Nuclear Engineering Commons^™

Initiating Event Analysis Of A Lithium Fluoride Thorium Reactor, Nicholas Charles Geraci

Engineering Management & Systems Engineering Theses & Dissertations

The primary purpose of this study is to perform an Initiating Event Analysis for a Lithium Fluoride Thorium Reactor (LFTR) as the first step of a Probabilistic Safety Assessment (PSA). The major objective of the research is to compile a list of key initiating events capable of resulting in failure of safety systems and release of radioactive material from the LFTR.

Due to the complex interactions between engineering design, component reliability and human reliability, probabilistic safety assessments are most useful when the scope is limited to a single reactor plant. Thus, this thesis will study the LFTR design proposed by …

Identification Of Key Drivers For Municipal Utility Performance, Jasmin Alsaied

Pursuit - The Journal of Undergraduate Research at The University of Tennessee

This report explores the various performance indicators for municipal electric utilities and the greatest impact financial investments can make for improving these indicators. A literature search provided key detail about performing an analysis that would prove useful to utilities. The analysis identifies key performance indicators that allowed for the most prudent of investments. Data mining techniques and statistical analyses were performed on data sets concerning the 51 North Carolina municipal electric utilities to identify several key ratios and performance indicators that have the greatest impact on cost of service, system reliability, and customer satisfaction. Statistical analyses were used to determine …

An Exact Analysis For Four-Order Acousto-Optic Bragg Diffraction Which Incorporates Both Incident Light Angle And Sound Frequency Dependencies, Adeyinka Sunday Ademola

Electrical Engineering Theses

This thesis extends the prior work which produced an exact solution to the four-order acousto-optic (AO) Bragg cell with assumed fixed center frequency and with exact Bragg angle incident light. The extension predicts the model that incorporates the dependencies of both the input angle of light and the sound frequency. Specifically, a generalized 4^th order linear differential equation (DE), is developed from a simultaneous analysis of four coupled AO system of DEs. Through standard methods, the characteristic roots, which requires solving a quartic equation, is produced. Subsequently, a derived system of homogeneous solutions, which absorbs the roots obtained using …

Computer Simulation Of Pore Migration Due To Temperature Gradients In Nuclear Oxide Fuel, Ian Wayne Vance

Graduate Theses and Dissertations

A phase-field simulation model is being presented that captures the thermal-gradient-driven migration of pores in oxide fuel associated with fuel restructuring. The model utilizes a Cahn-Hilliard equation supplemented with an advection term to describe the vapor transport of fuel material through the pore interior due to gradients in vapor pressure. In addition, the model also captures changes in a migrating pores’ morphology. Simulations demonstrate that the model successfully predicts pore migration towards the hottest portion of the fuel, the centerline. The simulations also demonstrate changes in pore shape that are in agreement with previous experimental observations. Initially isotropic pores are …

Numerical Simulation Of Metallic Uranium Sintering, Bruce Berry

Graduate Theses and Dissertations

Conventional ceramic oxide nuclear fuels are limited in their thermal and life-cycle properties. The desire to operate at higher burnups as is required by current utility economics has proven a formidable challenge for oxide fuel designs. Metallic formulations have superior thermal performance but are plagued by volumetric swelling due to fission gas buildup. In this study, we consider a number of specific microstructure configurations that have been experimentally shown to exhibit considerable resistance to porosity loss. Specifically, a void sizing that is bimodally distributed was shown to resist early pore loss and could provide collection sites for fission gas buildup. …

Fast Neutron Detection In Nuclear Material Photofission Assay Using A 15 Mev Linear Electron Accelerator, Matthew Steven Hodges

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this research was to use a 15 MeV (K15 model by Varian) linear electron accelerator (linac) for the photon assay of special nuclear materials (SNM). First, the properties of the photon radiation probe were determined. The stochastic radiation transport code, MCNP5, was used to develop computational models for the linac. The spectral distribution of photons as well as dose rate contour maps of the UNLV accelerator facility were computed for several linac operating configurations. These computational models were validated through comparison with experimental measurements of dose rates.

