Nuclear Engineering Commons^™

The Role Of Generation Iv Nuclear Reactors In Decarbonising International Shipping : A Multi-Criteria Decision Making (Mcdm) Framework For Matching Potential Decarbonisation Pathways To Different Ship Types And Size, Claudianus David Kunze

World Maritime University Dissertations

No abstract provided.

Thermodynamic Assessment Of Chromium Corrosion In The Na-K-Mg-U(Iii, Iv) Chloride Salt, Jacob Allen Yingling

Theses and Dissertations

Thermodynamic descriptions of high-order molten chloride salt systems are essential for the development of fast molten salt reactor (MSR) technologies. However, a complete thermodynamic assessment of the essential Na-K-Mg-U(III)-U(IV) molten chloride salt with the most prevalent CrCl2 corrosion product has yet to be provided. This is remedied in the present work through application of the CALculation of PHAse Diagrams (CALPHAD) approach to the available thermodynamic data and new measurements that include differential scanning calorimetry (DSC) observations for previously unexplored two and three component chloride salt systems. Through these efforts, a unique approach was developed for the quantification of uncertainty in …

Reinforcement Of The Plasmon–Phonon Coupling In Α-Quartz Via Deposition Of Gold Nanoparticles In Etched Ion Tracks, Maria C. Garcia Toro, Miguel L. Crespillo, Jose Olivares, Joseph T. Graham

Nuclear Engineering and Radiation Science Faculty Research & Creative Works

This study reports a large reinforcement of the plasmon–phonon coupling in alpha quartz achieved through the controlled deposition of gold nanoparticles into nano templates produced through chemical etching of ion tracks. Preferential agglomeration of nanoparticles within the etched ion tracks (nano wells) was observed in Scanning Electron Microscopy and Atomic Force Microscopy images. Raman characterization of quartz substrates with different nanoparticle concentrations revealed a relationship between the plasmon–phonon coupling intensity and nanoparticle concentration. Reinforcement of the plasmon–phonon coupling was observed as an increase in the Raman intensity with increasing concentration of deposited nanoparticles. The intensity initially increased linearly with nanoparticle …

Full Volume 13, Issue 1, Seyma Tufan

Space and Defense

No abstract provided.

Enabling Rapid Chemical Analysis Of Plutonium Alloys Via Machine Learning-Enhanced Atomic Spectroscopy Techniques, Ashwin P. Rao

Theses and Dissertations

Analytical atomic spectroscopy methods have the potential to provide solutions for rapid, high fidelity chemical analysis of plutonium alloys. Implementing these methods with advanced analytical techniques can help reduce the chemical analysis time needed for plutonium pit production, directly enabling the 80 pit-per-year by 2030 manufacturing goal outlined in the 2018 Nuclear Posture Review. Two commercial, handheld elemental analyzers were validated for potential in situ analysis of Pu. A handheld XRF device was able to detect gallium in a Pu surrogate matrix with a detection limit of 0.002 wt% and a mean error of 8%. A handheld LIBS device was …

A Numerical Thermal Analysis Of A Battery Pack In An Electric Motorbike Application, Mohammad Shahjalal, Tamanna Shams, Sadat Bin Hossain, Probir Kumar Roy, Arafat Alam Jion, Mominul Ahsan, Jahedul Islam Chowdhury, Md Rishad Ahmed, Syed B. Alam, Julfikar Haider

Nuclear Engineering and Radiation Science Faculty Research & Creative Works

Today, electric driven motorbikes (e-motorbikes) are facing multiple safety, functionality and operating challenges, particularly in hot climatic conditions. One of them is the increasing demand for efficient battery cooling to avoid the potential thermal stability concerns due to extreme temperatures and the conventional plastic enclosure of the battery pack. A reliable and efficient thermal design can be formulated by accommodating the battery within an appropriate battery housing supported by a cooling configuration. The proposed design includes a battery pack housing made of high conductive materials, such as copper (Cu) and aluminum (Al), with an adequate liquid cooling system. This study …

Computational Methods, Investigations, And Codes To Support Corrosion Experiments In Molten Lead And Transfer To Reactor Conditions, Khaled A. Talaat

