interactions at the molecular level.

One can change the properties of an IPN by adjusting the ratio of interpenetrating networks present in a given cured mixture. This is similar to how one obtains different shades of the color green by gradually changing …

Design Of A Compliant Underactuated Robotic Finger With Coordinated Stiffness, Etienne Dessauw

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

The concept of underactuation has been previously developed in the robotic field for grasping applications. For these anthropomorphic grippers, the minimization of the number of input signals, or in other words underactuation, is the most expected characteristic. This method has become very popular in recent decades. Indeed, by minimizing the number of input signals, it minimizes the complexity of the system’s control and at the same time avoids increased weight and cost. The inconvenience of such a technique is that the design of this type of system remains a difficult task if the behavior of the underactuated set of joints …

Numerical Simulation Of Separated And Secondary Flows In Diffusing S-Ducts For Air Breathing Propulsion, Colin James Fiola

All Theses and Dissertations (ETDs)

No abstract provided.

Nutrient And Carbon-Dioxide Requirements For Large-Scale Microalgae Biofuel Production, Benjamin K. Shurtz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Ever-increasing fuel prices and a limited supply of oil worldwide are threatening our economy and way of life in both the near and distant future. In order to reduce oil
dependence, the US Department of Energy (DOE) has established a goal that by the year 2030, 30% of the US transportation fuel will be renewable. The goal equates to
approximately 60 billion gallons per year of renewable fuel.

In an effort to reach the DOE renewable fuel goal, numerous types of plants are being studied, whose oil can be harvested and refined to serve as replacement fuel.
Among the various …

Linear Covariance Analysis For Gimbaled Pointing Systems, Randall S. Christensen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Linear covariance analysis has been utilized in a wide variety of applications. Historically, the theory has made significant contributions to navigation system design and analysis. More recently, the theory has been extended to capture the combined effect of navigation errors and closed-loop control on the performance of the system. These advancements have made possible rapid analysis and comprehensive trade studies of complicated systems ranging from autonomous rendezvous to vehicle ascent trajectory analysis. Comprehensive trade studies are also needed in the area of gimbaled pointing systems where the information needs are different from previous applications. It is therefore the objective of …

Material Characterization Of Nitinol Wires For The Design Of Actuation Systems, Sean P. Kennedy

Master's Theses

A series of tests were performed on nickel-titanium alloy wire, also known as nitinol, to determine the plausibility of designing an actuator using this wire as the method of actuation. These tests have been designed to fully characterize how the wire behaves under steady state and transient conditions allowing for a specific wire selection to be made given known actuator specifications which will result in an efficient design. The wire transient data can be used to design a controller which reduces the actuation time. The research done for the overall project covers a wide scope including wire hysteresis, nitinol transition …

The Next Step Toward Widespread Residential Deep Energy Retrofits, Florida Solar Energy Center, Janet Mcilvaine

FSEC Energy Research Center®

The Building America Partnership for Improved Residential Construction (BA-PIRC) has been working with affordable housing entities to identify cost-effective technical pathways to achieve energy savings levels of 30% and safeguard or enhance indoor air quality (IAQ), durability, and comfort (McIlvaine et al. 2012; Fairey and Parker 2012).

A Characterization Of The Knee Moment Using The Niagara Foot, Kerron James

Mechanical Engineering Theses

A variety of low cost prosthetic feet exist, but sufficient data on these kinds of feet is limited. This study evaluated the effects of the Niagara Foot™ on an amputee performing walking tasks. Specifically, the study determined the effects of this foot on the amputee's residual knee compared to the amputees current prosthetic foot. An active transtibial amputee was used to perform walking tasks across a force plate to collect ground reaction forces of the amputee while wearing the Niagara Foot and the Ottobock® 1C31+ Trias. Motion capture was used to record the amputee's movements in the room. The data …

Computer Vision Based, Non-Contacting Deformation And Shape Measurements: A Revolution In Progress, Michael A. Sutton

Journal of the South Carolina Academy of Science

The rapid expansion of computer technology in the past thirty years has impacted society in innumerable ways. Of interest for this discussion is the breath-taking change in measurement sciences that has occurred as the digital age dawned and has now become part of our daily lives. In particular, the effect on image-based, non-contacting measurements will be described and the continuing revolutionary impact that the resulting technology has engendered will be reviewed. Additionally, the unprecedented expansion of capabilities will be highlighted by presenting a set of illustrative example studies.