The linac model was used to simulate the photon interrogation …

Analysis Of The Temporal Response Of Coupled Asymmetrical Zero-Power Subcritical Bare Metal Reactor Systems, Kimberly Lynn Klain

UNLV Theses, Dissertations, Professional Papers, and Capstones

The behavior of symmetrical coupled-core systems has been extensively studied, yet there is a dearth of research on asymmetrical systems due to the increased complexity of the analysis of such systems. In this research, the multipoint kinetics method is applied to asymmetrical zero-power, subcritical, bare metal reactor systems. Existing research on asymmetrical reactor systems assumes symmetry in the neutronic coupling; however, it will be shown that this cannot always be assumed. Deep subcriticality adds another layer of complexity and requires modification of the multipoint kinetics equations to account for the effect of the external neutron source. A modified set of …

Applications Of Elpasolites As A Multimode Radiation Sensor, Amber Lynn Guckes

UNLV Theses, Dissertations, Professional Papers, and Capstones

This study consists of both computational and experimental investigations. The computational results enabled detector design selections and confirmed experimental results. The experimental results determined that the CLYC scintillation detector can be applied as a functional and field-deployable multimode radiation sensor.

The computational study utilized MCNP6 code to investigate the response of CLYC to various incident radiations and to determine the feasibility of its application as a handheld multimode sensor and as a single-scintillator collimated directional detection system. These simulations include:

• Characterization of the response of the CLYC scintillator to gamma-rays and neutrons;

• Study of the isotopic enrichment of …

Experimental And Computational Investigations Of Heat Transfer Systems In Fluoride Salt-Cooled High-Temperature Reactors, Joel T. Hughes

Nuclear Engineering ETDs

Fluoride salt-cooled high-temperature reactors (FHRs) face a number of challenges similar to those faced by other Generation IV advanced reactor concepts. Predicting heat transfer in these systems accurately and reliably is one major challenge. Another is ensuring the safety of these systems during challenging operating conditions across the design basis envelope. Finally, achieving good economics to compete in a modern power generation portfolio is necessary for moving any nuclear power plant concept past the pre-conceptual stage. This dissertation attempts to support, from a thermal-hydraulics research standpoint, the case that the FHR can attain these goals. The dissertation focuses on several …

Structural Evolution Of Tungsten Surface Exposed To Sequential Low-Energy Helium Ion Irradiation And Transient Heat Loading, G Sinclair, J K. Tripathi, P K. Diwakar, M Wirtz, J Linke, A Hassanein

School of Nuclear Engineering Faculty Publications

Structural damage due to high flux particle irradiation can result in significant changes to the thermal strength of the plasma facing component surface (PFC) during off-normal events in a tokamak. Low-energy He+ ion irradiation of tungsten (W), which is currently the leading candidate material for future PFCs, can result in the development of a fiber form nanostructure, known as “fuzz”. In the current study, mirror-finished W foils were exposed to 100 eV He+ ion irradiation at a fluence of 2.6 × 1024 ions m−2 and a temperature of 1200 K. Then, samples were exposed to two different types of …

Effect Of Dual Ion Beam Irradiation (Helium And Deuterium) On Tungsten–Tantalum Alloys Under Fusion Relevant Conditions, Sean Gonderman, J K. Tripathi, T J. Novakowski, T Sizyuk, A Hassanein

School of Nuclear Engineering Faculty Publications

The selection of tungsten (W) as a divertor material in ITER is based on its high melting point, low erosion, and strong mechanical properties. However, continued investigation has shown W to undergo severe morphology changes in fusion-like conditions. Recent literature suggests alloying W with other ductile refractory metals, viz. tantalum (Ta) may resolve some of these issues. These results provide further motivation for investigating W–Ta alloys as a plasma-facing component (PFC) for ITER and future DEMO reactors. Specifically, how these alloy materials respond to simultaneous He+ and D+ ion irradiation, and what is the effect on the surface morphology when …

Remote Handled Disposal Enhancement At The Waste Isolation Pilot Plant, Philip Theisen

