Nuclear Engineering Commons^™

Tellurium Corrosion Of Type 304/304l Stainless Steel, Iron, Chromium, And Nickel In High-Temperature Liquid Sodium, Yi Xie

Purdue University Libraries Open Access Publishing Fund

Investigating tellurium (Te) corrosion on structural materials is crucial for sodium-cooled fast reactors (SFRs) due to radionuclide presence and knowledge gaps. In this study, Type 304/304L stainless steel (SS304), chromium (Cr), iron (Fe), and nickel (Ni) samples were immersed in low-oxygen environments with Te in liquid sodium at 773 K for 30 days. At 10 ppm oxygen, SS304 showed multiple oxide layers, including a compact NaCrO2 interlayer and porous Na-Fe-Ni-O outer layers. Tellurium penetrated through the porous layers but was hindered by the NaCrO2 interlayer. At 0.01 ppm oxygen, Cr had no oxide layer, while Fe and Ni had unstable …

Corrosion Related To The Nuclear Waste Containers, Ali Ebrahimzadeh Pilehrood

Corrosion Research

The disposal of nuclear waste is a demanding topic, and the existing methods, whether it is temporary storage in spent fuel pools or storage in geological repositories, both face the risk of corrosion-related problems. Any failure in these storage methods can potentially lead to the release of radioactive materials into the environment. To avert such catastrophic scenarios, people in the nuclear industry consistently monitor and maintain these storage facilities endlessly and attempt to improve the plans designed to store nuclear waste. Here, I will examine the nuclear waste management organization (NWMO) plan in Canada. Choosing an appropriate location for the …

Remote Laboratory For Nuclear Security Education, Anthony R. Galindo, Craig Marianno

International Journal of Nuclear Security

Laboratory experiences for online students are very limited. To fill this gap, educators in the Department of Nuclear Engineering at Texas A&M University developed a series of radiation detection experiments for their remote students. Radiation detection is only one piece of nuclear security. The objective of the current research is to describe the development and execution of three online laboratories that investigate the basic application of physical security sensors that use light, ultrasonics, and heat to detect adversaries. This laboratory complements lecture material from the department’s Nuclear Security System and Design course. Using the Remote Desktop Application, students connect to …

Comparison Of End-Point Energies Of Bremsstrahlung Photons From 28 Ghz Ecr Ion Source In Three Measurement Locations, Mwingereza John Kumwenda Dr

Tanzania Journal of Engineering and Technology (TJET)

Bremsstrahlung photons measurement show elevated energy emission beyond critical energy in 28-GHz ECR and its nature is not revealed. Thus, the aim of this study is to unveil the nature of high end-point energies at the three measurement locations. Bremsstrahlung photons from a 28-GHz ECR ion source were measured at Busan center of Korean Basic Science Institute (KBSI). The gamma-ray detection system consists of three round type NaI(Tl) scintillation detectors placed 62 cm radially from the beam axis at the three measurement locations namely injection, centre and extraction sides of an ECR ion source, and a NaI(Tl) scintillation detector placed …

3d Cfd Simulation Of A Bubble Column With Internals: Validation Of Interfacial Forces And Internal Effects For Local Gas Holdup Predictions, Hayder Al-Naseri, J. P. Schlegel, Muthanna H. Al-Dahhan

Nuclear Engineering and Radiation Science Faculty Research & Creative Works

CFD models (turbulent models and interfacial forces) incorporated with the population balance model (PBM) have been validated, azimuthally, with the gamma-ray-computed tomography (CT) results to address the effect of the presence of internals with different arrangements and diameters. the superficial gas velocity applied was varied from 0.05 to 0.45 m/s. the results exhibit the capability to predict the hydrodynamics of the bubble column, further incorporating the population balance model and promoting the prediction of simulation in high superficial gas velocity. the effect of internals revealed that the gas holdup was significantly enhanced in the bubble column's wall region, while the …

Defect Generation Mechanisms In Silica Under Intense Electronic Excitation By Ion Beams Below 100 K: Interplay Between Radiative Emissions, M. L. Crespillo, Joseph T. Graham, W. J. Weber, F. Agulló-López

Nuclear Engineering and Radiation Science Faculty Research & Creative Works

Ion-beam effects on bulk silica at low temperature have been studied with the aim of understanding the routes and mechanisms leading from the initial generation of free carriers and self-trapped excitons (STEs) to the production of two stable defect structures in irradiated silica, non-bridging oxygen hole centers (NBOHCs) and oxygen deficient centers (ODCs). Ion beam induced luminescence (ionoluminescence, IL) spectra were obtained using 3 MeV H, 3.5 MeV He, 19 MeV Si, and 19 MeV Cl ions and a range of cryogenic irradiation temperatures from 30 to 100 K. The kinetic behavior of three emission bands centered at 1.9 eV …

Direct Measurement Of The 114cd(N, Gamma)115cd Cross Section In The 1 Ev To 300 Kev Energy Range, Kofi Tutu Addo Assumin-Gyimah