Nuclear Engineering ETDs

Lead cooled fast reactors have many potential economic advantages over other Generation IV reactor designs due to the high boiling point of lead (~1750 °C) at atmospheric pressure and excellent neutronic properties which have made them attractive to the commercial energy sector in the recent years. They, however, remain hampered by challenges in cladding material compatibility with the heavy liquid metal coolant. A forced circulation loop was established at the University of New Mexico (“Lobo Lead Loop”) to prequalify materials for Versatile Test Reactor (VTR) testing and to improve the understanding of flow accelerated corrosion in molten lead environment. Corrosion …

Enhancements To Nuclear Thermal Propulsion Rockets, Kimberly Gonzalez

UNLV Theses, Dissertations, Professional Papers, and Capstones

Nuclear thermal rocket propulsion has been proposed as a highly efficient technology for space vehicles traveling from earth orbit to the moon, Mars, and other locations in the solar system. With twice the performance of a chemical rocket, nuclear thermal propulsion (NTP) uses the thrust produced by heating hydrogen gas within a thermal nuclear reactor where the exhaust is then passed through a de Laval nozzle to produce supersonic flow. NTP engines were the subject ofthe NERVA experiments at the Nevada Test Site in the 1970’s, and they produced a specific impulse of up to 900 seconds which is almost …

Modeling The Reactor Time-Dependent Delayed Particle Tail With Monte Carlo N-Particle (Mcnp) Version 6.2, Eli James Boland

Masters Theses

"Energy is deposited into experiment packages due to post-shutdown decay heat created from delayed particles. Modeling these delayed particles in a reactor assists researchers in quantifying the expected energy deposition sources to an experiment package before irradiation. This paper focuses on modeling the delayed particles in a reactor in MCNP6.2 by capturing a reactor as a source, converting this source capture to a source definition, applying appropriate physics such as activation and photonuclear interactions, and finally using proper tallies to create the expected delayed particle tail of a reactor.

To capture the source distribution, the FMESH capability within MCNP was …

Computational Models To Detect Radiation In Urban Environments: An Application Of Signal Processing Techniques And Neural Networks To Radiation Data Analysis, Jose Nicolas Gachancipa

Beyond: Undergraduate Research Journal

Radioactive sources, such as uranium-235, are nuclides that emit ionizing radiation, and which can be used to build nuclear weapons. In public areas, the presence of a radioactive nuclide can present a risk to the population, and therefore, it is imperative that threats are identified by radiological search and response teams in a timely and effective manner. In urban environments, such as densely populated cities, radioactive sources may be more difficult to detect, since background radiation produced by surrounding objects and structures (e.g., buildings, cars) can hinder the effective detection of unnatural radioactive material. This article presents a computational model …

Joining Of Candidate Materials For Lead-Cooled Fast Reactors, Brandon M. Bohanon

Nuclear Engineering ETDs

The lead-cooled fast reactor (LFR) is a fourth-generation reactor design characterized by high temperatures, neutron dosage, and highly corrosive and erosive environment due to high flow velocities. Therefore, materials testing must be performed to find structural and system components that withstand this harsh environment. These candidate alloys must have high-temperature creep strength, resistance to damage from fast-spectrum neutrons, and must grow protective oxide layers. FeCrAl alloys have been identified as possessing all these qualities, however, there are limitations due to erosion and the joining of these materials. In this work, mechanical and microstructural properties of base and conventionally joined FeCrAl-based …

The Effects Of A Power Iteration-Based K-Eigenvalue Solver For Various Subcritical Parameters And Calculations, Daniel H. Timmons

Nuclear Engineering ETDs

The need to simulate subcritical benchmark parameters quickly and accurately is becoming increasing important. When using Monte Carlo methods this is traditionally done using a fixed-source calculation where a particle and its progeny are tracked until their removal from the system. This method can be slow for near critical systems. The use of a k-eigenvalue solver could reduce the computational footprint and reduce the need to post process data.

