Cladding oxidation during air ingress. Part I: Experiments on air ingress

Experimental and modelling results of the QUENCH-18 bundle experiment on air ingress, cladding melting and aerosol release

“…Due to air ingress as a potential risk in low probability situations of severe accidents in nuclear power plants (Powers, 2000) or accidents in spent fuel pools (Burns et al, 2014), also other research centers have performed bundle tests on air ingress with bundle geometries other than in the QUENCH facility (Stuckert et al, 2016). In addition, numerous separate-effect tests conducted at KIT and elsewhere have demonstrated the strong effect of nitrogen on the oxidation kinetics of Zr alloys (Duriez et al, 2013;Steinbrück, 2009Steinbrück, , 2014Steinbrück and Bottcher, 2011;Steinbrück and Schaffer, 2016;Steinbrück et al, 2017).…”

Study on loss-of-cooling and loss-of-coolant accidents in spent fuel pool (confirmation of fuel temperature calculation function with oxidation reaction in the SAMPSON code)

“…Program mock-up test results showed that cladding of fuel assemblies burned violently in air, before finally breaking down (Lindgren and Durbin, 2007;Lindgren and Durbin, 2008). Joint European tests simulating accidental air ingress to the reactor vessel showed that oxidation of fuel cladding was promoted by air ingress, causing severe damage to fuel assemblies (Steinbrück, et al, 2006;Stuckert, et al, 2016;Beuzet, et al, 2016).…”

“…Such oxidation models were previously developed at the Argonne National Laboratory (ANL) (Natesan and Soppet, 2004) and L'institut de Radioprotection et de Sûreté Nucléaire (IRSN) (Coindreau, et al, 2010). These were integrated in the available analysis codes, and utilized in simulation of mock-up SFP accident experiments for code validation work (Lindgren and Durbin, 2007;Beuzet, et al, 2011;Beuzet, et al, 2016;Stuckert, et al, 2016). SAMPSON is a code included in the IMPACT code system which was developed through a 10-year project under sponsorship from the Japanese Ministry of Economy, Trade and Industry (Ujita, et al, 1999a).…”

Investigation of Zircaloy-2 oxidation model for SFP accident analysis

“…Mock-up fuel bundle tests were conducted in assumption of air inlet for reactor pressure vessel which would occur in occasion of piping rupture in NPP during a severe accident. They reported that the cladding oxidation behavior was much more intense in steam/air mixture or in dry air compared to the oxidation in steam [6][7][8].…”

“…The Argonne National Laboratory (ANL) in US and the Institut de Radioprotection et de Sûreté Nucléaire (IRSN) in France have proposed oxidation models for cladding in air environment [9,19]. In addition, simulations using severe accident codes which were modified by introducing these oxidation models have been conducted to calculate the oxidation behavior of mock-up fuel bundles in heating tests in air environment [3,8,[20][21]. These oxidation models were constructed for claddings made of alloys such as Zircaloy-4 (Zry4), ZIRLO T M , and M5 ® , while there were only few reports on the oxidation behavior of Zircaloy-2 (Zry2) in air, even though this alloy is widely utilized in BWRs [22,23].…”