Theses and Dissertations

The large thermal cross section of cadmium makes it ideal for many practical applications where screening of thermal neutrons is desired. For example, in non-destructive assay techniques, or for astrophysical studies of the s-process. All such applications require precise knowledge of the neutron-capture cross section on cadmium. Although there are some data on neutron-capture cross sections particularly at thermal energies and at energies relevant for astrophysics, there is very little data at most other energies. Further, the evaluated cross sections from the ENDF and JENDL databases disagree at high energies. Therefore, there is a critical need for precise knowledge of …

A Comparison Of Fixed Versus Moving Eulerian Meshes For 1-D Radiative Shock Problems, Dylan Weatherred

Nuclear Engineering ETDs

Testing codes used to solve the radiation-hydrodynamics equations requires the use of radiative shock problems. These problems contain stiff shocks and test the coupling of the material motion and the energy exchange between the radiation and material. However, these problems are difficult to solve due to large differences in time scale between radiation and material equations, resolving shocks, and modeling radiation and material interactions. This thesis will look to solve radiative shock problems in 1-D using the Eulerian formulation on fixed and moving meshes. The moving mesh method proposed takes advantage of the more simple Eulerian formulation of the radiation …

Preparation Of High Entropy Titanite Pyrochlore And Radiation Stability Study, Adam Gootgeld

All Theses

Pyrochlore has been studied as a host phase for safe storage of radionuclides and exists naturally with long-term stability with good long-range order [1]. High entropy oxides show promising tunable properties that could demonstrate favorable bulk deposit of radioactive materials such as spent nuclear fuel (Uranium and other actinides). It is proposed that using high entropy oxides (HEOs) as the cation in this framework will shift the gibbs free energy so that radioactive nuclear waste will be stabilized for safe, long-term, eco-friendly storage. We have established a consistent method to fabricate high entropy titanite pyrochlores. In this study, ion beam …

Miniature, Submersible Electromagnetic Pumps Of Molten Lead And Sodium For Gen-Iv Nuclear Reactors Development, Ragai M. Altamimi

Nuclear Engineering ETDs

Heavy metals and alkali Liquid Metals are suitable coolants for Generation IV terrestrial nuclear reactors for operating at elevated temperatures for achieving plant thermal efficiency more than 40% and the thermochemical generation of hydrogen fuel. In addition, the low vapor pressure of these liquids eliminates the need for a pressure vessel and instead operates slightly below ambient pressure. A primary issue with the uses of these coolants is their compatibility with nuclear fuel, cladding and core structure materials at elevated temperatures more than 500oC. Therefore, in pile and out-of-pile test loops have been constructed or being considered for quantifying the …

Electrochemical Approaches To Life-Support Resources In Space Missions And Nuclear Technologies: Hydrogen Peroxide And Uranium Films, Armando Manuel Pena-Duarte

Open Access Theses & Dissertations

Space race has developed several technological advances that have achieved and continue to achieve the success of space missions in the aerospace timeline. Currently, the number of space technical and scientific innovations is still growing––demanding new materials and developments for extreme performing applications of fuel cells, batteries, supercapacitors, and systems of nuclear energy. Space missions require life-support solutions, auto-sustainable closed-loop living environments, cleaning and sanitizing solutions against pathogens, and safe nuclear-based resources of energy––with fissile materials with well-controlled dimensions within the core fuel elements. Likewise, to guarantee safety conditions, reduce costs, and facilitate operational logistics, space missions must reduce their …

Sensitivity And Uncertainty Analysis Of Inertial Confinement Fusion Experiments, Colin A. Weaver

Nuclear Engineering ETDs

Sandia National Laboratories conducts Magnetized Liner Inertial Fusion (MagLIF) experiments at the Z Pulsed Power Facility. Their objective is to study the burning plasma formed under magnetic direct drive Inertial Confinement Fusion (ICF) conditions and use the inferred information to reduce uncertainty in computational models and improve experimental designs. The Z machine has five neutron time-of-flight (nToF) detectors that measure the fusion neutron time spectrum from three lines-of-sight. Together, these signals are used to infer the ion temperature, target liner mass density, and the burn history of the MagLIF experiment from measured data. These parameters are a few used by …

Measurements Of Scintillation Light Quenching For Protons In Rare-Earth Inorganic Scintillators, Tatiana Nathaly Espinoza

Nuclear Engineering ETDs

Scintillator detectors have become a leading choice of radiation detectors for a variety of applications, including space science. Due to their intrinsic characteristics, rare-earth inorganic scintillators provide the capability to detect both gamma and charged particles in a small detector. The response of these detectors is typically characterized using isotropic gamma sources. However, the light output produced in the scintillator from an incident gamma of a particular energy differs from the light output produced from an incident charged particle of the same energy; a phenomenon known as quenching. Using two types of rare-earth inorganic scintillators, Y2SiO5(YSO:Ce), and Gd₃Al₂Ga₃O₁₂(GAGG:Ce), we measured …

Conceptual Design And Preliminary Safety Analysis Of A Proposed Nuclear Microreactor For Mobile Application, A. S. M. Fakhrul Islam