Hybrid System For Enhancing Algal Growth Using Vertical Membranes, David J. Bayless, Ben J. Stuart

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A method for enhancing gas-to-liquid transfer rate and algal growth using vertical membranes suspended over a pond, wherein the membranes are formed of fibers. An aqueous solution is applied to the top edges of the membranes through a series of headers. The membranes are exposed to a stream of gas containing soluble gas species as the aqueous solution migrates downwardly through the membranes by virtue of gravity-assisted capillary action. The aqueous solution collects the soluble gases from the gas stream, thus promoting the growth of photosynthetic organisms on the membranes and in the pond. The membranes facilitate a gradual introduction …

The Effect Of Cooling Rate Of Friction Stir Welded High Strength Low Alloy Steel, Scott Anthony Rose

Theses and Dissertations

The friction stir welding of steel has produced a hard zone in several different alloys. Despite its detrimental effects on weld toughness, the reasons behind neither its formation nor a method of reducing its size or effects have been explored. Recent advances in process control allow for direct heat input control, which combined with the use of backing plates of different thermal conductivity allows for an expansion of the process window. These control methods also affect the HAZ cooling rate by providing greater range (a 60% increase compared to a fixed backing plate) and control (five welds within 16 °C/s). …

Popup Height And The Dynamics Of Rising Buoyant Spheres, Randy H. Munns

Theses and Dissertations

In this paper the popup height of rising buoyant spheres is studied over a range of distinct release depths along with the accompanying velocities and accelerations near the free surface. In the past, regimes of motion due to vortex induced vibrations have been classified based on trajectories below the free surface. This study focuses on the popup height, velocity and acceleration at free surface exit, and vortex shedding in order to further define regimes of motion experienced by a rising buoyant sphere. Varying the release depth below the free surface reveals varying exit angles, velocities, accelerations, and popup heights at …

A Comparative Analysis Of Energy Modelingmethods For Commercial Buildings, Spencer Mark Salmon

Theses and Dissertations

This thesis researched the accuracy of measured energy data in comparison to estimated hand calculation data and estimated building energy performance simulation data. In the facility management industry, there is minimal evidence that building energy performance software is being used as a benchmark against measured energy usage within a building. Research was conducted to find examples of measured energy data compared to simulated data. The study examined the accuracy of a simulation software and hand calculations to measured energy data. Data suggests that comparisons may be made between building energy performance simulated data and measured data, though comparisons are solely …

Unveiling The Roles Of Binder In The Mechanical Integrity Of Electrodes For Lithium-Ion Batteries, Jianchao Chen, Jianyong Liu, Yue Qi, Tao Sun, Xiaodong Li

Faculty Publications

In lithium-ion secondary batteries research, binders have received the least attention, although the electrochemical performance of Li-ion batteries such as specific capacity and cycle life cannot be achieved if the adhesion strengths between electrode particles and between electrode films and current collectors are insufficient to endure charge-discharge cycling. In this paper, the roles of binders in the mechanical integrity of electrodes for lithium-ion batteries were studied by coupled microscratch and digital image correlation (DIC) techniques. A microscratch based composite model was developed to decouple the carbon particle/particle cohesion strength from the electrode-film/copper-current-collector adhesion strength. The dependences of microscratch coefficient of …

Variable Fidelity Optimization With Hardware-In-The-Loop For Flapping Flight, Michael Luke Duffield

Theses and Dissertations

Hardware-in-the-loop (HIL) modeling is a powerful way of modeling complicated systems. However, some hardware is expensive to use in terms of time or mechanical wear. In cases like these, optimizing using the hardware can be prohibitively expensive because of the number of calls to the hardware that are needed. Variable fidelity optimization can help overcome these problems. Variable fidelity optimization uses less expensive surrogates to optimize an expensive system while calling it fewer times. The surrogates are usually created from performing a design of experiments on the expensive model and fitting a surface to the results. However, some systems are …

The Sustainability Of Lean Manufacturing As A Competitive Advantage, Louis G. Jones

Theses and Dissertations

Since the early 1990s lean manufacturing has been employed by companies looking to reduce costs, increase efficiencies and improve quality. Academic studies of the financial benefits of lean manufacturing are mixed in their results, where some show benefit and others do not. The objective of the current work was to confirm a financial benefit of lean manufacturing, while also establishing whether such a financial advantage was sustainable. Financial data was collected for a large number of companies in the manufacturing sector, over the period from 1990 to 2010. The data were used to show correlation between inventory turns and return …

Method And Apparatus For Characterizing Microscale Formability Of Thin Sheet Materials, Nasr A. Shuaib, Marwan K. Khraisheh

Mechanical Engineering Faculty Patents

A method of predicting sheet formability at a microscale level includes the steps of providing a grid pattern on a test sheet, bulging the test sheet to a hemispherical shape until a crack is initiated on the surface of the test sheet, detecting the initiation of the crack, acquiring two images of the surface adjacent to the crack and calculating surface strains on the test sheet.

