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Articles 1 - 30 of 220
Full-Text Articles in Engineering
Thermodynamic Modeling Of Uranium Nitride With Select Actinides And Fission Products, Eric Reece Mcmanus
Thermodynamic Modeling Of Uranium Nitride With Select Actinides And Fission Products, Eric Reece Mcmanus
Theses and Dissertations
Uranium mononitride fuel is being investigated as a potential nuclear fuel for a Westinghouse lead-cooled fast reactor due to factors such as its high uranium density, high melting point, and favorable thermal conductivity. To obtain an understanding of the thermochemical behavior of UN fission products and minor actinides, thermodynamic data was obtained from various resources to create a database to represent the behavior of the fuel. This database was used to generate an Ellingham diagram to represent the relative thermodynamic stability of the phases over the reactor temperature range. A simulation was run computing the equilibrium state of the fuel, …
The Effect Of Chromium Coatings On Hydrogen Uptake In Zirconium Alloy Nuclear Fuel Cladding, Jorie Lyn Walters
The Effect Of Chromium Coatings On Hydrogen Uptake In Zirconium Alloy Nuclear Fuel Cladding, Jorie Lyn Walters
Theses and Dissertations
The amount of hydrogen in a nuclear reactor can have a profound impact on its performance and safety when it is absorbed into or released from fuel rods. Hydrogen pickup in modern fuel cladding materials has been minimized by alloying additions and microstructural texture engineering, but these materials are still susceptible to hydrogen release during high temperature oxidation. The nuclear accident at the Fukushima Daiichi power plant in 2011 resulted in hydrogen gas production and subsequent explosions which led the United States Department of Energy to initiate a program to develop enhanced nuclear fuel cladding materials. New cladding materials include …
Microchannel Slip Flow Characteristics By Time Travel After Photobleaching Velocimetry, Brandon James Sellers
Microchannel Slip Flow Characteristics By Time Travel After Photobleaching Velocimetry, Brandon James Sellers
Theses and Dissertations
Interfacial science follows the study of observing behavior between two or more phases of matter when in contact. For example, a liquid solution passes through a microchannel, and the walls interact with the fluid shearing along the surface. The fluid particles develop momentum changes from interfacial phenomena and slip along the wall begins to affect the fluid body. Slip flow is a name for the phenomenon, and with it, modeling velocity for the interfacial behavior demands both resolution and minimal interference. Laser-induced fluorescence photobleaching anemometry (LIFPA) works as a sound method for acquiring data on microchannel flow, but it needed …
Crystal Plasticity Modeling Of Heterogeneous Microstructure Of Additively Manufactured Metals, Md Mahabubur Rohoman
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. …
A Plug-And-Produce Connectivity Framework For Manufacturing Systems, Theodros Abraham Tarekegne
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 …
A Holistic Quality Management Model For Optimization Of Quality Assurance In Manufacturing, Devon Blakeney Clark
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 …
Experimental And Computational Understanding Of Solid Oxide Iron Air Battery Performance, Chaitali Morey
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 …
Application Of Machine Learning Techniques And The Unscented Kalman Filter To Real-Time Gas Turbine Clearance Prediction, Donald Earl Floyd
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 …
Wide View And Line Filter For Enhanced Image Gradient Computation And Edge Determination, Luke Bagan
Wide View And Line Filter For Enhanced Image Gradient Computation And Edge Determination, Luke Bagan
Theses and Dissertations
Edge determination is a challenging yet crucial step in the object detection process for images. It is the first in a multi-step process, serving as the foundation for all subsequent operations. Its accuracy directly affects the success of any future processing techniques and final detection. The challenge of edge detection is derived from a variety of factors, including noise, image sharpness, orientation, empirical parameters, and computational complexity. Many traditional kernel-based operators excel at tackling one of these problems, but trade off their ability to handle others. For example, the popular Sobel operator uses a horizontal and vertical constant high-pass kernel. …
Real-Time Edge Computing For Autonomous Systems, Junlin Ou
Real-Time Edge Computing For Autonomous Systems, Junlin Ou
