Low-level nuclear power plant outages in the United States can lead to unanticipated costs, potentially compromising the expected operation lifetime of the plant. Nuclear power plants are complex systems of interfacing components and highly regulated processes. This inherent complexity makes predicting outages from system dependencies very challenging. When outages do...
Advanced reactor designs offer many advantages over typical Light Water Reactors (LWRs) including fast neutron capability, passive safety features, and improved performance. While the future for these reactors seems promising, operating and test experience is necessary to further validate such claims. The development of full-scale facilities has proved to be...
This thesis presents a feasibility study of a thorium fueled thermal spectrum breeder-burner reactor that operates without chemical reprocessing. Materials were evaluated for their potential as moderators using standard analytical methods. These materials were then used as moderators to evaluate criticality and enrichment in an infinite fuel pin lattice. The...
Vibration of nuclear power plant components can cause fretting wear and fatigue that can eventually lead to component failure. Flexible, high-aspect ratio components under flow, such as the wire-wrapped cylindrical fuel elements in a liquid metal-cooled fast reactor (LMFR) core, are particularly susceptible to vibration due to their low natural...
This thesis assessed the passive, natural circulation, design for a Bi-Ca-CaH2 cooled microreactor based on initial figures of merit. The values for the figures of merit selected for this thesis were: the maximum temperature in the core should not be more than 150 K above the average core outlet temperature,...
This is the investigation into The generation of high-fidelity multigroup multiband cross sections from Monte Carlo neutron transport simulations. Previous methods for generating multigroup multiband (MGMB) cross sections, and multigroup cross sections, assume an approximate shape for the scalar flux. This approximate flux shape is the product of an energy-dependent...
The metastable isotope of technetium-99 (Tc-99m) is an important diagnostic tool used in the field of nuclear medicine due to the isotope's 6.0 hour half-life, 140.5 keV γ-decay mechanism, and multiple oxidation states [1,2]. Approximately 70% of the world’s nuclear medicine procedures involve the use of Tc-99m [3]. The conventional...
Current research on the topic of advanced reactor fuel types include the use of ultrahigh density Uranium-Molybdenum fuels, towards their use in high-performance research reactors. These reactors operate with high power densities, and the increased cooling requirements therefore place high relevance on the fluid-structure interaction with these fuel elements; therefore...
A scaling analysis of the Oregon State University (OSU) - Multi-Application Small Light Water Reactor (MASLWR) system has been developed, and an existing RELAP5-3D model of the facility was improved. The purpose of this study is to support the research of hybrid energy systems, being led by Idaho National Laboratory...
Mechanical vibrations compromise the integrity of key components of thermal power plants. Without careful design, strong resonances during steady state operation can wear these components to the point of failure, leading to an unsafe situation that may force a plant to shut down. The purpose of this research is to...
The Oregon State University Multi-Application Small Light Water Reactor test facility is employed in a series tests to evaluate condensation heat transfer in small, high pressure containment vessels characteristic of small modular reactor designs under development. This integral system test facility was constructed to demonstrate the feasibility of a pioneering...
This project was a proof of concept of the use of the RAVEN software, a tool developed for the Risk Informed Safety Margin Characterization (RISMC) approach, with RELAP5-3D. This novel approach combines older probabilistic and mechanistic approaches to look at how and why the complex systems of a nuclear power...
Surface transient storage (STS) and hyporheic transient storage (HTS) have functional significance in stream ecology and hydrology. Both provide refugia for aquatic communities and their longer mean residence times (compared to the main flow) increase the potential for biogeochemical reactions that can improve water quality. As STS and HTS have...
Currently there is a great amount of interest in the phenomena of natural circulation as a cooling mechanism for normal operation as well as emergency conditions in nuclear reactors and spent fuel pools. In order to better understand this phenomena for the specific geometry of vertical, heated rods in water,...
At Oregon State University the Multi-Application Small Light Water Reactor (MASLWR) integral effects testing facility is being prepared for safety analysis matrix testing in support of the NuScale Power Inc. (NSP) design certification progress. The facility will be used to simulate design basis accident performance of the reactor's safety systems....
The advances in the nuclear sciences over the past sixty years have yielded many beneficial technologies and applications, such as power generation, food irradiation, and medical diagnostic devices and techniques. However, these advances have also allowed the advent of nuclear and radiological weapons. This paper will focus on one type...
In consideration of the potential use of minor actinides in nuclear fuel, the fission products of several minor actinides (²³⁷Np, ²⁴¹Am, ²⁴²[superscript m]Am, ²⁴³Cm, ²⁴⁴Cm, ²⁴⁵Cm, and ²⁴⁶Cm) were evaluated and compared to the fission products of ²³⁵U. Available data from the Evaluated Nuclear Data File and the Nuclear Database...
The Nevada Test Site (NTS) was the location for at least 100 above ground
Nuclear Weapons tests during the 1950's and early 1960's. Radioactive fallout
from these tests spread to many areas north and west of the NTS. According to
estimates from the NCI and DOE, Washington County, Utah was...
Characteristic methods are widely known to be very accurate approaches to the
solution of numerical transport problems. These methods are most often used for
neutron transport applications (i.e. lattice physics calculations) where spatial cells
are of intermediate optical thickness (O(1) - O(100) mean free paths, depending on
the energy group)...
Most operating power reactors use oxide fuel in the form of uranium oxide (UO2) which is robust against high temperatures but suffers from poor mechanical performance at high levels of burnup. Currently, the maximum average burnup in light water reactors in the US is 62.5 GWd/t, which is partially imposed...