Nuclear Engineering ETDs

The Waste Isolation Pilot Plant (WIPP) is a deep underground facility for the disposal of Transuranic Defense Waste located in Southeastern New Mexico. Transuranic (TRU) Waste is defined as any radionuclides with an atomic number greater than that of Uranium, has a half-life greater than 20 years, and activity greater than 100nanocuries. According to the ‘Land Withdrawal Act’ (LWA), WIPP is licensed to dispose of 6.2million cubic feet of waste. TRU waste is categorized into two types: Contact Handled (CH) and Remote Handled (RH). CH waste is any waste that does not have a surface dose rate that exceeds 200mrem …

Simulation Of Dust Grain Charging Under Tokamak Plasma Conditions, Zhuang Liu, Dezhen Wang, Gennady Miloshevsky

School of Nuclear Engineering Faculty Publications

Dust grains in fusion devices may be radioactive, contain toxic substances, and may penetrate into the core plasma resulting in the termination of plasma discharges. Therefore, it is important to study the charging mechanisms of dust grains under tokamak's plasma conditions. In this paper, the charging processes of carbon dust grains in fusion plasmas are investigated using the developed dust simulation (DS) code. The Orbital Motion Limited (OML) theory, which is a common tool when solving dust-charging problems, is used to study the charging of dust grains due to the collection of plasma ions and electrons. The secondary electron emission …

Laser-Induced Breakdown Spectroscopy (Libs) In A Novel Molten Salt Aerosol System, Ammon N. Williams, Supathorn Phongikaroon

Mechanical and Nuclear Engineering Publications

In the pyrochemical separation of used nuclear fuel (UNF), fission product, rare earth, and actinide chlorides accumulate in the molten salt electrolyte over time. Measuring this salt composition in near real-time is advantageous for operational efficiency, material accountability, and nuclear safeguards. Laser-induced breakdown spectroscopy (LIBS) has been proposed and demonstrated as a potential analytical approach for molten LiCl–KCl salts. However, all the studies conducted to date have used a static surface approach which can lead to issues with splashing, low repeatability, and poor sample homogeneity. In this initial study, a novel molten salt aerosol approach has been developed and explored …

Finite Element Analysis Of A Friction Clutch System In An Automatic Transmission, Samuel Cook

Capstone Design Expo Posters

The purpose of this project is to develop a computational solution to the effects of certain variables present inside an automatic transmission, more specifically, the friction clutch system that enables and disables different gear-sets. Afton partnered with the School of Engineering looking for a time-sensitive, computational solution to serve as a valuable comparison to what exists at Afton’s disposal currently. The solution is a finite element analysis (FEA) simulation that transforms a real world device with many nuances and intricacies into a simplified model in a two dimensional test space. The challenge exists in keeping the simplified model accurate to …

3d Printed Ear Canal Model, Ahmad Ali, Rosheena Hairston, Hunter Locks

Capstone Design Expo Posters

A multi-material ear canal model was designed and created from CT scans of an actual patient. This ear canal model serves as a training model for trainees, surgeons and doctors to develop a better understanding of the anatomy and physiology of the ear by physically looking, touching and testing the model. The major task taken was to establish and identify the area of interest provided with the files of medical scans by using 3D Slicer. The files were then converted to a stereolithographic (STL) file where it was able to be edited for smoothing in programs such as Meshmixer or …

Radiotherapy Ergonomic Patient Positioning System, Anthony Briscoe Ii, Joseph Oliva, Yvette Smith, Darius Stuvaints

Capstone Design Expo Posters

External beam radiotherapy is a powerful tool to combat cancer, but requires precise positioning of patients. The standard practice involves patients lying on treatment tables within immobilization equipment. These systems have limited clearance between treatment sources and the patient that can be uncomfortable or claustrophobic for patients. Patients may move when uncomfortable, leading to improper dose delivery, possibly causing painful side effects or further cancers. We present an alternative, open configuration patient positioning solution for more ergonomic setup options with competitive positioning capabilities compared to conventional systems.

Our ergonomic positioning system consists of a seat for patients on a scissor …

Underwater Ant House, Mark Duggan, Zachary Ellis, Zachary Soulier

Capstone Design Expo Posters

The project seeks to design and test and submersible enclosure capable of sustaining oxygen breathing life. A mesh covered in a superhydrophobic coating can both restrain water up to a maximum pressure and retain a direct interface between air and water. Oxygen can transfer over this boundary if there is a sufficient difference in concentrations between the water and air.

