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Full-Text Articles in Nuclear Engineering

Spatio-Temporal Evolution Of Warm Dense Plasmas: Molecular Dynamics Modeling, Harrison Wenzel, Gennady Miloshevsky Jan 2020

Spatio-Temporal Evolution Of Warm Dense Plasmas: Molecular Dynamics Modeling, Harrison Wenzel, Gennady Miloshevsky

Graduate Research Posters

SPATIO-TEMPORAL EVOLUTION OF WARM DENSE PLASMAS: MOLECULAR

DYNAMICS MODELING Cole Wenzel and Gennady Miloshevsky

Virginia Commonwealth University, Department of Mechanical and Nuclear Engineering, 401

West Main St, Richmond, VA 23284-3015

The exo-atmospheric detonation of nuclear device would be of great impact on the material integrity of orbiting satellites. The spectral energy distribution of high intensity X-ray flux, ~10 28 -10 35 photons/(cm 2 ∙s), originating from a nuclear blast is described by the Planck's blackbody function with the temperature from 0.1 keV to 10 keV. Particular damage would occur to the multi-layered, solar cell panels of satellites. However, the X-ray …


The Potentials Of Faecal Sludge Treatment Using Local Conditioners In Tanzania: A Review, Doglas Benjamin1 Dec 2019

The Potentials Of Faecal Sludge Treatment Using Local Conditioners In Tanzania: A Review, Doglas Benjamin1

Tanzania Journal of Engineering and Technology (TJET)

Worldwide, every day human beings generate millions of tons of Faecal Sludge (FS), which is rich in water, nutrients, energy, and organic compounds. Yet FS is not being managed in a way that permits us to derive value from its reuse, while at the same time, millions of farmers struggle with depleted soils and lack of water. In most of the developing countries, energy for cooking is mainly derived from cutting of trees, either as wood or charcoal. Resource recovery and reuse from FS can create livelihoods, enhance food security, support green economies, reduce waste and contribute to cost recovery …


Nano Fab Lab 63, Brian K. Deemer, Josh Clemons, Nick Brodine, Delaney Fitzsimmons Jun 2019

Nano Fab Lab 63, Brian K. Deemer, Josh Clemons, Nick Brodine, Delaney Fitzsimmons

Mechanical Engineering

Lawrence Livermore National Laboratories (LLNL) has several steps in the production process for ceramic nanofiber tubes that they would like to improve - electrospinning, cutting, rolling, sealing and heat treating. We undertook the challenge to deliver LLNL with a semi-automated process that efficiently integrates the steps of cutting, rolling, and sealing to save time and improve control over end dimensions. In this document, we discuss the technical background of the manufacturing steps currently followed to create nanofiber tubes, identify which steps are incorporated in our prototype and explain how they will interface with one another, define the design requirements, present …


Investigation Of The Coupled Nuclear, Thermal-Hydraulic, And Thermomechanical Response Of A Natural Circulation Research Reactor Under Severe Reactivity-Initiated Accident Transients, Darren G. Talley Mar 2019

Investigation Of The Coupled Nuclear, Thermal-Hydraulic, And Thermomechanical Response Of A Natural Circulation Research Reactor Under Severe Reactivity-Initiated Accident Transients, Darren G. Talley

Mechanical Engineering ETDs

Research reactors play an important role in higher education, scientific research, and medical radioisotope production around the world. It is thus important to ensure the safety of facility workers and the public. This work presents a new reactor transient analysis code, referred to as Razorback, which computes the coupled reactor kinetics, fuel element heat transfer, fuel element thermal expansion and thermal stress, and thermal-hydraulic response of a natural circulation research reactor. The code was developed for the evaluation of large rapid reactivity addition in research reactors, with an initial focus on the Annular Core Research Reactor (ACRR) at Sandia National …


Compositional Analysis Of Cerium And Cesium In Rapid Setting Cement As An Immobilization Agent For Nuclear Waste, Riyadh M. Motny Jan 2019

Compositional Analysis Of Cerium And Cesium In Rapid Setting Cement As An Immobilization Agent For Nuclear Waste, Riyadh M. Motny

Theses and Dissertations

A feasibility of rapid setting cement (RSC) as an agent of immobilization for certain elements such as fission products or radioactive materials was explored. Cerium (Ce) and cesium (Cs) have been selected as a surrogate for U and/or Pu and fission products, respectively, in this study in three phases. In Phase I, RSC was evaluated for physical properties (e.g., porosity, density, pH values, etc.) using two groups methods—the cement powder at different concentrations of Ce (2 – 10 wt%) with deionized water (DIW) and artificial seawater (ASW). The results showed that the final setting time and compressive strength of RSC …


Plenum-To-Plenum Heat Transfer Characteristics Under Natural Circulation In A Scaled-Down Prismatic Modular Reactor, Salman Mohammed Alshehri Jan 2019

Plenum-To-Plenum Heat Transfer Characteristics Under Natural Circulation In A Scaled-Down Prismatic Modular Reactor, Salman Mohammed Alshehri

Doctoral Dissertations

“Gas-cooled reactor (GCR) is being developed under the Next Generation Nuclear Plant Program (NGNP) in nuclear engineering studies. As the world searches for an energy source with high energy density, clean, abundant, and storable nature to avoid global warming issues, GCR seems to be a promising solution, particularly the possibility of producing hydrogen. Studying and developing the safety analysis and GCR technologies are required for the optimum design and safety of GCR system. Multiphase Reactors Engineering and Applications Laboratory (mReal) at Missouri University of Science and Technology (S&T) has developed a natural convection heat transfer test facility with one riser …


