Engineering Commons^™

Development Of Dip-Coated Carbon Fibers For Structural Power Composites And Optimization Of Bus Plates For Passively Propagation Resistant Batteries, David Petrushenko

Theses and Dissertations

Increasing demand for lithium-ion batteries in electric vehicles, portable electronics, and electric aircraft is a driving force for the expansion in new battery architectures to achieve higher gravimetric and volumetric efficiencies. In practice, maximizing energy density can be achieved by introducing state-of-the-art materials to increase the capacity of cells or by reducing the system's mass by incorporating lightweight structural materials. An alternative approach is to develop systems capable of performing multiple functions simultaneously that combine mono-functions of the battery and vehicular structure in a multifunctional component capable of storing electrical energy and providing structural support.

The initial focus of this …

Engineering Electronic Properties Of Random Alloys For Catalytic Applications, Andrew N. Okafor

LSU Doctoral Dissertations

Engineering catalytic materials is a key endeavor in the catalysis science to improve the catalytic activity of existing catalysts for specific applications and reduce the dependence on rare metals and minerals. While alloying, or mixing of metals, has been extensively studied, the focus has conventionally been placed on intermetallic phases or nanostructures such as core-shell particles, which are conceptually described by simple lattice models. This research focuses on understanding the catalytic properties of structurally ordered but compositionally disordered (or random) alloys, which have remained under-explored due to complexity at the atomic scale. Existing research focuses on synthesizing multicomponent alloys and …

Simultaneous Crack & Wave Propagation And Acoustic Emission Signal Modelling Using Peri-Elastodynamic, Md Mushfiqur Rahman Fahim

Theses and Dissertations

This work presents the use of Peri-Elastodynamic, a guided wave simulation method based on meshfree non-local Peridynamics theory. To model simultaneous crack and wave propagation simulation and its application on Acoustic Emission (AE) signal modelling, a new formulation is presented. The field of nondestructive evaluation (NDE) and structural health monitoring (SHM) is slowly embracing the advancement in Machine Learning (ML) / Artificial Intelligence (AI) for better and cost-effective assessment of structures and damage prediction. AI/ML can revolutionize the NDE/SHM field by automating the data collection and analyzing processes. However, the big challenge is that the model needs a sheer amount …

Enhancing Surface Texturing Of Zirconia Toughened Alumina Ceramic Through Optimized Electric Discharge Machining Utilizing The Assistive Electrode Method, Yazan Eyas Tuffaha

Theses and Dissertations

Zirconia toughened alumina (ZTA) is a durable and biocompatible ceramic material commonly used in prosthetic hip implants because of its excellent mechanical properties and wear/corrosion resistance. Surface texturing can improve the lubricity and longevity of hip implant bearing surfaces, but precision machining of ceramic materials such as ZTA is very difficult due to suboptimal surface integrity results of traditional machining techniques. This thesis explores the optimization of machining ZTA using electric discharge machining (EDM) - a process usually reserved for conductive metals - to machine holes into the ceramic to create surface textures. EDM is made possible through the assistive …

A Plug-And-Produce Connectivity Framework For Manufacturing Systems, Theodros Abraham Tarekegne

Theses and Dissertations

The Industrial Internet of Things (IIoT) movement has birthed technologies that enable the fusing of physical and digital environments. However, the extensive number of available options for industrial communication and data formatting has remained a barrier to achieving digital knowledge synonymy in industry. There have been previous attempts to establish standards for industrial connectivity and communication, but legacy machines, as well as custom and non-proprietary devices, still face issues communicating data with other manufacturing equipment. To address these challenges, the Industrial Internet of Things initiative has led to the creation of the Plug and Produce (PnP) concept to facilitate the …

Towards The Induction Welding Of Complex, Curved Thermoplastic Composite Structures, Andrew Cole Cromer

Theses and Dissertations

Recent advancements in the aerospace industry, coupled with the anticipated future significance of air travel, have spurred research aimed at increasing manufacturing production and aircraft flying efficiency by implementing new materials and assembly methods. Advanced air mobility (AAM), a subset of the aerospace industry, is anticipated to become a crucial component of the transportation infrastructure in densely populated regions. To meet the expected demand, there is a need for investigations into novel manufacturing and joining methods. This industry necessitates materials that are lightweight, durable, and amenable to high-rate production. One potential avenue under exploration is the utilization of thermoplastic composites. …

