K.E. Chesson and W.S. Charlton,
"A Brief Sensitivity Analysis for the GIRM and Other Related Techniques using a One-Group Cross Section Library for Graphite-Moderated Reactors,"
Annual Meeting of the Institute for Nuclear Materials Management
, July 8-12, 2007, Tucson, AZ.
Several methods have been developed previously for estimating
cumulative energy production and plutonium production from
graphite-moderated reactors. These methods generally fall into the
category of nuclear archaeology. The Graphite Isotope Ratio Method
(GIRM) is one well-known technique of this type. 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 fuel 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 oxide (magnox) 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 brief sensitivity analysis conducted in this study
assessed various input parameters including 235U and 238U 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 as the level of
uncertainty that may be found in the system results.
Associated Project(s):Sensitivity Analysis for the GIRM and Other Related Techniques