Computational Fluid Dynamics Modeling And Comparison Of Advanced Techniques For Heat Transfer Augmentation For Nuclear Applications, Salman Mohammed Alzahrani Jan 2019

Computational Fluid Dynamics Modeling And Comparison Of Advanced Techniques For Heat Transfer Augmentation For Nuclear Applications, Salman Mohammed Alzahrani

Doctoral Dissertations

“Passive safety is the most important feature of NuScale’s reactor designs. Twist tape is one passive heat enhance heat technique. The present research investigated thermo-hydraulic characteristics of natural and forced convection of water under different configurations of twisted tape inserted in tube as well as NuScale rod bundles for uniform wall heat flux using computational fluid dynamics (CFD) using ANSYS Fluent 18.1. Results for twist tape inserted in tube under natural circulation showed that heat transfer enhanced and pressure drop increased to 28% and 102.8% over the plain tube respectively. Regularly spaced tapes, and different widths of the twisted tapes …


Detector Arrays For Nuclear Security And Safeguards Applications, Jessica Hartman May 2018

Detector Arrays For Nuclear Security And Safeguards Applications, Jessica Hartman

UNLV Theses, Dissertations, Professional Papers, and Capstones

Over the last two decades it has become increasingly apparent that there is a need for new technologies capable of reliable and efficient fast neutron detection. As national and international stockpiles of 3He continue to dwindle, the need to find a new gold standard of neutron detection becomes more critical. Moreover, neutrons are generated typically in the MeV energy range. The use of 3He detectors for fast neutron measurements requires the use of moderators. Detector arrays capable of fast neutron detection are one solution to this problem. To this end, the focus of this work was the study of detector …


Experimental Evaluation Of Uranyl Transport Into Mesoporous Silica Gel Using Fluorescence, Brandon M. Dodd Jan 2018

Experimental Evaluation Of Uranyl Transport Into Mesoporous Silica Gel Using Fluorescence, Brandon M. Dodd

Theses and Dissertations

This research investigated parameters that can affect the use of nanoporous silica gel as a media for accumulating a detectable amount of uranium. The unique fluorescence of the Uranyl (UO22+) ion was used to evaluate the transport kinetics and accumulation within silica gel in a static fluid and under pressure driven flow. The addition of fluid flow decreased the time constant from on the order of an hour to approximately 2s with a very low fluid velocity of 0.36cm/s. The 0.36cm/s fluid velocity was found to be the critical velocity above which there was no gain in …


Numerical Simulations Of Transcritical Natural Convection, Ruiwen Wei, Carlo Scalo, Mario Tindaro Migliorino, Kukjin Kim, Jean-Pierre Hickey Aug 2017

Numerical Simulations Of Transcritical Natural Convection, Ruiwen Wei, Carlo Scalo, Mario Tindaro Migliorino, Kukjin Kim, Jean-Pierre Hickey

The Summer Undergraduate Research Fellowship (SURF) Symposium

In modern engineering applications, system overheating is a key issue that needs to be solved with efficient and reliable cooling technologies. Among the possible mechanisms that these are based on, natural convection cooling is one of the most frequently employed, with applications ranging from cooling of computer micro-components to large nuclear reactors. While many studies have been performed on natural convection employing supercritical or subcritical fluids, little attention has been given to fluids in their transcritical regime. The latter has the potential to yield high performances while avoiding detrimental effects of two-phase systems (e.g. cavitation). In the present study, 2D …


Evaluation And Enhancement Of Clean Energy Systems: Analytical, Computational And Experimental Study Of Solar And Nuclear Cycles, Nima Fathi Jul 2017

Evaluation And Enhancement Of Clean Energy Systems: Analytical, Computational And Experimental Study Of Solar And Nuclear Cycles, Nima Fathi

Mechanical Engineering ETDs

Clean (and specifically renewable) energy is steadily improving its global share. However, finite availability of fossil fuels and the growing effects of climate change make it an urgent priority to convince the industry and governments to incentivize investment in the renewable energy field and to make it more attractive by decreasing the capital cost. Until recently, uncertainties in funding limited renewable energy development, especially in the US. That limitation has been one of the barriers to progress. Another limitation of many renewable energy systems is the variability in their output, which makes them unsuitable for baseline power production. Therefore, fossil …


Initiating Event Analysis Of A Lithium Fluoride Thorium Reactor, Nicholas Charles Geraci Jul 2017

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 …


Computer Simulation Of Pore Migration Due To Temperature Gradients In Nuclear Oxide Fuel, Ian Wayne Vance May 2017

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 …


Fast Neutron Detection In Nuclear Material Photofission Assay Using A 15 Mev Linear Electron Accelerator, Matthew Steven Hodges May 2017

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 …


Laser-Induced Breakdown Spectroscopy (Libs) In A Novel Molten Salt Aerosol System, Ammon N. Williams, Supathorn Phongikaroon Jan 2017

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 Jan 2017

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 Jan 2017

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 Jan 2017

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 Jan 2017

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 Jan 2017

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 Jan 2017

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 Jan 2017

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 Jan 2017

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 Jan 2017

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 Jan 2017

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 Jan 2017

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 Jan 2017

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 Jan 2017

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 Jan 2017

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 Jan 2017

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 …