The Mars Hopper is an alternative extraterrestrial vehicle for the collection of samples from the Martian surface. This thesis studied the engine of the Mars Hopper to assess the validity of the current planned launch cycle according to current parameters. To do this, the engine was simplified to an average...
Medical Isotopes are a necessity in modern medicine for cancer treatments and medical imaging. In order to ensure that the needs and demands are met for the medical procedures, facilities are put in place to produce these isotopes. There are over 25 different isotopes of interest being produced by more...
A limited scope Probabilistic Risk Assessment (PRA) of a vented nuclear fuel system for a Generation IV Gas-Cooled Fast Reactor Plant was performed. The goal of the study was to better understand the safety and licensing implications of vented fuel technology. A Level 1 PRA was performed to determine the...
Nuclear Thermal Rocket (NTR) designs have received renewed interest due to their superior thermal efficiencies and a rehabilitated desire for space exploration. This has resulted in improved NTR fuel designs that have unique properties that require investigation and testing in order to be more safely designed and operated.
Oak Ridge...
A transient code (TFETC) for calculating the temperature
distribution throughout the radial and axial positions of a
thermionic fuel element (TFE) has been successfully developed.
It accommodates the variations of temperatures, thermal power,
electrical power, voltage, and current density throughout the
TFE as a function of time as well as...
A Fabric Composite Radiation Heat Transfer Study has been
conducted to determine the effective emissivities of specific
fabric composite materials. The weave of the fabric and the
high strength capability of the individual fiber in
combination with the thermal conductivity and chemical
stability of specific metallic liner, result in a...
The Run-Ahead Predictive Simulation Software (RAPSS) is an architecture designed for faster-than-real-time decision support for operators of complex networks. To enable further development of the RAPSS methodology, the necessary proof of principle is illustrated in two applications: decision support for shift technical advisors in nuclear power plant control rooms (RAPSS-STA),...
The ion implantation process is a very precise, controllable, and
reproducible method used to enhance material properties of finished
components such as ball bearings. Essentially, the target material is
bombarded by accelerated ions to form a thin alloyed layer in the
substrate. As the ions deposit their kinetic energy in...
Lattice bum-up calculations in thermal reactors are complicated by the necessity
for use of transport theory to represent fuel rods, control rods, and burnable absorbers,
by many time-dependent variables which must be considered in the analysis, and by
geometric complexity which introduces time-dependent, spatial-spectral variations.
Representation of lattice structure in...
The development of a novel high temperature space radiator is
described. A Rotating Bubble Membrane Radiator (RBMR) combines the
best features of heat pipes and droplet radiators while avoiding
their negative attributes. The RBMR offers light weight, self
deployment, ease of startup and its performance is less affected by
acceleration....
A rotating, flat plate condensation experiment has been developed to
investigate the heat of the Rotating Bubble Membrane Radiator (RBMR). The
RBMR is a proposed heat rejection system for space applications which uses
working fluid condensation on the inside surface of a rotating sphere to
reject heat to space. The...
Conventional stainless steel - water and ceramic fabric composite water
heat pipes have been built and tested. The tests have been conducted to compare
the performance characteristics between conventional and fabric composite heat
pipe radiators for space nuclear power heat rejection systems. The fabric
composite concept combines a strong ceramic...
The need for cheap reliable energy, while simultaneously avoiding uranium supply constraints makes uranium carbide (UC) fueled Gas Fast Reactors offer an attractive nuclear reactor design. In order to qualify the fuel, an enhanced understanding of the behavior of uranium carbide during operation is paramount. Due to a reduced re-solution...
Critical Heat Flux (CHF) is an important safety parameter for the design of nuclear reactors. The most commonly used predictive tool for determination of CHF is a look-up table developed using tube data with an average hydraulic test diameter of 8 mm. There exist in the world today nuclear reactors...
Miniature satellites called cubesats have been gaining increasing popularity in
both academic and private spaceflight ventures. NASA's Jet Propulsion Laboratory
has recently been accepting design proposals for a cubesat mission to Europa, where
solar and battery power would be inadequate power sources. In this thesis, a
radioisotope powered cubesat was...
The design of a fabric composite heat pipe has been completed. It is
composed of two end caps, between which a fluid containment liner composed of
metal foil and an outer structural layer composed of a ceramic fabric is stretched.