Theses and Dissertations
This research presents systematic studies and algorithmic and hardware development to enable real-time edge computing for autonomous systems, in particular, for robot path planning and localization applications. First, a low-cost, indoor, multi-camera positioning system is proposed to localize ground robots using the ArUco marker. In this system, the normalized coordinates of the marker processed by OpenCV are utilized to calculate the camera coordinates. Data-driven models are developed to establish a mapping relationship between the camera coordinates and the world coordinates of the marker. Fifty data pairs of the camera and world coordinate systems within one camera view (150 pairs in …
Studies Of Damage Tolerance In Automated Fiber Placement Based Heterogeneous Meso-Architectured Carbon/ Epoxy Composite Laminates., Karan Kodagali
Studies Of Damage Tolerance In Automated Fiber Placement Based Heterogeneous Meso-Architectured Carbon/ Epoxy Composite Laminates., Karan Kodagali
Theses and Dissertations
Traditional unidirectional (UD) carbon fiber-reinforced polymer matrix composites manufactured via automated fiber placement (AFP) are widely used in aerospace structures. While heterogeneous at the micro-scale, these materials are homogeneous at the meso-scale (ply-scale). The major limitation is its limited toughness, poor damage tolerance/impact resistance capability and the inability to sufficiently redistribute stresses, resulting in strength-toughness tradeoffs, making them susceptible to impact damage. From previous studies, there is an understanding that fiber architecture has a first order effect on the damage tolerance. Introducing new discontinuous/heterogeneous meso-scale architectures, through an optimal merger of material and structure, can result in unprecedented property improvements …
Material Development And Optimization Of Solid Oxide Cells For Energy Conversion And Storage, Wanhua Wang
Material Development And Optimization Of Solid Oxide Cells For Energy Conversion And Storage, Wanhua Wang
Theses and Dissertations
There has been an increasing interest in clean and renewable energy generation for highlighted energy and environmental concerns. Solid oxide cell (SOC) has been considered as one of the most promising technologies since it can convert chemical energy to electricity in the fuel cell mode and store electricity to chemicals in the electrolysis mode. The present work is devoted to materials development in both oxygen ion conducting SOC (O-SOC) and proton conducting SOC (P-SOC). The objective of this study is to design and optimize the electrolyte and electrode materials for SOC in energy conversion and energy storage applications. One major …
Particle-Free High Spatial Resolution Velocimetry For Slip Flow Detection, Malhar Prasad Joshi
Particle-Free High Spatial Resolution Velocimetry For Slip Flow Detection, Malhar Prasad Joshi
Theses and Dissertations
Microfluidic systems have a wide range of applications, including biomedical devices, lab-on-a-chip technologies, and aerospace propulsion. Understanding and quantifying the slip flow phenomenon in these microscale and nanoscale channels is of paramount importance for precise control and optimization of fluidic processes. Our study presents a novel approach to directly measure the velocities in a microchannel using Laser Induced Fluorescence Photobleaching Anemometer (LIFPA) and Travel Time After Photobleaching Velocimetry (TTAPV). In this experimental study, microchannels with micrometer dimensions were used, and slip flow conditions controlled. The LIFPA-TTAPV approach was applied to measure slip velocities in the near wall regime, providing accurate …
A Globalized Optimization Schema For Automated Fiber Placement Processing Parameters, Matthew John Godbold
A Globalized Optimization Schema For Automated Fiber Placement Processing Parameters, Matthew John Godbold
Theses and Dissertations
Automated Fiber Placement is an advanced manufacturing technique for industrial-scale composite structures. Advanced robotics coupled with composite manufacturing results in faster and more consistent results than previously obtained through hand layup. The complexity and interconnectedness of the automated fiber placement process provides a difficult challenge for traditional modeling techniques. Modeling within automated fiber placement currently utilizes physics-based modeling to inform the translation of a design to a manufacturing plan. The intricacy of the automated fiber placement process dictates that attempts at modeling or optimizing these processes are often limited in their scope. Physics-based modeling for manufacturing typically involves numerous interacting …
