Nuclear Engineering Commons^™

Development Of Applicable Benchmark Experiments For (Th,Pu)O2 Power Reactor Designs Using Tsunami Analysis, Stephanie E. Langton

Open Access Dissertations and Theses

When simulating reactor physics experiments, uncertainties in nuclear data result in a bias between simulated and experimental values. For new reactor designs or for power reactor designs the bias can be estimated using a set of experiments. How- ever, the experiments used to estimate the bias must be applicable to the power reactor design of interest. Similarity studies can be performed to ensure this is the case. Here, potential experiments in the ZED-2 heavy water critical facility at Chalk River Laboratories were developed that would be applicable to the multiplication factor bias calculation of three thoria plutonia fuelled power reactor ...

Design Of A Neutron Detector Capable Of Replacing He-3 Detectors Utilizing Thin Polymeric Films, Matthew J. Urffer

Masters Theses

There exists a significant need to develop a new neutron detection system which would reduce the dependency on the current He-3 based detectors for Domestic Nuclear Detection Office (DNDO) applications. One of the technologies being developed is the use of Li-6 (thermal cross section of 940 barns) in scintillating polymeric thin films. The purpose of this research is to provide a framework for the characterization of thin polymeric films in terms of meeting the detection requirements set forth by the governing bodies, most notability a detector count rate of 2.5 cps/ng with and only misclassifying a neutron as ...

Evaluation Of Tagging Techniques Gamma-Decay Probabilities Using The Surrogate Method, Timothy Lee Reed

Masters Theses

A detailed analysis of the statistical and discrete [gamma]-decay tagging techniques was conducted using the absolute surrogate and surrogate ratio method (SRM) to obtain the 92Mo(n,[gamma]) cross section in an equivalent neutron energy range of 80 to 880 keV. Excited 93Mo and 95Mo nuclei were populated using (d,p) reactions on 92Mo and 94Mo targets, respectively. The absolute surrogate 92Mo(n,[gamma]) cross sections disagreed with evaluated neutron capture cross section data by as much as a factor of 4 using the statistical tagging approach, whereas the discrete [gamma]-decay tag absolute surrogate cross section disagreed with ...

Development Of A Novel Technique For Predicting Tumor Response In Adaptive Radiation Therapy, Rebecca Marie Seibert

Doctoral Dissertations

This dissertation concentrates on the introduction of Predictive Adaptive Radiation Therapy (PART) as a potential method to improve cancer treatment. PART is a novel technique that utilizes volumetric image-guided radiation therapy treatment (IGRT) data to actively predict the tumor response to therapy and estimate clinical outcomes during the course of treatment. To implement PART, a patient database containing IGRT image data for 40 lesions obtained from patients who were imaged and treated with helical tomotherapy was constructed. The data was then modeled using locally weighted regression. This model predicts future tumor volumes and masses and the associated confidence intervals based ...

Optimization Of Transcurium Isotope Production In The High Flux Isotope Reactor, Susan Hogle

Doctoral Dissertations

The Radiochemical Engineering Development Center at Oak Ridge National Laboratory is the world's leader in production of californium-252. This and other heavy actinides are produced by irradiation of mixed curium/americium targets in the High Flux Isotope Reactor. Due to the strong dependence of isotopic cross sections upon incoming neutron energy, the efficiency with which an isotope is transmuted is highly dependent upon the neutron flux energy spectrum and intensities. There are certain energy ranges in which the rate of fissions in feedstock materials can be minimized relative to the rate of (n,γ) absorptions. This work shows that ...

Mehanical Characterization Of Ion-Iradiated Silicon Carbide By Nanoindentation, Alex Hackett, Kurt Johanns, Haizhou Xue, Yanwen Zhang, Erik Herbert, George Pharr

EURēCA: Exhibition of Undergraduate Research and Creative Achievement

Tests are done on various types of silicon carbide in order to analyze mechanical properties and radiation resistance.

In-Situ Condition Monitoring Of Components In Small Modular Reactors Using Process And Electrical Signature Analysis, Victor Lollar

Pursuit - The Journal of Undergraduate Research at the University of Tennessee

Components in small modular reactors (SMRs) are located in a hazardous environment and must be monitored remotely. Electrical signature analysis (ESA) is a viable option for component monitoring as it can be implemented on-line away from the actual equipment. This research attempts to use both electrical signatures from a pump motor and process variables such as flow and pressure to effectively monitor reactor components. An experimental flow loop with pump health monitoring equipment and a data acquisition system was used for experiments. Process variables analyzed include pressure, flow rate, water level, and motor vibrations. The electrical signatures monitored were the ...