Dynamic Response Evaluation Of Loose Gravelly Soils In Centrifuge Modeling Experiments, Siwadol Dejphumee

Theses and Dissertations

Dynamic behavior of gravelly soil has gained more attention in recent years as several case histories of liquefaction of gravelly soil have been reported. Liquefaction can cause failure of infrastructure, leading to economic damage and loss of life. Gravelly soil has unique characteristics and engineering benefits, providing a prevalent and versatile construction material for various infrastructure projects. Therefore, understanding of the gravelly soil behavior under seismic load is critical for assessing the resilience of infrastructure located in seismically active regions. To date, only a few experimental research studies have focused on the dynamic response of gravelly soil, and these studies …

State Estimation And Prediction Based On Simplified First Principle Model Of Lithium-Ion Batteries In Lebesgue Sampling Framework, Enhui Liu

Theses and Dissertations

State-of-charge (SOC) and remaining-dischargeable-time (RDT) are critical states of Lithium-ion batteries (LIBs). SOC indicates the available charge stored in LIBs compared to the total charge capacity of LIBs, while RDT refers to the remaining dischargeable time that LIBs can support under given loading profiles. Accurate SOC estimation and RDT prediction play important roles in guaranteeing the safe and efficient operation of batteries in real applications.

Taking advantage of high fidelity of simplified first principle (SFP) model of LIBs, this research aims to accurately estimate SOC and predict RDT. Firstly, this research establishes an SFP model to describe the battery internal …

The Study And Development Of Autonomous Scarf Repair For Composite Structures: A Focus On Advanced Air Mobility Vehicles, Stephen Hilton

Theses and Dissertations

“I’m sorry I haven’t been able to truly give you a solution to thermoplastic repair” – Arnt. Director GKN Global Tech Center, 2023

The aerospace industry has a prevalence of composite materials due to their outstanding benefits to the mechanical properties of structures while serving to reduce the overall structure weight. With the development of the Advanced Air Mobility market, there is an anticipated growth in the number of composite structures. Also, with the manufacturing environment of the 21st century, these composite structures are more and more being made using thermoplastic composites that can be recycled at the end of …

A Study Of Direct Sensitivity Method Solving Optimal Control Problems With Single And Multiple Time Grids With An Application In An Experimental Hybrid System, Hainan Wang

Theses and Dissertations

Computational methods for optimal control are important for dealing with bottlenecks in industries. By implementing optimal operation strategies obtained from the computational methods into dynamic systems, objectives such as saving energy, reducing cost, exploiting potential, and improving efficiency can be achieved. Computational methods for optimal control have been used in a broad range of disciplines, including aeronautics and astronautics, oil and chemical engineering, power systems, clean energy, biomedical engineering, economics, and management. Due to the great application value of optimal control, its computational methods have drawn worldwide attention. Direct methods are most effective in computational methods for optimal control. Direct …

Crystal Plasticity Modeling Of Heterogeneous Microstructure Of Additively Manufactured Metals, Md Mahabubur Rohoman

Theses and Dissertations

Additive manufacturing (AM) has emerged as a promising technique in the manufacturing industry for producing complex metal components as it provides shape freedom and simplistic processing chain.

Powder bed fusion is the widely used AM technique that uses laser or electron beam as the energy source to melt the metal powder and deposit it in a layer-by-layer fashion. While doing so, the previously molten layers are constantly are in re-heating and re-cooling processes which end up creating an intricate solidification for the deposited layers. Due to the complexity involved in the thermal cycles for the solidification process, columnar grains develop. …

High-Rate Production Of Thermoplastic Composite Structures For Urban Air Mobility Vehicles Utilizing Fastener-Free Assembly Methods, Robert H. Shumpert

Theses and Dissertations

This study aimed to develop a manufacturing plan for a Thermoplastic fiber-reinforced propeller blade for urban air mobility applications. This propeller blade offer a few unique challenges including the complex geometries of the blade. Another important aspect of the blade is using fusion bonding methods to increase the strength of joints in the product while reducing weight from fasteners and adhesives. This manufacturing process will be validated by producing a physical demonstrator to ascertain the efficacy of the manufacturing techniques used. First, the techniques that will make up the manufacturing plan must be selected. To do this, a review of …