Synthesis And Characterization Of Electrode Materials Of Solid Oxide Cells For Energy Conversion And Storage, Haixia Li
Theses and Dissertations
Solid oxide cells (SOCs) can directly convert chemical energy to electricity in the fuel cell mode and store electricity to chemicals in the electrolysis mode. However, there are still critical barriers, such as energy efficiency and durability, for developing and commercializing SOCs. This dissertation aims to design electrode materials and optimize the cell fabrication process to address the critical barriers for SOCs in energy conversion and energy storage applications. Therefore, one primary focus of the dissertation is to develop robust fuel electrode material for solid oxide fuel cells (SOFCs) with improved sulfur tolerance. In addition, the design of novel fuel …
Rapid Prediction Of Phonon Density Of States By Graph Neural Network And High-Throughput Screening Of Candidate Substrates For Wide Bandgap Electronic Cooling, Mohammed Saif Ali Al-Fahdi
Rapid Prediction Of Phonon Density Of States By Graph Neural Network And High-Throughput Screening Of Candidate Substrates For Wide Bandgap Electronic Cooling, Mohammed Saif Ali Al-Fahdi
Theses and Dissertations
Machine learning has demonstrated superior performance in predicting vast materials properties. However, predicting a continuous material property such as phonon density of states (DOS) is more challenging for machine learning due to the inherent issues of data smoothing and sensitivity to peak positions. In this work, phonon DOS of 2,931 inorganic cubic structures with 63 unique elements from the Open Quantum Materials Database are calculated by high precision density functional theory (DFT). With these training data, we build an equivariant graph neural network (GNN) for total phonon DOS of crystalline materials that utilizes site positions and atomic species as input …
Water Quality Monitoring And Mapping Using Rapidly Deployable Sensor Nodes, Mohamed Abdelwahab
Water Quality Monitoring And Mapping Using Rapidly Deployable Sensor Nodes, Mohamed Abdelwahab
Theses and Dissertations
Efficient and continuous monitoring of water quality parameters plays a pivotal role in responding to pollution incidents and ensuring the safety of both human consumption and ecological resources. This research introduces an affordable and dependable in-situ water quality sensor package designed for seamless continuous monitoring, providing essential data to facilitate informed decision-making in water resource management. The sensor package enables comprehensive on-site assessment of key water characteristics, including pH, temperature, turbidity (measured in NTU), and total dissolved solids (TDS, measured in ppm). Spatial interpolation techniques, specifically Kriging, are employed to extrapolate variable values at unobserved locations based on nearby measurements. …
Acoustic-Emission Monitoring Of Lap Joint Fatigue Cracks, Siddharth Kannan
Acoustic-Emission Monitoring Of Lap Joint Fatigue Cracks, Siddharth Kannan
Theses and Dissertations
Structural integrity is a pivotal consideration in the field of engineering applications, and understanding the behavior of materials and joints under various loading conditions is critical. This thesis presents a novel approach to detect and analyze fatigue induced cracks in various test specimens using Piezoelectric Wafer Active Sensors. This approach is widely used in Structural Health Monitoring applications involving acoustic emissions that can be captured using PWAS which in turn gives the surface response to applied stresses. The ultimate goal of the research is to identify the length of a fatigue crack originating from lap joints and to develop a …
Elastic Sensing Skin For Monitoring Of Concrete Structures, Emmanuel Abiodun Ogunniyi
Elastic Sensing Skin For Monitoring Of Concrete Structures, Emmanuel Abiodun Ogunniyi
Theses and Dissertations
Soft elastomeric capacitors (SECs) are emerging as potential low-cost solutions for monitoring cracks and strains in concrete infrastructure, a crucial aspect of structural health monitoring. Effective long-term monitoring of civil infrastructure can reduce the risk of structural failures and potentially reduce the cost and frequency of inspections. However, deploying structural health monitoring (SHM) technologies for bridge monitoring is expensive, especially long-term, due to the density of sensors required to detect, localize, and quantify cracks. Previous research on soft elastomeric capacitors (SEC) has shown their viability for low-cost monitoring of cracks in transportation infrastructure. However, when deployed on concrete for strain …