This is done for four parameters from the ICSBEP benchmark values: R_1 , R_2 , M_L, and M_eff. These parameters are calculated in two new distinct ways. First, is directly …

First-Principles Study Of The Thermal Properties Of Zr2c And Zr2co, Yue Zhou, William Fahrenholtz, Joseph T. Graham, Gregory E. Hilmas

Materials Science and Engineering Faculty Research & Creative Works

First-principles calculations of lattice thermal conductivities and thermodynamic properties of Zr2C and Zr2CO were performed using the quasi-harmonic approximation. Oxygen in the lattice gives Zr2CO higher bonding strength than Zr2C. Thus, the mechanical properties of Zr2C are enhanced when the vacancies in its crystal structure are filled with oxygen. Among the critical parameters that determine the lattice thermal conductivity, Zr2C has significantly higher Grüneisen parameters, thus Zr2C has lower lattice thermal conductivity than Zr2CO. In addition, Zr2CO has a higher heat capacity and thermal expansion coefficient than Zr2C at most temperatures. These results indicate that the addition of oxygen has …

Nuclear Fuel Cycle: Safe Management Of Spent Nuclear Fuel, Robert L. Sindelar

Journal of the South Carolina Academy of Science

The aim for storage of spent nuclear fuel (SNF) either in wet or in dry storage systems is to ensure general safety objectives are met throughout a desired storage period. Staff at the Savannah River National Laboratory (SRNL), in collaborations with partners at other national laboratories, industry research organizations, and the University of South Carolina (UofSC), have performed materials aging testing and analyses, and have established nuclear materials aging management programs to support extended periods of safe storage of research reactor (RR) SNF and of commercial power reactor (PR) SNF pending ultimate disposal. Several example challenges include susceptibility of aluminum …

Simulation Of Thermal Radiation Transport In Stochastic Media With Nonlinear Temperature Dependence, Corey Michael Skinner

Nuclear Engineering ETDs

Nonlinear gray thermal radiation transport (TRT) in binary statistical mixtures is investigated through Implicit Monte Carlo (IMC) simulation on one-dimensional planar Markovian geometries and two dimensional approximate Markovian or Poisson-Box geometries. A stochastic geometry option was implemented in the Los Alamos National Laboratory Branson IMC solver which yielded benchmark solutions by simulating thermal radiation and material energy transport over a large number of instantiations of the geometry followed by ensemble averaging to obtain conditionally averaged radiation intensity and material temperatures. A chord length sampling method was also implemented based on a heuristic generalization of the Levermore-Pomraning homogenized medium model to …

Nuclear Energy As A Reliable And Safe Source Of Power Generation, Sarup Dhungana

Honors Theses

There is a high demand of energy for generating civil applicable power in the world and in the USA, correspondingly. The world has been consuming various sources to extract the power to meet its demands. Most of the power sources include renewable and non-renewable sources like fossil fuels, natural gas, coal, water, solar, wind, and nuclear power. Although most of these sources have many advantages in terms of their capacity and cost of production, nuclear power can be categorized as the emerging driving force in the United States and in the world for power generation, because of its reliability and …

Light Emission Of Self-Trapped Excitons From Ion Tracks In Silica Glass: Interplay Between Auger Recombination, Exciton Formation, Thermal Dissociation, And Hopping, Joseph T. Graham, Miguel L. Crespillo, Fernando Agulló-López, William J. Weber

Nuclear Engineering and Radiation Science Faculty Research & Creative Works

The initial luminescence yield of amorphous silica under ion irradiation has been studied at temperatures between 30 and 100 K, using swift ions of different masses and energies (3 MeV H, 3.5 MeV He, 19 MeV Si and 19 MeV Cl). The intensity of the 2.1 eV emission band, ascribed to the intrinsic recombination of self-trapped excitons (STEs), has been found to vary systematically with ion mass, energy and irradiation temperature. A detailed model has been developed to quantitatively describe those variations in terms of the competition between non-radiative Auger recombination, STE formation, STE thermal dissociation, and subsequent STE hopping …

Reactive Thin Film Polymers And Thin Film Composite Membranes For The Rapid Screening Of Uranium Isotopes, Abenazer W. Darge

All Dissertations

Traditional radiochemistry approaches for the detection of trace-level alpha-emitting radioisotopes in water require lengthy offsite sample preparations and do not lend themselves to rapid quantification. Therefore, a novel platform is needed that combines onsite purification, concentration, and isotopic screening with a fieldable detection system. My dissertation research objective was to develop novel reactive thin polymer films and thin film composite membranes for the selective separation of uranium from environmental water followed by direct isotopic analysis by alpha spectroscopy. Chapter 1 reviews progress made on uranium separation from aqueous matrices and discusses methods used for the determination of isotopic composition.

