A review of history parameters in PWR core analysis

Ea. Szames (1) , D. Tomatis (1)

1 CEA-DES (ex-DEN) - CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire)

We present a review of the methodologies for history effect modelling with few-group cross sections for PWR fuel assemblies. Different depletion conditions with varying moderator density, fuel temperature and protracted control rod insertion are considered where the exposure history can show significant changes in the local isotopic inventory and in the neutron spectra.Cross sections are homogenized over a classical PWR-type $\text{UO}_2$ fuel assembly provided by the Burn-up Credit Criticality Benchmark NEA-6227 and condensed in two energy groups by the lattice code APOLLO2.8. The methodologies are analyzed in view of their capability to improve the error in microscopic and macroscopic cross sections, and the associated multiplication factor and the spectral index in the infinite homogeneous medium.

Mots clés: history effects; PWR; Cross section preparation; protracted control by mechanical shim

Domaines: Physique Nucléaire Expérimentale [nucl-ex]; Physique Nucléaire Théorique [nucl-th]

Ea. Szames, D. Tomatis. A review of history parameters in PWR core analysis. Annals of Nuclear Energy, 2018, ⟨10.1016/j.nucengdes.2019.03.012⟩. ⟨cea-02339996⟩