Liquid Cooling System For A High Power, Medium Frequency, And Medium Voltage Isolated Power Converter, Hooman Taghavi
Liquid Cooling System For A High Power, Medium Frequency, And Medium Voltage Isolated Power Converter, Hooman Taghavi
Theses and Dissertations
Controlling and transforming electrical power from one form into another is the Primary function of the power electronics systems that are employed today. These systems have a wide variety of applications and are utilized in things like industrial automation, electric cars, consumer electronics, and renewable energy systems, among other things. The functioning of power electronics systems results in the production of a substantial quantity of heat, despite the fact that these systems are very dependable and efficient. This heat must be dispersed to preserve system performance and avoid component damage. By ensuring that the working temperature of the components stays …
Automated Fiber Placement Through Thickness Defect Stacking Optimization, Noah Christopher Swingle
Automated Fiber Placement Through Thickness Defect Stacking Optimization, Noah Christopher Swingle
Theses and Dissertations
In its 2022 commercial market outlook, Boeing forecasted an 80% increase in the global fleet through 2041 compared to 2019 pre-pandemic levels. This sharp rise in demand will drive pressure onto airframe manufacturers to ramp up production and find more efficient ways to design and manufacture airplanes. Complicating this challenge is the industry’s recent transformation from traditional metal-based airframes towards hybrid composite-metal aircraft. While composites have been used in aviation for decades, aircraft manufacturers are still struggling to design and manufacture quality parts at a high rate. Automated Fiber Placement (AFP) is one of the main manufacturing techniques used to …
Development Of Atomistic Machine Learning Approaches For Thermal Properties Of Multi-Component Solids And Liquids, Alejandro David Rodriguez
Development Of Atomistic Machine Learning Approaches For Thermal Properties Of Multi-Component Solids And Liquids, Alejandro David Rodriguez
Theses and Dissertations
Currently, heat transfer in many industries is the limiting factor for innovation, especially in the energy sector. For example, maximizing thermal conductivity of ceramic coatings in power plant devices improves the overall electrical to thermal energy ratio, whereas minimizing thermal conductivity is required for desirable heat-to-electricity conversion in thermoelectric devices. As such, rapid discovery of new materials with extreme thermal conductivity values is quintessential for the near-future deployment of current and developing energy applications.
The vibrational properties of crystalline materials are essential for their ability to conduct heat. Fundamentally, the restorative atomic forces of displaced atoms are sufficient to represent …
Gpu-Enabled Genetic Algorithm Optimization And Path Planning Of Robotic Arm For Minimizing Energy Consumption, Yichuan Cao
Gpu-Enabled Genetic Algorithm Optimization And Path Planning Of Robotic Arm For Minimizing Energy Consumption, Yichuan Cao
Theses and Dissertations
The robotic arm represents a complicated mechanical system and advanced engineering principles in robotics, enabling precise and efficient manipulation and interaction with objects in a variety of applications, such as manufacturing, healthcare, space exploration, and other industries. In most cases, energy consumption of robotic tools has been given little consideration due to their perceived insignificance compared to the benefits they offer. However, the increasing capacity demands of factories and the expanding use of robotic arms necessitate careful evaluation and reduction of energy consumption. In this regard, given a task configuration, adjusting the arm's movement path emerges as one of the …
An Artificial Intelligence Approach To Fatigue Crack Length Estimation From Acoustic Emission Signals, Shane T. Ennis
An Artificial Intelligence Approach To Fatigue Crack Length Estimation From Acoustic Emission Signals, Shane T. Ennis
Theses and Dissertations
As in service aircraft begin to age and fatigue, a method for evaluating the operational life they are currently operating under and have remaining comes into question. Structural health monitoring is (SHM) is a popular method of structural analysis with growing interest in the aerospace industry. SHM is capable of damage assessment and structural life estimations.
The ultimate goal of the research presented in this thesis is to develop a methodology of classifying the length of a fatigue crack though the use of machine learning. The thesis has three major chapters as described below.