Multiple designs have been produced with the intent of testing and demonstrating these theories. 3D printing allowed for quick and customizable production of every component. Enclosures were made for testing the maximum allowable pressure and to fit an oxygen sensor. …

Reducing Noise In Automatic Transmission, Connor Golden-Weathers, Riley Hall, Matthew Bosco, Felix Pyatigorskiy

Capstone Design Expo Posters

The efficiency of an automobile increases as its running torque increases. This is an avenue for improving fuel economy that is actively being pursued. However, transmissions running at higher torques produce an unacceptable amount of noise, vibration, and harshness (NVH). NVH occurs most visibly as a result of the vehicle’s friction clutch behavior. At present, machines capable of testing this behavior exist (MTM machine and LVFA rig) but are very expensive in terms of time, space, and production cost.

The goal of this project is to produce a cost-effective machine in which friction clutch behavior can be analyzed in a …

Media Mixing Apparatus, Nick Colt, Eric Depew, Kurt Thoele, Chris Ward

Capstone Design Expo Posters

The purpose of this project is to reduce the physical exertion and radiological exposure of the maintenance worker by reducing mixing time of water and resin beads when replacing resin beads in a shipboard tank. Presently, a maintenance worker empties ⅓ cubic foot of resin media into a bucket, and fills the bucket with about 1-⅓ gallons of water. Then the water and resin media is mixed with a paddle by hand, until it appears homogeneous, creating a slurry. The slurry is dumped into a funnel after the mixing process and introduced to the system after the discharge valve is …

Unattended Underground Energy Harvesting Sensor, Jeffrey Buck, Tzshay Wade, Jaeton Foxley, Brandon Ruffin

Capstone Design Expo Posters

The team designed an underground energy harvesting sensor that utilizes the ambient energy from its surroundings to provide low power telecommunications to a remote host. The scope of this project is to analyze the feasibility of such system and explore the capabilities of available energy harvesting techniques that utilize the environment, feasibility of operation, and creating a design. Some of the most common methods that have been proven to function on certain environments are thermoelectric and solar energy. Thermoelectricity uses a temperature gradient and solar uses the energy of the sun. To provide a remote vibration signal an accelerometer was …

Explosion Damping Device (Blast Shield), Cullen Bade, Juwan Cephas, Raymond Long

Capstone Design Expo Posters

The proposed device has the main goal to protect a vehicle and personal inside the vehicle in the event of an explosion from underneath of a Humvee most likely caused by an IED explosion. The constraints were that the vehicle could not be lifted too far off the ground to increase the chance the vehicle rollover; the design should not block accessibility to the passengers; be versatile in order to help fit different model vehicles; and most important be able to help in deflecting the blast away from the vehicle. The final design consisted on a V-shaped blast shield similar …

3d Printed Sports Mouthguard, Abdullah Mohsen, Abdulrahman Alharshani

Capstone Design Expo Posters

The 3D printed sports mouthguard can be specifically designed to provide exceptional protection and comfort to athletes in any sport. The process by which an athlete undergoes for obtaining their mouthguard requires a substantial amount of time and cost. Introducing 3D printer capabilities into the dental and sporting fields would elicit faster manufacturing time with more economically priced materials.

In testing our theory, the initial components of the research consisted of scanning a dental impression cast and transferring the S.T.L. file scan onto the C.A.D. software. The next important step required us to discover which material to wire with the …

Anthem Sustainability Project, James Askegren, David Coleman, Luis Morgan

Capstone Design Expo Posters

Data centers are multiplying in number and size as electronic business, communication, collaboration, and recreation continue to increase in popularity. A large amount of electrical power consumed by data center computing equipment is converted to heat, requiring dedicated cooling systems 24 hours a day. Some data center operators have begun taking advantage of this heat instead of expelling it to the atmosphere. This approach not only reduces the electricity costs of these facilities but also minimizes the environmental impact they generate. Anthem has a 2.5 MW data center for which they would like to develop an air-to-air thermal recycle method. …