A Holistic Quality Management Model For Optimization Of Quality Assurance In Manufacturing, Devon Blakeney Clark

Theses and Dissertations

Quality Management (QM) is essential in manufacturing to ensure products are consistent and functional every time. Consumers expect high quality products that last, and industries unable to accomplish this are destined to fail. Therefore, product quality has always been at the forefront of manufacturer decision making, though it is normally viewed as a given more than as a goal. This means that businesses want quality because it is needed for their survival, but there has not been consideration for how to incorporate innovation into this essential field. Quality needs to be viewed holistically with regards to all manufacturing factors that …

Enhanced Two-Phase Heat Spreading Enabled By Dropwise Condensation, Kai Luo

Theses and Dissertations

The rapidly increasing power density of electronic systems has raised challenges for thermal management. Efficient heat spreading plays an important role in distributing high-density heat to the large-area heat sink and maintaining the junction temperature below the temperature limit during operation. Vapor chambers, a type of flat heat pipe utilizing two-phase heat transfer and fast travel of vapor flow, can achieve far more efficient two-dimensional heat spreading than most conduction-based thermal ground plane materials. By promoting dropwise condensation in vapor chambers, the thermal performance and scalability can be further improved due to the enhanced condensation heat transfer and unique droplet …

Application Of Machine Learning Techniques And The Unscented Kalman Filter To Real-Time Gas Turbine Clearance Prediction, Donald Earl Floyd

Theses and Dissertations

The growth in renewable energy sources and retirement of large baseload coal-fired power stations has led to an accompanying decrease in reliability and security of the electrical grid. Since renewable energy sources are typically non-dispatchable, this can lead to blackouts and/or brownouts for customers. Heavy duty gas turbine power plants (HDGT) offer a solution to this problem. HDGTs are dispatchable, clean, and offer flexibility in the fuel they consume, but operational limitations must be well understood to fully exploit their benefits.

One of the main operational limitations is the tip clearances in the gas turbine. In many cases, the gas …

On The Use Of Cfd Modeling And Analytic Methods To Describe Pressure Drop In Highly Dense Structured Adsorbents In Gas Separation Processes And Fundamentals Of Adsorption, Ryan Timothy Sanders

Theses and Dissertations

The scope of this work can be divided into two main thrusts on topics found within adsorption. The first, and primary, topic is the use of CFD and analytical modeling to describe the flow of gas through a parallel, structured adsorbent channel which is described in Chapters 1 and 2. Chapter 1 establishes a non-experimental methodology based on using a 3D Navier-Stokes (NS) computational fluid dynamics (CFD) model in lieu of experiments, for developing 1D axial pressure drop correlations for structured adsorbents with parallel channels. Chapter 2 utilizes the methodology established in Chapter 1 in order to develop a new …

A Click Chemistry Amplified Nanopore Assay For High Performance Testing Of Protein Biomarkers In Diseases, Xiaoqin Wang

Theses and Dissertations

Nanopore detection technology enables nanometer-scale single-molecule detection, yielding valuable insights into analyte molecules' properties such as size, shape, charge, and concentration. Due to its label-free nature, high sensitivity, and real-time capabilities, it finds widespread application in genomics, proteomics, drug discovery, and environmental monitoring. Click chemistry, encompassing the attachment of a probe or substrate to a biomolecule, termed bioconjugation, features the copper-catalyzed azide-alkyne cycloaddition as a quintessential reaction, forming a 5-membered heteroatom ring. This study harnesses this reaction to craft single-strand DNA probes for nanopore testing, leveraging copper's catalytic properties for signal amplification. Host-guest reaction, a noncovalent bond between molecules, specifically …

Dual-Phase Membrane Reactor And Calcium Oxide-Based Sorbents For High-Temperature Carbon Capture, Utilization And Storage, Kangkang Zhang

Theses and Dissertations

Greenhouse gases, especially CO2 emissions, are responsible for global warming and the reduction of greenhouse gases is vitally important for the sustainability of our modern society. Currently, the most mature CO₂ capture, utilization and storage (CCUS) technology relies on flue gas “amine washing”, a costly and energy intense process that can negatively impact on the efficiency of existing power plants and the cost of electricity produced. Therefore, developing more efficient and cost-effective CCUS technologies is highly imperative. With the increasing production of natural gas in recent years, direct natural gas conversion into valuable chemicals also becomes more attractive than …

