K. E. Chesson,
"A One-Group Parametric Sensitivity Analysis for the Graphite Isotope Ratio Method and Other Related Techniques Using ORIGEN 2.2,"
M.S. Thesis, Texas A & M University, August 2007.
Several methods have been developed previously for estimating
cumulative energy production and plutonium production from
graphite- moderated reactors. The Graphite Isotope Ratio Method
(GIRM) is one well-known technique. This method is based on the
measurement of trace isotopes in the reactor's graphite matrix to
determine the change in their isotopic ratios due to burnup. These
measurements are then coupled with reactor calculations to
determine the total plutonium and energy production of the reactor.
To facilitate sensitivity analysis of these methods, a one- group
cross section and fission product yield library for the fue l and
graphite activation products has been developed for MAGNOX-style
reactors. This library is intended for use in the ORIGEN computer
code, which calculates the buildup, decay, and processing of
radioactive materials. The library was developed using a fuel cell
model in Monteburns. This model consisted of a single fuel rod
including natural uranium metal fuel, magnesium cladding, carbon
dioxide coolant, and Grade A United Kingdom (UK) graphite. Using
this library a complete sensitivity analysis can be performed for
GIRM and other techniques. The sensitivity analysis conducted in
this study assessed various input parameters including 235U and238U
cross section values, aluminum alloy concentration in the fuel, and
initial concentrations of trace elements in the graphite moderator.
The results of the analysis yield insight into the GIRM method and
the isotopic ratios the method uses as well asthe level of
uncertainty that may be found in the system results.
Associated Project(s):Sensitivity Analysis for the GIRM and Other Related Techniques