The Water Entry Of Slender Axisymmetric Bodies: Forces, Trajectories And Acoustics, Kyle Gordon Bodily

Theses and Dissertations

Free surface water entry of various objects has been studied using high-speed images and image processing techniques for decades. This thesis studies the forces, velocities, and trajectories of slender axisymmetric projectiles using an embedded inertial measurement unit (IMU). Three nose shapes (cone, ogive, and flat) were used in the study. Additionally, the projectiles were tested at vertical and oblique impact angles with different surface conditions. One-half of each projectile was coated down the centerline with a hydrophobic spray, creating a half hydrophobic, half hydrophilic case. The trajectory of this half-and-half case impacting vertically was compared to the trajectory of symmetrically …

Dynamics And Control Of Wrist And Forearm Movements, Allan W. Peaden

Theses and Dissertations

Wrist and forearm motion is governed both by its dynamics and the control strategies employed by the neuromuscular system to execute goal oriented movement. Two experiments were conducted to increase our understanding of wrist and forearm motion. The first experiment involved 10 healthy subjects executing planned movements to targets involving all three degrees of freedom (DOF) of the wrist and forearm, namely wrist flexion-extension (FE), wrist radial-ulnar deviation, and forearm pronation-supination (PS). A model of wrist and forearm dynamics was developed, and the recorded movements were fed into the model to analyze the movement torques. This resulted in the following …

A Study Of Action Origami As Systems Of Spherical Mechanisms, Landen A. Bowen

Theses and Dissertations

Origami, the Japanese art of paper folding, has been used previously to inspire engineering solutions for compact, deployable designs. Action origami, the subset of origami dealing with models designed to move, is a previously unexplored area for engineering design solutions that are deployable and have additional motion in the deployed state. A literature review of origami in engineering is performed, resulting in seven key areas of technical origami literature from a wide variety of disciplines. Spherical mechanisms are identified as the method by which most action origami models achieve complicated motion while remaining flat-foldable. The subset of action origami whose …

Capillary Filling Of Large Aspect Ratio Channels With Varying Wall Spacing, Dallin B. Murray

Theses and Dissertations

Quantification and prediction of capillary fluid flow in planar nanochannels is essential to the development of many emerging nanofluidic technologies. Planar nanochannels are typically produced using the standard nanofabrication processes of thermal bonding or sacrificial etching. Both approaches may yield nanochannels that are bowed and/or exhibit non-uniform (i.e. non-planar) wall spacing. These variations in wall spacing affect the transient dynamics of a liquid plug filling the nanochannel, causing deviations from the classical behavior in a parallel-plate channel as described by the Washburn model. Non uniform wall spacing impacts the overall frictional resistance and influences the meniscus curvature. In this thesis, …

Near- And Far-Field Spectroscopic Imaging Investigation Of Resonant Square-Loop Infrared Metasurfaces, J. D'Achangel, E. Tucker, Edward C. Kinzel, E. A. Muller, H. A. Bechtel, M. B. Martin, G. Boreman

Mechanical and Aerospace Engineering Faculty Research & Creative Works

No abstract provided.

Subtalar Joint Instability: Diagnosis And Conservative Treatment, Julie Choisne

Mechanical & Aerospace Engineering Theses & Dissertations

Subtalar instability may be caused by various ligamentous injuries. Combined instability at the ankle and subtalar joint is not adequately diagnosed. Further, isolated subtalar instability is usually misdiagnosed which may lead to long term damage to the joint. Developing a non-invasive and clinically practical tool to diagnose subtalar joint instability would be an important asset. The ability of an ankle brace, a common treatment for hindfoot instability, to promote stability for the subtalar joint was not well established. The purposes of this study were to 1) assess the kinematics of the subtalar, ankle, and hindfoot in the presence of isolated …

