Fission products and nuclear fuel behaviour under severe accident conditions part 1: Main lessons learnt from the first VERDON test

Fission products and nuclear fuel behaviour under severe accident conditions part 3: Speciation of fission products in the VERDON-1 sample

“…The results presented above are discussed in this section according to three main axes: (1) metallic precipitates evolution, (2) oxide phase evolution and (3) comparison with the first part of the article in terms of FP released fractions [11]. Again, the intermediate state sample composed of an irradiated fuel pellet in its original M5 cladding selected from the same UO 2 father rod as the VERDON-1 sample was used to complete the analysis of the results [12].…”

“…before the test. The VERDON-1 experimental circuit, the progress of the accidental thermalhydraulic sequence and the results in terms of FP release and fuel behavior are briefly summarized as it has been extensively discussed in two previous article [11], [12].…”

Fission products and nuclear fuel behaviour under severe accident conditions part 2: Fuel behaviour in the VERDON-1 sample

“…The experimental loop has been extensively described in [1], [7]- [12] so only the main characteristics are recalled in this section.…”

“…A special focus is made on the different chemical phases found into the fuel and a scenario explaining the evolution of the fuel during the test is proposed. The VERDON-1 experimental circuit and the progress of the accidental thermal-hydraulic sequence are briefly summarized as it has been extensively discussed in a first article [1].…”

Effect of molybdenum on the behaviour of caesium in uranium dioxide at high temperature

“…Under normal operating conditions, most of Cs remains in the UO2 matrix [1] and may accumulate at the pellet periphery or in the HBS zone [2,3]. Different accidental conditions were reproduced during semi-integral research programs like VERCORS, VERDON and VEGA [4][5][6][7]. These tests consisted in submitting irradiated nuclear fuel to high temperature (>2000°C) under different atmospheres and measuring the nature and quantity of released FPs.…”