Chapter …

Viability Of Energy And Fuel Sources For Interstellar Travel; Design And Feasibility Of The Construction Of Manned Interstellar Space Shuttles, Lukas Mittelman

UNLV Theses, Dissertations, Professional Papers, and Capstones

The importance of proving the viability of interstellar transport and addressing its potential hazards and pitfalls is immense. If we do not look toward the future and examine what could be waiting for us, we are doing our children, our children’s children, and so on, a disservice. Here we must attempt to lay the groundwork for our future scientists, engineers, and adventurers. Asking and answering questions like, which propulsion and energy systems must we incorporate to send us through the cosmos? Will we utilize technologies known today, such as fossil fuel rockets, fission or fusion rockets, and antimatter drives (pion …

Electrochemical Impedance Spectroscopy Of Zirconium Oxidation For In-Situ Nuclear Sensing Applications, Michael Andrew Reynolds

Boise State University Theses and Dissertations

To meet the ever-growing energy demands of the modern world, alternative forms of producing power are necessary, and the field of nuclear engineering holds promise to answer this call. Nuclear fuel cladding in light water reactors (LWRs) currently draws a large amount of attention from scientists and researchers, as it provides many challenges to design around. Since the 1950s, zirconium and its protective oxide layer have been utilized as an effective material for the task, possessing good mechanical strengths, high corrosion resistance, and a low neutron absorption cross section. Despite these beneficial properties, however, fuel cladding remains vulnerable to several …

Towards Improving The Properties And Furthering Acceptance Of Advanced Technology Nuclear Fuels, Jennifer K. Watkins

Boise State University Theses and Dissertations

To avoid detrimental environmental impacts from climate change, the world community needs to push for the use of clean energy technologies. Development of proposed advanced technology nuclear fuels supports efforts to ensure nuclear energy is included as a non-carbon emitting source of electricity generation. Advanced technology nuclear fuels, also referred to as accident tolerant fuels (ATFs), have received renewed interest for use in the current nuclear reactor fleet as well as in advanced reactor technologies due to their high uranium loading, desirable thermophysical properties, and performance under irradiation as compared to the benchmark oxide fuel. A limiting consideration for the …

Wetland Uranium Transport Via Iron-Organic Matter Flocs And Hyporheic Exchange, Connor J. Parker

All Dissertations

Uranium (U) released from the M-Area at the Department of Energy Savannah River Site into Tims Branch, a seasonal wetland and braided stream system, is estimated to be 43,500 kg between 1965 and 1984. The motivation for this work is the uranium’s persistence in the wetland for decades, where it is estimated that 80% of the U currently remains in the Tims Branch wetland. U has begun to incorporate into wetland iron (Fe) and carbon cycles, associating with local Fe mineralogy and deposits of rich wetland organic matter (OM). The objective of this work is to characterize the chemical phases …

Experimental Investigations On Boiling Heat Transfer Characteristics Of Accident-Tolerant-Fuel And Traditional Claddings, Mingfu He Mr.

Nuclear Engineering ETDs

To make it more clear that how the materials’ thermal-physical properties and wall thickness have influential impacts on boiling heat transfer characteristics of cladding, this dissertation looks into the potential impacts of cladding materials on critical heat flux and heat transfer coefficients by a systematic experimental investigation across a wide range of pool/flow boiling conditions under the steady-state and power-transient heat inputs.

Recent thermal-hydraulics studies have demonstrated that iron-chromium-aluminium (FeCrAl) alloys have the thermal priorities over zircaloys and other commercial alloys including critical heat flux and heat transfer coefficient. However, it is found in our experimental results that FeCrAl-C26M, and …

Utilizing Sensitivity And Correlation Coefficients From Mcnp And Whisper To Guide Microreactor Experiment Design, Alexis Maldonado

Nuclear Engineering ETDs

When designing experiments for full-scale reactor systems, MCNP and Whisper can be used to create neutronic models and compare the similarity of two nuclear systems via correlation coefficients for 𝑘𝑒𝑓𝑓, effective multiplication factor. This thesis applies this framework to a conceptual heat-pipe, yttrium-hydride moderated microreactor system and experiments. The framework is intended as a supplement to other neutronics/thermal/multiphysics analyses and provides a concrete method to measure the neutronic similarity of two systems. By analyzing the shared nuclear data uncertainty, as well as sensitivity to nuclear data over all neutron energies, highly informative experiments can be designed to aid in the …