Experimental And Computational Understanding Of Solid Oxide Iron Air Battery Performance, Chaitali Morey

Theses and Dissertations

Long-duration energy storage (LDES) (10+ hours) is considered a key technical solution for a widespread penetration of renewable energy into the utility market. However, the currently available storage technologies are limited to less than 10 hours for cost reasons. The benchmark Li-ion battery technology would be economically prohibitive if the storage time goes beyond 4 hours. Therefore, developing new low-cost LDES-compatible battery technologies is highly desirable. A solid oxide iron air battery (SOIAB) has been developed which consists of a reversible solid oxide cell (RSOC) and energy storage unit (ESU) of an iron bed. This battery is considered a promising …

Coastal And Inland Flooding - From Advanced Hydrodynamics And Data-Driven Modeling To Multi-Variate Coastal Vulnerability Assessment, Ahad Hasan Tanim

Theses and Dissertations

Flood risks in coastal and inland areas have historically been underestimated and underpredicted, resulting in increased flood damage and loss of human life. Flood risk under climate change and sea level rise will disproportionately impact low-wealth and marginalized communities, as they are often located in areas with less flood protection and have limited resources to adapt to the impacts of flooding. The systematic workflow of the life cycle of FRM is frequently disengaged in the current state of flood hazard assessment with system vulnerability assessment. This research aims to improve the life cycle of FRM by incorporating flood observation, monitoring, …

Field Implementation Of A Stereo Vision System For Rnt And Stress Measurements In Cwr, Brittany Stinson

Theses and Dissertations

The use of Continuous Welded Rail (CWR) provides many advantages to the rail industry compared to the alternatively used jointed-track segments. However, one significant disadvantage is the development of thermal stresses longitudinally in the rail, which is not of concern when expansion joints are used. This is due to CWR’s inability to release thermal expansion in the absence of joints. The Rail Neutral Temperature (RNT) is the temperature at which the rail is in a stress-free state. A desired RNT is calculated based on local climate conditions and CWR installation practices are implemented to set the desired RNT at installation. …

Fission Product Thermodynamics, Solubility, And Extraction In Molten Salts And Lead, Richard Lee Fitzhugh

Theses and Dissertations

Chemical behavior of fission products in systems relevant to two major advanced nuclear reactor systems, namely the lead-cooled fast reactor (LFR) and molten-salt reactor (MSR), has been studied with a heavy emphasis on thermodynamics. The behavior of fission products in molten salts is examined from a theoretical perspective, with an emphasis on the standard state used to define the thermodynamic activity. A standard state extrapolated from infinite dilution behavior, which is fairly common practice in electrochemistry, is found to facilitate faster, easier, and simpler analysis while retaining much of the accuracy of the complex Modified Quasichemical Model. Inductively-coupled plasma mass …

Void Formation During Liquid Composite Molding Under Varied Pressure With Mechanical Properties Validation, Neil Russell Thompson

Theses and Dissertations

Composite materials have revolutionized products and how they are manufactured. Most large-scale aerospace companies utilize a carbon fiber pre-impregnated with a resin in conjunction with an autoclave to minimize voids, but it is very expensive and requires a great amount of space. The less expensive alternative to prepreg-autoclave processes is known as Liquid Composite Molding (LCM), in which the resin is brought into a mold via overpressure on the resin supply or by a vacuum in the mold. But this process is more prone to voids due to bubble formation. Voids are a critical issue as common failure modes such …

Quiescent Condensation Heat Transfer On Vertical Cicnt Structured Superhydrophobic Surfaces, Clint Mach Hubbard

Theses and Dissertations

This study experimentally investigates the impact of the subcooling magnitude, the carbon-infiltrated carbon nanotube (CICNT) diameter, the time duration of condensation, and amount of non-condensable gases on the nature of dropwise condensation and condensate removal, and heat flux and heat transfer coefficient measurements. Experiments were conducted in a vacuum chamber on a vertically oriented test CICNT surface. The CICNT diameter was varied between 15-120 nm and the subcooling ranged from 0.5-9 °C. Each test ran for a duration of at least one hour and video was recorded at 20-minute intervals. Three modes of condensation were observed: drop jumping, drop wetting …

