open access

https://hdl.handle.net/2115/74434

Uncertainty quantification of neutron multiplication factors of light water reactor fuels during depletion

英語

uncertainty quantification

2018-05-29

Taylor & Francis

Journal of nuclear science and technology

55(9)

1043-1053

Nuclear data-induced uncertainties of infinite neutron multiplication factors (k) during fuel depletion are quantified in a single cell and a 3x3 multi-cell including burnable absorbers. Uncertainties of reaction cross sections, fission yields, decay half-lives and decay branching ratios provided in the JENDL libraries are taken into account. Hundred percent uncertainties are assumed to nuclear data to which uncertainty information are not provided in JENDL. Uncertainties propagation calculations are carried out with the adjoint-based procedure, and required sensitivity profiles of k with respect to these nuclear data are efficiently calculated by the depletion perturbation theory. Covariance matrices for fission yields and decay data in a simplified burnup chain are successfully generated by the stochastic-based procedure. k uncertainties of about 0.6% during fuel depletion are obtained, and it is shown that actinoids reaction cross sections are dominant contributors. Nuclide-wise decomposition of the uncertainties and observation of component-wise sensitivity profiles provide physical interpretations. By virtue of the adjoint-based procedure, several parametric surveys are also conducted. Contributions of uncertainties in fission products (FPs) nuclides are quantified, and important nuclides and energy ranges are identified for further evaluation of nuclear data of FP nuclides. Effect of cooling period on k uncertainties is also discussed.

学術雑誌論文

Accepted Manuscript

This is an Accepted Manuscript of an article published by Taylor & Francis in Journal of Nuclear Science and Technology on 29 May 2018, available online: http://www.tandfonline.com/10.1080/00223131.2018.1467803.

0022-3131