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

• DOI: 10.1016/j.nucengdes.2021.111147
• Publication Date: 2021-04-05T23:44:09Z
• Authors: A. Lecoanet; F. Payot; C. Journeau; N. Rimbert; M. Gradeck
• Keywords: Core-catcher; Sodium fast reactor; [SPI] Engineering Sciences [physics]; [PHYS.MECA.THER] Physics [physics]/Mechanics [physics]/Thermics [physics.class-ph]; [SPI.GPROC] Engineering Sciences [physics]/Chemical and Process Engineering; [SPI.FLUID]Engineering Sciences [physics]/Reactive fluid environment; Liquid jet; [SPI.FLUID] Engineering Sciences [physics]/Reactive fluid environment; Ablation; 01 natural sciences; 7. Clean energy; Corium-structure interaction; 0104 chemical sciences; [SPI]Engineering Sciences [physics]; Pool effect; [PHYS.MECA.THER]Physics [physics]/Mechanics [physics]/Thermics [physics.class-ph]; [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering; [PHYS.MECA.MEFL] Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph]; [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph]

Abstract In the scope of safety studies for future sodium cooled fast reactors (SFR), the use of discharge tubes and in-vessel core-catcher are foreseen for severe accident mitigation. During relocation of corium onto the core-catcher, complex thermal hydraulics phenomena can occur. This work focuses on the ablation of the core-catcher by the jet of corium. For that purpose, as experiments using corium and Na are difficult to achieve, we performed experiments using simulant materials: water jet on transparent ice. Transparent ice allows for ablation cavity real-time recording. Two main regimes were identified: a film flowing regime and a pool regime. We also studied the influence of temperature (30, 50, 70 °C) and velocity ( 1 , 2.5 , 5 , 7.5 , 10 m / s ) of the jet. Comparison with existing data have been done and finally, a scaling law in the first regime, for which the ablation rate is constant, has been found.