The first chapter deals with the …
An Autonomous Aerial Drone System For Water Fluorescence Mapping And Targeted Sampling, Kazi Ragib Ishraq Sanim
An Autonomous Aerial Drone System For Water Fluorescence Mapping And Targeted Sampling, Kazi Ragib Ishraq Sanim
Theses and Dissertations
At present, aerial drones, also known as Uncrewed Aircraft Systems (UAS) or Unmanned Aerial Vehicles (UAV), are increasingly used in time and effort-heavy scientific exploration applications. One such application is inspecting the physical, chemical, and biological state of water bodies. This thesis presents a novel autonomous system capable of sensing water properties and collecting up to three 250 mL water samples from multiple sampling locations. The system features a customized aerial drone with an in-house built fluorescence sensor and pumping mechanism. It can also map the gradient of fluorescent content across the body of water to determine the best sampling …
Multidimensional Transport-Coupled Numerical Investigation Of Non-Premixed Low-Temperature Flame In Atmospheric And High-Pressure Systems, Sudipta Saha
Theses and Dissertations
Gas-phase chemical reactions coupled with multidimensional fluid flow and heat and mass transport are found in various applications, i.e., from conventional engine applications to novel combustion techniques. With the goal of understanding such complex coupling in reacting flow systems, this dissertation work focuses on developing multi-physics simulation frameworks to investigate the effect of multidimensional transport on flame dynamics. This study primarily focuses on the modeling and simulation of low temperature flame formation in i) a canonical experimental setting with counterflow burners and ii) a supercritical water medium (i.e., hydrothermal flame).
In the first part of the dissertation, simulations of the …
Development Of System Pressure Drop Calculation Methods For Dilute Phase Pneumatic Conveying, Ross Daniel Gorman
Development Of System Pressure Drop Calculation Methods For Dilute Phase Pneumatic Conveying, Ross Daniel Gorman
Theses and Dissertations
This work is focused on dilute and dense phase pneumatic conveying of bulk solids. The motivation of this work is to use industrial data to scale up existing models for pressure drop in pneumatic conveying systems, determine which models best predict pressure drop in full conveying systems, and find the empirical coefficients that go with these models.
Several major research objectives were accomplished by this work. First, system pressure drop methods were evaluated in this research. Other researchers have focused on single pipe section type pressure drops. Second, the data used in this research both for the machine learning evaluations …
Timing Deterministic Structural Model Updating Considering Impact And Fatigue Damage, Jason Michael Smith Jr.
Timing Deterministic Structural Model Updating Considering Impact And Fatigue Damage, Jason Michael Smith Jr.
Theses and Dissertations
Naval ship structures such as support trusses, hull sections, driving machinery, and load-bearing beams are subjected to various damage states that develop on short-term (i.e. impact) and long-term (i.e. fatigue) timescales. Naval structures fitted with a structural health monitoring system with damage detection abilities will enable appropriate real-time adjustments to the ships’ posture and control policies and thus have increased survivability and lethality. A digital twin can provide real-time condition assessment of naval structures when conjoined with a decision-making framework will increase naval ship survivability through informed response management. A fundamental challenge for the development of digital twins is reliable …
Vision Controlled Autonomous Stakebot For Driving Stakes And Its Digital-Twin, Corey Lee Leydig
Vision Controlled Autonomous Stakebot For Driving Stakes And Its Digital-Twin, Corey Lee Leydig
Theses and Dissertations
In this thesis a novel vision-based AI driven autonomous ‘StakeBot’ is proposed to serve the agricultural 4.0 industries of the future. In recent years supply, demand and production of vegetables that are harvested from plants with weak stems like bell pepper, tomato, eggplant has been significantly up by several fold. With growing demand and new green-house establishments across the country production of vegetables will require a tremendous number of labors which will be hard to supply soon. To overcome the issues in addition to the labor shortages, automation through robotics will be the only viable solution. Plants like bell peppers …
Nondestructive Damage Detection And Stress Corrosion Crack Mitigation In Stainless Steel Plates, Andrew Philip Campbell
Nondestructive Damage Detection And Stress Corrosion Crack Mitigation In Stainless Steel Plates, Andrew Philip Campbell
Theses and Dissertations
The ability to inspect and detect damage within a structure without permanent damage has broad appeal in a range of engineering applications from aerospace structures to nuclear facilities. Non-destructive evaluation (NDE) using guided ultrasonic Lamb waves has growing potential and popularity in these fields. Lamb waves are known for being sensitive to material properties and various defects across the thickness such as cracks in metallic structures and delamination or debonding in composite structures. Research has also been done on the development of fully non-contact system that generates and detects Lamb waves, particularly focused on the use of pulsed laser for …