Iec Fusor Mobile Shielding Unit, Dominic Balducci, John Lawson, Bryce Mcdaniels, Robert Rodi, William Simmons

Capstone Design Expo Posters

The VCU Inertial Electrostatic Confinement (IEC) Fusor Senior Design Project provides Virginia Commonwealth University (VCU) with a mobile fusor complete with the necessary shielding to protect operators as well as the general public from potentially hazardous radiation. The VCU IEC fusor is a Farnsworth-Hirsch type reactor, and consists of five basic components; a high voltage power supply, vacuum system, gas regulation system, primary reactor vessel assembly, and radiation shielding. These components were serviced and reassembled on a customized mobile cart. In addition to these components, a specimen holder and viewing monitor were added to the design. The specimen holder provides …

Formula Sae Intake System, Esa Mahmood, Arman Sarwar, Michael R. Smith

Capstone Design Expo Posters

The Formula SAE Intake System is intended to optimize the airflow into a restricted 600cc engine. The intake system is designed, fabricated, and installed in accordance with the FSAE rule book with a focus on maximizing the vehicle’s acceleration. It is directly responsible for determining the drivability of the car and how much horsepower the flow restricted engine produces.

Design of the intake was conceptualized based on researching a number of factors including venturi diffusion angles, plenum volumes, and runner lengths. Initial tests were performed utilizing computational fluid dynamics for a total of 367 flow simulations and 261 running hours …

Design And Prototype Of Next Generation Nascar Brake Caliper, Jesse Crowder, John Knighton, Lenny Ports, Miranda Snyder

Capstone Design Expo Posters

Efficient braking is pivotal to the success of a NASCAR team. Braking occurs when the brake pedal is depressed, causing hydraulic pressure within the caliper housing and on the pistons, which forces the pistons to push the brake pads against the rotors reducing the vehicle’s speed due to the high friction between the pads and rotors. High performance brake calipers are arguably one of the most crucial components of a race car braking system. Short track brake calipers were designed to efficiently decelerate vehicles traveling upwards of one-hundred twenty miles per hour. This is an essential function of vehicles on …

Enhanced Dynamometer For Conducting Long-Term Brake Wear Testing, Grant Adams, Andres Alvarez Del Piño, Casey Greenstreet, Matthew Wall

Capstone Design Expo Posters

The purpose of this project is to develop an automated control system for two constant torque dynamometers Krauss Friction Tester Type RWS60A – Serial no. 080 built in Orangeburg, West Germany recently obtained by FDP Friction Science. This control system will be efficient, effective, safer, and meet the standards of modern day technologies. Currently, the machines are outdated, obsolete, and unable to operate. Therefore, to bring the dynamometers back into full operation and be competitive in today’s industry a new control system that meets industry expectations must be implemented. For this reason, a programmable logic controller from Automationdirect named ClickPLC …

Alternative Method For Posterior Lumbar Discectomy And Development Of Associated Bench Top Test, Alfred Levinson, Parth Patel, Rahul Peddi, Sarah Peters, Jon Willard

Capstone Design Expo Posters

A discectomy is a common surgical procedure performed to remove the fibrous disc material between adjacent vertebrae in the spine, known as vertebral disc. Current methods and tools used in discectomies are time consuming and potentially dangerous, with opportunity for human error. There is a need for a new method of disc removal that can improve clinical results by reducing surgical times, preventing damage to surrounding anatomy, and more thoroughly removing the vertebral disc. A reduction in surgery times and increase of effective disc removal will help to increase success, recovery, and spinal fusion rates. This project aims to provide …

Automated Din Rail Cut And Punch Machine, Youssif Alkheder, Gaston Charreun, Derrian Flemings, Jonathan Liss

Capstone Design Expo Posters

Our project’s main goal is to optimize the process of punching and cutting DIN rail in a manufacturing setting. The current method for cutting and punching DIN rails is tedious and simply too time consuming. An operator is needed to manually load the DIN rail into the cutter, measure the required length and activate the cutter. While this simple process may not take too long at first glance, companies, like Weidmuller, must be able to produce large-quantity orders to successfully meet the demands of their customers. By turning to automation, we are effectively reducing the amount of time it takes …