Interpretation of GEDEON-1 and GEDEON-2 gadolinium depletion experimental analysis with the DARWIN2.3 package

T. Nicol (1) , D. Bernard (1)

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

In the eighties a two phases experimental program, called GEDEON, was designed at CEA for the validation of gadolinium depletion calculation in a 13 x 13 LWR assembly (3.25% $^{235}$U enrichment). In the first experiment, gadolinium pins are enriched with 3.5% of $^{235}$U and contained 5% in mass of natural gadolinium. In the second experiment gadolinium support pins is made of depleted uranium (0.2% $^{235}$U) and contains 8% in mass of natural gadolinium. DARWIN is an evolution code package developed at CEA in corporation with industrial companies (EDF, Framatome, Orano) in order to compute physical quantities of radioactivity related to various application fields such as nuclear fuel cycle. This paper presents the first interpretation, with DARWIN2.3 package, of those two experiments in the aim of gadolinium depletion experimental validation of DARWIN. Interpretations are performed using the European evaluation file JEFF-3.1.1 and a 281 group energy mesh. Results show quite good agreements between calculation and measurements, in respect with experimental and calculation uncertainties, especially for $^{155}$Gd and $^{157}$Gd isotopes depletion.

Keywords: Gadolinium depletion; burnable poison; DARWIN

Domains: Nuclear Experiment [nucl-ex]; Nuclear Theory [nucl-th]

T. Nicol, D. Bernard. Interpretation of GEDEON-1 and GEDEON-2 gadolinium depletion experimental analysis with the DARWIN2.3 package. ICNC 2019 -11th International conference on Nuclear Criticality Safety, Sep 2019, Paris, France. ⟨cea-02614120⟩