Nuclear Engineering ETDs

Publication Date

7-5-2012

Abstract

Although nuclear transmutation methods have been around for decades, they all focus solely on neutron induced reactions. Recent novel concepts have sought to use neutrons as well as photons for active interrogation of cargo to detect the smuggling of highly enriched uranium -- a concept that would require modeling of the transmutation caused by both neutrons and photons. As photonuclear transmutation has yet to be modeled, new methods need to be developed. The CINDER2008 nuclear transmutation code from Los Alamos National Laboratory is extended from neutron only applications to dual particle applications specifically for this modeling. To couple these calculations to a dual particle transport for the determination of reaction rates, both deterministic and Monte Carlo methods are used. By doing this through a single code, TINDER (Transport-coupled CINDER), transport and transmutation calculations can be completed with no human interaction after the start of the calculation, cutting down on the uncertainties and errors that come with human manipulation of data. A necessary verification and validation of these methods has taken place, especially in terms of the photonuclear data, which is sparse or non-existent in some cases. This has proven any data translations and uses are appropriate and correct and the code has been modified correctly. A final demonstration has been performed based on the intended use of this code, active interrogation of nuclear cargo. These results match to within a few percent of experimental data and the extension to dual particles can bolster the output signal by over 15%. As transport methods come at a cost, a sensitivity analysis has been performed to see the effect of variations in the flux on the final output. These results show that although the output beta-delayed photon spectrum is sensitive to the input flux, the results are still on the correct order for practical purposes.

Document Type

Dissertation

Language

English

Degree Name

Nuclear Engineering

Level of Degree

Doctoral

Department Name

Nuclear Engineering

First Committee Member (Chair)

Arthur, Edward

Second Committee Member

Prinja, Anil

Third Committee Member

Coutsias, Evangelos

Fourth Committee Member

Hecht, Adam

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