Nuclear Engineering Commons^™

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 …

Effects Of Roughness On Droplet Apparent Contact Angles On A Fiber, M. M. Amrei, M. Davoudi, G. G. Chase, H. Vahedi Tafreshi

Mechanical and Nuclear Engineering Publications

This paper reports on our investigation of the effects of surface roughness on the equilibrium shape and apparent contact angles of a droplet deposited on a fiber. In particular, the shape of a droplet on a roughened fiber is studied via the energy minimization method implemented in the surface evolver finite element code. Sinusoidal roughness varying in both the longitudinal and radial directions is considered in the simulations to study the effects of surface roughness on the most stable shape of a droplet on a fiber (corresponding a global minimum energy state). It is found that surface roughness delays droplet …

In Defense Of Science—What Would John Do?, Mohamed Gad-El-Hak

Mechanical and Nuclear Engineering Publications

Recent onslaughts on the importance of pure research to our collective well-being are trending. In this essay, I discuss the issues involved and offer a rebuttal. The thoughts are inspired by my mentor, academic sibling, and idol John Leask Lumley.

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 …

Venus Lander Design, Garon Morgan, Brian Rodrigues, Dhruv Sachani, Jason Scott

Capstone Design Expo Posters

The students designed an Entry, Descent, and Landing (EDL) system for a lander to reach the surface of Venus. The students used a combination of 3D modelling and programming to design the EDL within given constraints under specific tolerances. An EDL takes into consideration entry flight dynamics, aeroheating, and landing systems. The EDL was divided into three stages (see below). The separation of stages was designed to address unique challenges found at different points throughout the EDL. The primary objective of the first stage was to minimize the heat associated with the entry velocity to the payload. The second stage …

Measurement Of Impact Forces On Teeth And Jaw When Wearing Sports Mouth Guards, Alghamdi Abdullah, Alnaser Mobarak, Quiroz Ingrid, Serrate Ciro Alcoba, Veizaga Rodrigo

Capstone Design Expo Posters

The objective of this project is to accurately measure the forces the teeth and jaw experience when subjected to impact. For this purpose piezoelectric technology (PVDF), which converts voltage to force and vice versa can be used to measure forces applied to teeth. A PVDF cable is calibrated and used for measuring force along with a control measuring device (PCB Piezotronics). The method involves wrapping the PVDF cable around a 3D home-printed, customized denture. The cable was chosen due to the fact that it allows for adequate fit between mouth guard and denture. Two masses, a baseball and 2 lbs …

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 …