Inviscid Analysis Of Extended Formation Flight, James Kless, Michael Aftosmis, Andrew Ning, Marian Nemec

Faculty Publications

Flying airplanes in extended formations, with separation distances of tens of wingspans, significantly improves safety while maintaining most of the fuel savings achieved in close formations. The present study investigates the impact of roll trim and compressibility at a fixed lift coefficient on the benefits of extended formation flight. An Euler solver with adjoint-based mesh refinement combined with a wake propagation model is used to analyze a two-body echelon formation at a separation distance of 30 spans. Two geometries are examined: a simple wing and a wing-body geometry. Energy savings, quantified by both formation drag fraction and span efficiency factor, …

Numerical Simulation Of Convection In Triangular Cavities To Predict Solar Still Performance, Jeremy D. Lefevre, W. Jerry Bowman, Matthew R. Jones

Faculty Publications

To improve modeling of solar still behavior, the convection correlations currently used need to be improved upon. Variations in operating parameters and cover geometries make it difficult to use a single correlation to describe the operation of all solar stills. In this work, three right triangles (representing covers at 15, 30, and 45 deg) were modeled, meshed, and solved to predict the convection heat transfer inside for a variety of operating conditions. For a correlation of the form Nu = C · Raⁿ, it was found that C = 1.1, 0.60, and 0.71, and n = 0.19, 0.24, …

Untitled, Evan Beyers, Jonathan Ogland-Hand

Symposium on Research and Creative Expression (SORCE)

The solar furnace research project at Valparaiso University utilizes a decoupled solar thermal electrolysis process for the production of H2 from water. We are focusing on an iron oxide system, which involves the conversion of magnetite to hematite in a cyclical process. Our experimental study for the iron oxide system confirmed that the electrolytic oxidation and thermal reduction steps of the metal oxide occur in a laboratory scale environment. Unfortunately, some of the Fe+3 products for the magnetite system stays in solution when the electrolysis is done in a strong acid. We needed to develop methods to quantify the fraction …

The First Step In Solar Hydrogen Production: Development Of A Solar Thermal Reactor For The Reduction Of Metal Oxide Particles, Jesse Fosheim, Andrew Schrader

Symposium on Research and Creative Expression (SORCE)

A solar thermal reactor has been designed to experimentally investigate promising paths for reducing metal oxide particles to reduced oxidation states (e.g. Fe2O3 to Fe3O4) utilizing concentrated solar energy. This reactor is windowless and is able to handle internal cavity temperatures in excess of 1700 K. It also has a quasi-continuous feed system that allows the particle residence times to be varied for particles between 0.044 mm and 1 mm in diameter. Furthermore, this reactor utilizes an instrumentation system for the measurement of temperature, particle residence time, particle mass flow rate, and solar flux. In an industrial setting, a large-scale …

Environmental And Economically Conscious Magnesium Production: Solar Thermal Electrolytic Production Of Mg From Mgo, J Fosheim, C Baum, B Borth, B Gruenwald, P Nasserifar, G Vanheeren, R Palumbo, E Beyers, R Diver, S Duncan, P Kissinger, S Nudehi, J Ogland-Hand, L Saks, J Schoer, A Schrader, L Venstom

Symposium on Research and Creative Expression (SORCE)

One method to improve the fuel efficiency of American made vehicles is to reduce vehicle weight by substituting steel components with lighter magnesium (Mg) components. Unfortunately, U.S. produced Mg currently costs approximately $3.31 per kg, over seven times the price of steel. Furthermore, Mg production has a staggering energy and environmental impact, consuming up to 102 kW-hr/kg-Mg of energy and producing 36 kg of CO2/kg-Mg. To reduce the overwhelming economic and environmental impact of Mg, a new solar thermal electrolytic process has been developed for the production of Mg from MgO. Through this process, liquid Mg is produced in a …

A Multi-Scale Approach To A Greater Understanding Of The Behavior Of Heterogeneous Materials Under Dynamic Loading, Andrew J. Van Vooren

Master's Theses (2009 -)

The penetration of granular materials is of interest to a variety of different fields, and is an active area of research. The objective of this project is to gain understanding of the dynamics of a projectile penetrating into a granular material. To do this, experiments were run and a numerical model was created.

A dart gun was used to accelerate an aluminum dart to velocities around 100 m/s, which then impacted a target tank filled with Ottawa sand. The dart flew along a view window, which allowed for a recording of the penetration event using a high speed camera. Pressure …