The interior of the heat pipe is layered with a...
A model has been developed to predict the long-term
oxidation rate of Zircaloy-4 for ex-reactor (autoclave) and
in-reactor (PWR) environments and operating conditions. A
computer program has been written to solve the oxygen
diffusion equation by employing a fully implicit finite
difference method for a one dimensional cylindrical
geometry. The...
This thesis covers two topics. The first subject
involves tests run on a ultralite reflux tube supplied by
Battelle Pacific Northwest Laboratories (PNL). The second
topic involves tests to determine the relative wicking rates
of several different fabrics.
The ultralite reflux tube supplied by PNL was
constructed of copper and...
Oregon State University has conducted research in collaboration with TerraPower, LLC,
to perform a top-down scaling analysis of an integrated test facility. The goal of this
facility is to simulate transient and quasi-steady phenomena at a reduced scale,
including steady-state operation, pump coastdown, natural circulation, reactor head heat
transfer, and...
The goal of this project was to pave the way for more data-driven decision making when considering safety within Nuclear Engineering by proving the concept of new and innovative accident scenario modeling techniques for the analysis of the economics of nuclear safety margins. To do this, a simple, if extremely...
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...
Five Ultra light Fabric Reflux Tubes (UFRTs) were tested in a thermal vacuum chamber at the National Aeronautics and Space Administration's Johnson Space Center in September 1994. These test articles were design and fabricated by staff at the Pacific Northwest Laboratory, operated by Battelle Memorial Institute for the United States...
The NKUA1 is a Small Fission Surface Power (SFSP) space reactor intended for use in upcoming missions to Mars and the moon between the years 2020-2030. The concept of the reactor was created by Dr. Lee Mason and his research team in a joint effort between the Department of Energy...
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...
Safety concerns at the Hanford Reservation require a way to measure the
moisture content of material contained in the high level radioactive waste tanks. The
freezing of material next to a probe was proposed by scientists at Pacific Northwest
Laboratories (PNL) as one approach to solve this problem. It was...
An overall systems design code was developed to model
an advanced in-core thermionic energy conversion based
nuclear reactor system for space applications at power
levels of 10 to 50 kWe. The purpose of this work was to
provide the overall shell for the systems code and to also
provide the...
Preliminary nuclear design studies have been completed on ten
configurations of nuclear reactors for low power (1-30 kWe) space
applications utilizing thermionic energy conversion. Additional design
studies have been conducted on the TRICE multimegawatt in-core
thermionic reactor configuration. In each of the cases, a reactor
configuration has been determined which...
The International Handbook of Evaluated Reactor Physics Benchmark Experiments contains detailed descriptions of many different reactor facilities. A large portion of these experiments have not been fully modeled due to the unavailability of computational power at the time of the experiment’s execution. With the advent of renewed interest in Sodium...
In the wake of nuclear accidents such as Three Mile Island Unit 2 and Fukushima, the nuclear power industry’s safety record is scrutinized. Today the main concerns lies with hydrogen production in a nuclear reactor core when the zirconium fuel cladding reacts with the water coolant during an accident, creating...
A study of the oxidation of zircaloy in reactor
environments has been undertaken with the goal of
characterizing of the Thermal Gradient Test Facility
(TGTF) at Teledyne Wah Chang, Albany. A set of
oxidation models is presented from the literature, as
well as an extensive database of published oxidation
test...
Incore thermionic space reactor design concepts which operate at a
nominal power output range of 20 to 50 kWe are described. Details of the
neutronic, thermionic, thermal hydraulics and shielding performance are
presented. Due to the strong absorption of thermal neutrons by natural
tungsten, and the large amount of that...
The elimination of soluble boron creates several advantages for Small Modular Reactor (SMR) operation. Most of these advantages are realized through significant core simplification (removal of pipes, pumping, and purification systems), the removal of the corrosive effects of soluble boron, and from improved safety effects. However, removing soluble boron creates...
High Temperature Gas Reactors (HTGRs) are positioned to disrupt local and global markets via their unique ability to produce carbon-free process heat, high efficiency power generation, and passively safe operational features. However, significant impediments still exist to delay deployment of this particular technology, including a lack of experimental data, verified...