Keywords and Phrases
Gamma Tomography; Monte-Carlo; Radiography; Transport
”Nondestructive characterization techniques such as gamma tomography represent powerful tools for the analysis and quantification of physical defects and radionuclide concentrations within nuclear fuel forms. Gamma emission tomography, in particular, has the ability to utilize the inherent radiation within spent nuclear fuel to provide users with information about the migration and concentration of fission and activation products within the fuel form. Idaho National Laboratory is interested in using this technology to analyze new nuclear fuel forms for potential use in next generation nuclear reactors. In this work, two aspect of the system are analyzed. The first is a semi-analytic radiation transport methodology in conjunction with a parallel beam collimator developed to facilitate the acquisition of data from Monte-Carlo modeling of a small submersible gamma tomography system, with a focus on emission information. The second is a pinhole collimator designed to optimize count rates, diameter, and acceptance angle to increase the sampling of the fuel forms to decrease data acquisition time. Utilizing the semi-analytical technique, computational savings of 107-1011 can be achieved with a degradation in accuracy of 1845% compared to a standard isotropic uniform Monte-Carlo N Particle transport simulation. However, this loss in accuracy can be minimized by increasing the parallel beam collimator’s aspect ratio where it tends towards a degenerate cylinder. The semianalytic technique is also compared to inbuilt acceleration techniques. The pinhole collimator design yields count rates on the order of 100s-1000s which represents a 101-102 increase in actual count rates over the entirety of the photon spectrum”--Abstract, page iv.
Graham, Joseph T.
Alajo, Ayodeji Babatunde
Liu, Xin (Mining & Nuclear Engr)
Nuclear Engineering and Radiation Science
Ph. D. in Nuclear Engineering
Missouri University of Science and Technology
Journal article titles appearing in thesis/dissertation
- A source biasing and variance reduction technique for Monte Carlo radiation transport modeling of emission tomography problems
- Comparison of a semi-analytic variance reduction technique to classical Monte Carlo variance reduction techniques for high aspect ratio pencil beam collimators for emission tomography applications
- Design and optimization of a pinhole collimator for a high-resolution emission gamma ray tomography system
xiii, 120 pages
© 2020 Seth Michael Kilby, All rights reserved.
Dissertation - Open Access
Kilby, Seth, "Development of radiation transport techniques for modelling a high-resolution multi-energy photon emission tomography system" (2020). Doctoral Dissertations. 2935.