Browsing Engineering  Nuclear (MS) by Title
Now showing items 120 of 29

[20090827] Analysis of momentpreserving methods for charged particle transport
The simulation of electrons, protons, and other charged particles can be an expensive computation. On the one hand, the small mean free path of a charged particle makes direct simulations very costly. On the other hand, ... 
[20130130] Behavior and measurement of distributed sources in a shielding matrix using gamma spectroscopy
As part of its mission, the Department of Energy generates transuranic waste materials. Some of these wastes are present in large waste containers. The accurate assay of these waste materials in large containers poses ... 
[20150128] Characterization of the Neutron Irradiation System for use in the LowDoseRate Irradiation Facility at Sandia National Laboratories
The objective of this work was to characterize the neutron irradiation system consisting of americium 241 beryllium (241AmBe) neutron sources placed in a polyethylene shielding for use at Sandia National Laboratories’ (SNL) ... 
[20130903] Comparing water to DNA for simulation of Auger electron direct damage to DNA using Geant4
Typically water is used as an analog material for Deoxyribonucleic Acid (DNA) in Monte Carlo simulations of biological radiation interactions. Prior to this work, it was unclear whether water is an appropriate standin for ... 
[20100209] Criticality alarm system design guide with accompanying alarm system development for the Radiochemical Processing Laboratory in Richland, Washington
A detailed instructional manual was created to guide criticality safety engineers through the process of designing a criticality alarm system (CAS) for Department of Energy (DOE) hazard class 1 and 2 facilities. Regulatory ... 
[20100624] Development of sensitivity analysis with the use of TSUNAMI3D sensitivity coefficients for benchmark uncertainty analysis
The uncertainty of a critical benchmark experiment is a very important result. This value tells how well each parameter in the system is known and therefore how well the multiplication factor is known. The current method ... 
[20100624] Diagnostics of source distribution and particle population in Monte Carlo source iteration methods
This thesis is concerned with the development of meshinputfree diagnostics for the determination of the iteration at which the source distribution of a Monte Carlo simulation has reached a stationary state, as well as ... 
[20130711] An Effective Methodology for ThermalHydraulics Analysis of a VHTR Core and Fuel Elements
The Very High Temperature Reactor (VHTR) is a GenerationIV design in the conceptual prelicensing phase for potential construction by 20302050. It is graphite moderated, helium cooled reactor that operates at an exit ... 
[20140912] Efficient Multiphysics Coupling for Fast Burst Reactors in Slab Geometry
In this thesis, we discuss a coupling algorithm to model simplified fast burst reactor dynamics. Kadioglu presented a tightly coupled multiphysics algorithm of diffusion neutronics and linear. An implicitexplicit (IMEX) ... 
[20130130] Eigenfunction expansion of the time and spacedependent neutron survival probability equation
Owing to their inherent complexity, stochastic neutron transport problems are often examined by either using highly simplified models to make solutions more accessible, or at the cost of significant computational effort ... 
[20140214] Examining Thin Film AlSb for Room Temperature Gamma Detectors
A thin film semiconductor device was grown by MBE methods, characterized for material quality and evaluated for suitability as a room temperature gamma radiation detector. The objective was to produce a device that was ... 
[20150901] EXPERIMENTAL STUDIES OF THE CHEMICAL EFFECTS OF ZINCBEARING MATERIALS FOLLOWING A LOSSOFCOOLANT ACCIDENT IN A PRESSURIZED WATER REACTOR
Generic Safety Issue191 (GSI191) was developed by the United States Nuclear Regulatory Commission (U.S. NRC) to assess the effect of debris loading on pressurized water reactor (PWR) emergency core cooling systems (ECCS) ... 
[20160201] Fission Multiplicity Distribution Sampling in MCNP6 Criticality Calculations
In the solution of the neutron transport equation, the keffective eigenvalue is related to the average number of neutrons emitted in fission of the system. It can be shown that if the average number of neutrons emitted ... 
[20150128] IDENTIFICATION OF ELECTROREFINER AND CATHODE PROCESSING FAILURE MODES AND DETERMINATION OF SIGNATURESIGNIFICANCE FOR INTEGRATION INTO A SIGNATURE BASED SAFEGUARDS FRAMEWORK FOR PYROPROCESSING
The traditional method of safeguarding nuclear facilities, nuclear material accountancy (NMA), faces many challenges when applied to pyroprocessing facilities. To aid in the safeguarding of these facilities, process ... 
[20150626] Ionization Chamber Design, Development, and Testing for the UNM Fission Fragment Spectrometer
Fission fragment and product inventories play an important role in many areas of nuclear science from simulation of fissioning systems to active and passive interrogation of nuclear materials. The characteristic properties ... 
[20130903] An ionization chamber for fission fragment analysis
Fission fragments play a pivotal role in understanding the entire nuclear fission process, and their effects are widespread to all applications involving nuclear fission: reactor design and maintenance, waste removal, ... 
[20130130] A momentpreserving singleevent Monte Carlo model of electron and positron energyloss straggling
Analog simulation of energy straggling of electrons and positrons is computationally impractical because of longrange Coulomb forces resulting in highly peaked cross sections about small energylosses and extremely small ... 
[20100625] Nonlinear acceleration methods for evenparity neutron transport
Convergence acceleration methods for evenparity transport are being developed that have the potential to speed up transport calculations and provide a natural avenue for an implicitly coupled multiphysics code. An ... 
[20160201] A Novel Neutron Recoil Spectrometer Concept Utilizing HeavyIon Recoils and Time and SpatiallyResolved Sensor
This thesis describes a heavyion recoil neutron spectrometer as an alternative to existing magnetic proton recoil neutron spectrometers for inertial confinement fusion experiments. Whereas existing designs elastically ... 
[20100903] Novel techniques for the detection and localization of attenuated gammaray sources
The use of cylindrical solidcrystal detectors for the detection and removal of gammaemitting sources has become a common practice for the cleanup of radiological contaminated sites. It is often difficult to determine ...