Thermal-Hydraulic System Analysis Of A Proposed 1 Mwth Nuclear Gas Cooled Microreactor, Aaron S. Fernandez

Theses and Dissertations

Nuclear power plants have historically been large, expensive, and prolonged construction projects. A new generation of reactors categorized as microreactors is currently being designed to address energy needs in remote locations. The University of South Carolina has proposed the MIcro Nuclear In ONe megawatt (MINION-1) design to achieve ten years of operation. The primary loop transfers 1 MW of energy from the reactor core using helium, while the secondary uses air in an open Brayton cycle to produce power and heat. This work focuses on modeling the MINION-1 design using the System Analysis Module (SAM) developed by Argonne National Labs …

Mechanistic Multiphysics Modeling Of Cladding Rupture In Nuclear Fuel Rods During Loss-Of-Coolant Accident Conditions, Kyle Allan Lawrence Gamble

Theses and Dissertations

The Loss of Coolant Accident (LOCA) is a design basis accident that is included as part of the safety analysis of nuclear power plants. As the nuclear industry desires to increase the cycle length and discharge burnup of existing nuclear power plants they must demonstrate safe operation during a LOCA on high burnup fuel. During a LOCA transient on high burnup fuel rods, the rods may undergo a process known as fuel fragmentation, relocation, and dispersal (FFRD). To permit dispersal, the cladding encapsulating the fuel must rupture with an opening size large enough to allow the fragmented fuel particles to …

Aerial Radiation Detection Identification And Measurement System Detector Material Comparison Study, Benjamin C. Troxell, Kacey D. Mcgee, Christina L. Dugan

Faculty Publications

The 20th Chemical Biological Radiological Nuclear and Explosives Command (CBRNE) currently utilizes an airborne sodium iodide gamma and beta detection system to map radiation fields over large areas of interest. The 20th CBRNE explored emergent detector technologies utilizing two detection materials; thallium-activated cesium iodide and high purity germanium (HPGe). These detectors were simulated at various altitudes and compared to background measurements. The sodium iodide detector failed to provide isotopic discrimination at distance. The thallium-activated cesium iodide CsI(Tl) detector provided sufficient absolute efficiency and energy resolution to identify isotopics at distance. The HPGe detector provided the best energy resolution. However, current …

Capability Development For Advanced (N,X) Nuclear Data Measurements, Brian G. Frandsen

Theses and Dissertations

Nuclear reaction data are the heart of radiation transport calculations, models, and simulations. Unique approaches are required to improve the measurement capability for many reactions where data are inaccurate or do not exist. First, the newly developed Gamma Energy Neutron Energy Spectrometer for Inelastic Scattering (GENESIS) provides the ability to measure neutron inelastic scattering cross sections on different targets. An initial experiment measuring the ¹⁶O(n,n’��) reaction calculated the count rate from the second excited state using the full energy and escape peaks. Second, a set of photocurable scintillator resin formulations capable of neutron-gamma discrimination were developed to support light-based …

Verficiation And Validation Of Unstructured Meshing Capabilities In Mcnp6, Micah C. Jeroutek

Theses and Dissertations

Discrepancies were found between the legacy CSGs and the new UMs with the latter's introduction in MCNP6. As such, V&V of UMs in MCNP must be conducted to assist in their further development and increase user confidence in them. Currently, the MCNP test suite is lacking in UM benchmarks, and of the few that are present, their range in problem type is limited. To address these issues, two preliminary test cases covering new applications of UMs were developed for future inclusion in the test suite. The first was for the Athena-I experiment which involved the study of electronic devices' responses …

Modeling Gadolinium Self Powered Neutron Detectors In A Transient Reactor, Alexander L. Q. Spring

Theses and Dissertations

Contributions to the electron current from the three components of a gadolinium SPND, emitter, insulator, and sheath, are identified, characterized, and quantified to provide information on how the SPND interacts within the transient neutron and photon flux of the TREAT to create a measurable current. These contributions are measured by defining the SPND interactions as a dose response function used within a Monte Carlo simulation of a TREAT experiment. The data obtained from the Monte Carlo simulations are then used to compare against two analytic models, developed by Jaschik and Warren, as well as the experimental results. It was found …