Behavior Of Reinforced Lightweight Cellular Concrete Backfill For Mechanically Stabilized Earth Walls With Welded Wire Reinforcements, Cole Max Larsen

Theses and Dissertations

Lightweight cellular concrete (LCC) consists of a mixture of cement, water, and a pre-formed foam. The pre-formed foam entrains a high proportion of air voids into the cement water slurry at the time of casting, decreasing the product's overall weight. LCC is also a viable alternative when low native soil strengths prevent the use of traditional backfill methods through mitigating settlement and increasing strength. Due to these benefits, the use of LCC behind mechanically stabilized earth (MSE) walls is gaining popularity. Despite LCC gaining popularity behind MSE walls, the exact nature of the failure envelope is poorly understood. The pullout …

Catalytic Upcycling Of Waste Plastics By Induction Heating, Bernard Whajah

LSU Doctoral Dissertations

The development of plastics over the past half century has led to rapid technological advances; however, the long-term negative environmental impacts of these materials compel new depolymerization and upcycling strategies. Plastics are indispensable due to their unique physical and chemical properties and affordability, leading to a significant increase in production rates. However, their recycling rates lag far behind their production rates. Polyolefins like LDPE and HDPE, which are common plastics, decompose very slowly in the environment. Converting these plastics into useful products often requires high-temperature pyrolysis, resulting in undesired distributions of products.

To address this challenge, this study focuses on …

Tools For Planning Multi-Axis Vibration Qualification Tests, Marcus Edward Behling

Theses and Dissertations

Vibration qualification testing is necessary to ensure that components will endure vibration-induced damage in flight. Multi-axis tests have shown the potential for improvement over single-axis tests, though they require increased planning. This work focuses on planning three critical aspects of these tests: the amount of operational next assembly to include in the test, the size of shakers to use, and the number of shakers to use. Next assembly selection is studied by varying the amount of next assembly included in the lab test, performing physical tests, and comparing the accuracy of environment reconstruction in each test. In doing so, a …

Zno Based Chemiresistive Sensor For Ammonia Detection, Anna Thomas

Theses and Dissertations

This work aims on the development of nanostructured sensing elements based on ZnO for detecting ammonia, specifically designed for applications in poultry and farm fields. To achieve this objective, we prepared sensing elements, including ZnO, CuO, WO3, NiO, ZnO/CuO, ZnO/WO3, ZnO/NiO, and rGO/ZnO, using the spray pyrolysis technique. Structural, morphological, and compositional analyses were studied using X-ray Diffraction (XRD), Field Emission Microscope (FESEM), and X-ray Photoelectron Spectroscopy (XPS), respectively. The vapour/gas detection studies of fabricated sensing elements were carried out in a home built sensing chamber.

The single oxides, ZnO, CuO, WO3, demonstrated ammonia detection in the range of 5-100 …

Design For Pullout Resistance And Global Stability Of Metallic Reinforcements In Mse Walls With Lightweight Cellular Concrete Backfill, Joshua Curt Peterson

Theses and Dissertations

Lightweight cellular concrete (LCC) is a type of concrete that has reduced density and weight compared to traditional concrete. This is achieved by incorporating a large amount of air- filled cells or voids into the mixture. The resulting material is lighter, yet still possesses considerable strength and durability, making it suitable for a range of construction applications, especially in the case of retaining walls because of its reduced weight. Unlike traditional concrete, which can be extremely heavy and place significant stress on the supporting structure, lightweight cellular concrete reduces the pressure on the retaining wall, helping to prevent deformation and …

Utilization Of Sodium Flame Synthesis For The Formation And Deposition Of Pure Metal Materials For Applications In Additive Manufacturing, Zachariah Wargel

McKelvey School of Engineering Graduate Student Theses & Dissertations

Advanced material classes, such as high temperature alloys, ceramics, and refractory materials have become a key area of focus for expansion in the realm of additive manufacturing. Factors such as high melting points, material homogeneity, and physical properties such as ductility limit the application of popular additive manufacturing methods to these material classes. By utilizing sodium flame synthesis and deposition (SFD) technology, nanoparticle materials can be synthesized via combustion in a laminar co-flow diffusion burner and impacted such that the deposits can be used to manufacture designed components. By using the applicable precursor materials of metal chlorides and elemental sodium …