Study of the ablation consecutive to jet impingement on a meltable solid – Application to SFR core-catcher

Model for core catcher ablation and cavity shape in the film regime

“…However, because of back light illumination used in the experimental bench named HAnSoLO, a projection of the cavity shape is obtained. Therefore, the local increase in depth is not visible, and where it occurs, the cavity appears flat [9]. To summarize, in both cavity types, there is a stagnation zone, a boundary layer growth zone, a transition toward turbulence zone and a turbulent zone.…”

“…The jet may also more readily fragment prior to impact. Consequently, the thermal load of the jet on a solid surface is reduced if the jet passes liquid than if it passes through gas [9]. Furthermore, when the jet and the solid structure are of different nature or composition, the temperature of melting can be really different leading to a crust formation.…”

“…During the course of ablation, two regimes, which occur sequentially, have been identified [10,9,12]. First, the liquid spreads over the solid as a film during the "film regime".…”

“…This regime was first discovered by Saito et al [10] and will be referred to herein as the "pool regime". For more details on pool regime, the reader is referred to [9] for phenomenological analysis and to [12] for a first analytic model describing the transition between these two regimes. This study focuses on the progression of the film regime.…”

Validation of analysis models on relocation behavior of molten core materials in sodium-cooled fast reactors based on the melt discharge experiment

“…In case of a core disruptive accident (CDA) in a sodium-cooled fast reactor (SFR), it is important to ensure in-vessel retention which maintains and confines the damaged core material in the reactor vessel. Recently, molten jet impingements were discussed for the capability of a SFR's in vessel core catcher (Lecoanet, et al, 2021). However, such researches are limited to the sodium coolant system.…”