Analysis Of Transuranic Mixed Oxide Fuel In A Candu Nuclear Reactor, Andrew C. Morreale

Open Access Dissertations and Theses

The reprocessing of spent fuel is a key component in reducing the end waste from nuclear power plant operations and creating a sustainable closed fuel cycle. Central to this effort is the extraction and reprocessing of actinide materials to be recycled into fast or thermal reactors. Reprocessed actinides can contribute additional energy and may be partially transmuted in current thermal systems using mixed oxide fuels before being sent to fast reactors. The use of current thermal reactors as an intermediary step significantly reduces the fast reactor infrastructure needed to handle the spent fuel inventory in the long term, and also ...

Prognostic Approaches Using Transient Monitoring Methods, Michael Eric Sharp

Doctoral Dissertations

The utilization of steady state monitoring techniques has become an established means of providing diagnostic and prognostic information regarding both systems and equipment. However, steady state data is not the only, or in some cases, even the best source of information regarding the health and state of a system. Transient data has largely been overlooked as a source of system information due to the additional complexity in analyzing these types of signals. The development for algorithms and techniques to quickly, and intuitively develop generic quantification of deviations a transient signal towards the goal of prognostic predictions has until now, largely ...

Secondary Light Particle Data Base Development Using A Thermodynamic Coalescence Model, Mahmoud Pourarsalan

Doctoral Dissertations

ABSTRACT

As heavy ions are transported through shielding and interact with shielding materials accurate values of total, elastic scattering, reactions cross sections and angular distributions of the emitted nucleons, light high energy particles such as deuteron, triton, helion, alpha particles and other heavy ions are required in order to design appropriate and adequate shielding to protect the human crews and instruments from ionizing radiations during long duration space missions. Double-differential (energy and angle) light energetic particle production cross sections must be known for ion energies from tens of MeV/nucleon to tens of GeV/nucleon for all emitted light energetic ...

A Validation Study Of The Amp Nuclear Fuel Performance Code, Aaron Martin Phillippe

Masters Theses

The Advanced Multi-Physics (AMP) Fuel Performance Code is a fully coupled, 3-dimensional (3D) code currently in development at the Oak Ridge National Laboratory (ORNL) for the purposes of advanced fuel performance evaluation and simulation. The purpose of this study was to investigate and examine the capabilities of AMP, as developed so far, in thermo-mechanical evaluations of experimental benchmark data. The IFA-432 and IFA-597 datasets from the Nuclear Energy Agency’s (NEA) International Fuel Performance Experiments (IFPE) database were examined, and a code-to-code comparison made against FRAPCON-3.4, a one dimensional (1D) code used by the Nuclear Regulatory Commission (NRC) for ...

The Use Of A Fluidized Bed In A Spent Fuel Pool, Charles R. Menke, Natalie B. Camilli, Nathan A. Capps, Claire Fage, Timothy R. Hillard, Matthew B. Nash, Matthew L. Thornbury

University of Tennessee Honors Thesis Projects

No abstract provided.

Simulation Of Time-Dependent Neutron Populations For Reactor Physics Applications Using The Geant4 Monte Carlo Toolkit, Liam F. Russell

Open Access Dissertations and Theses

When the material or geometry of a reactor varies with time, the neutron flux will respond in the form of a reactor transient. These transients can occur during normal operations when control rods are moved or the reactor is refuelled (CANDU). During a reactor accident, the transient response is especially important because the reactor properties vary quickly with large amplitudes. Therefore, better understanding these conditions allows for improved identification, prevention and mitigation of reactor transients. However, current nuclear simulation codes are generally limited in their ability to model transient behaviour.

The NStable code was created to model time-dependent neutron populations ...

A Controllability Study Of Trumox Fuel For Load Following Operation In A Candu-900 Reactor, David A. Trudell

Open Access Dissertations and Theses

The CANDU-900 reactor design is an improvement on the current CANDU-6 reactor in the areas of economics, safety of operation and fuel cycle flexibility. As power grids start to rely more heavily on nuclear, it will be imperative for future nuclear generating station designs to be able to adjust their output to suit the fluctuating demands of the grid. Additionally, the need to reduce global nuclear waste has motivated research into mixed oxide fuel with the goal of maximizing spent fuel repository capacity and reducing decay heat via transmutation of transuranic actinides. The objective of this thesis is to provide ...

Characterization Of Local Mass Transfer Rate Downstream Of An Orifice, Dongdong Wang

Open Access Dissertations and Theses

Flow accelerated corrosion(FAC) results in wall thinning of pipes, tubes or vessels from exposure to flow due to corrosion. If FAC is not detected, it can lead to sudden failure of piping components. Orifices are used in piping systems to monitor and control the flow. Flow separation and reattachment downstream of an orifice can enhance the mass transfer of the pipe wall. In this thesis, the effect of Reynolds numbers and surface roughness on the mass transfer rate downstream of an orifice was investigated. A dissolving wall method was used to measure the wall mass transfer. The test sections ...