Theses and Dissertations

Conceptual design and preliminary safety analysis of a proposed helium-cooled Micro Nuclear reactor In ONe megawatt (MINION) thermal output is done through three-dimensional computational analysis. Compared with the conventional high temperature gas-cooled reactors (HTGR) that use tri-structural or bi-structural isotropic (TRISO or BISO) fuel particles, MINION uses traditional clad fuel pellets. This greatly simplifies the core design and allows for a substantially more compact design thanks to the fuel’s signif-icantly higher U-235 atom density. Uranium carbide (UC) enriched up to 19.75% in U-235 is used as fuel. In the power-flattened design, U-235 enrichment varies radially between 19.75% and 10.5% in …

Vi Energy-Efficient Memristor-Based Neuromorphic Computing Circuits And Systems For Radiation Detection Applications, Jorge Iván Canales Verdial

Electrical and Computer Engineering ETDs

Radionuclide spectroscopic sensor data is analyzed with minimal power consumption through the use of neuromorphic computing architectures. Memristor crossbars are harnessed as the computational substrate in this non-conventional computing platform and integrated with CMOS-based neurons to mimic the computational dynamics observed in the mammalian brain’s visual cortex. Functional prototypes using spiking sparse locally competitive approximations are presented. The architectures are evaluated for classification accuracy and energy efficiency. The proposed systems achieve a 90% true positive accuracy with a high-resolution detector and 86% with a low-resolution detector.

Material Reliability For A Molten Chloride Salt System, Aaron A.H. Overacker

Nuclear Engineering ETDs

Energy efficiency and cost reduction can both be improved upon using overall higher temperatures for the working fluid. This interest is shared in both nuclear energy as well as concentrated solar power. To achieve higher temperatures would require industry to change working fluids. The United States Department of Energy set out a goal of operating concentrated solar to above 700℃. This would help reduce the cost by having more efficiency in the thermal energy storage, while not a concern for nuclear, these high temperatures can reduce the safety risk and pressure use with the implementation of molten salts. The National …

Molecular Dynamics Study For Tritium Adsorption On Novel Materials, Jason Viscardi, Benjamin Robinson, Asher Flanagan

Symposium of Student Scholars

In this study, novel materials will be researched, and their potential uses for tritium control. 12 studies have been collected on various materials that give a solid foundation for future research that will be conducted regarding tritium control. All these studies used molecular dynamics simulation (MDS) to generate results. The first paper found from a university in Crete, Greece discussed pillared graphene to store hydrogen in a novel 3D carbon nanostructure in which pore size and surface area can be adjusted to suit the need. This was the first of several studies that aim to arrange the graphene in such …

Understanding The Behavior Of Upper Subcritical Limit Calculations, Bobbi Riedel

Nuclear Engineering ETDs

This research consists of two comparison studies: the first study employed standard practices to characterize Upper Subcritical Limit (USL) estimation methods. A series of 33 neutronic systems that used standardized nuclear data and benchmark libraries were studied to compare the Whisper, TSURFER, and USLSTATS methods relative to a stochastic USL. USLs were also estimated for these 20 systems using the Whisper 1.1 code. Sensitivity data files were produced using MCNP6.2 and then used with the ORNL TSURFER and USLSTATS methods to estimate USLs for a cross-method USL comparison. The results show that USLs for each of the loosely coupled system …

Application Of An Empirical Density Law Via Python For Aqueous Plutonium Nitrate Systems, Tara L. Robertson

Nuclear Engineering ETDs

A predictive density tool has been developed to reduce bias and uncertainty in nuclear criticality safety calculations for aqueous plutonium nitrate systems. Multiple methods to calculate the density were reviewed and an empirical method was selected for use. The selected method was then implemented into a Python tool to calculate the solution density and the atom densities for an MCNP6.2 input file.

The Python tool has been validated and verified against the International Handbook of Evaluated Criticality Safety Benchmark Experiments to predict densities within ± 2.6%. The capability to calculate and utilize densities from this tool is a large improvement …

Numerical Study Of Turbulent Flow And Heat Transfer In A Novel Design Of Serpentine Channel Coupled With D-Shaped Jaggedness Using Hybrid Nanofluid, Raditun E. Ratul, Farid Ahmed, Syed B. Alam, Md Rezwanul Karim, Arafat A. Bhuiyan

Nuclear Engineering and Radiation Science Faculty Research & Creative Works

This Study Aimed to Examine Numerically the Effects of a Dimpled Surface over a Mini-Channel Heat Exchanger on the Flow Characteristics and Heat Transfer Across a Serpentine Channel with a Uniform Rectangular Cross-Section. the Dimples Were Arranged in Parallel with a Spanwise (Y/d) Distance of 3.125 and Streamwise (X/d) Distance of 11.25 Along Just One Side of the Serpentine Channel's Surface. Turbulent Flow Regime with Reynolds Number Ranging from 5 X 103 to 20 X 103 in the Channel with the Surface Modification Was Studied using Water and Various Volume Concentrations (Φ = 0.1%, 0.33%, 0.75%, 1%) of Al2O3-Cu/water Hybrid …