Evaluations of the Coolability Through the Inherent In-Vessel Gap Cooling in the LAVA Experiments
- Korea Advanced Energy Research Institute - KAERI, P.O.Box 105, Yuseong, Daejeon 305-353 (Korea, Republic of)
The analysis of the LAVA (Lower-plenum Arrested Vessel Attack) experimental results focused on gap formation and in-vessel gap cooling characteristics have been performed. In the LAVA experiment, Al{sub 2}O{sub 3}/Fe thermite melt (or Al{sub 2}O{sub 3} only) was used as a corium simulant with a 1/8 linear scale mock-up of the reactor vessel lower plenum. The experimental results address the non-adherence of the debris to the lower head vessel and the consequent gap formation in case there was an internal pressure load across the vessel. The thermal behaviors of the lower head vessel during the cooldown period were mainly affected by the heat removal characteristics through this gap, which were mainly determined by the possibilities of the water ingression into the gap. The possibility of heat removal through the gap in the LAVA experiments was confirmed from that the vessel cooled down with the conduction heat flux through the vessel by 70 to 470 kW/m{sup 2}. Also the quantitative evaluations of the in-vessel coolability using gap cooling model based on counter current flow limits (CCFL) have been performed for the LAVA experiments in parallel. It could be inferred from the analysis for the LAVA experiments that the vessel could effectively cooldown via heat removal through the gap cooling even if 2 mm thick gap should form between the interface of the melt and the vessel in the 30 kg of Al{sub 2}O{sub 3} melt tests. In the case of large melt mass of 70 kg of Al{sub 2}O{sub 3} melt, however, the infinite possibility of heat removal through a small size gap such as 1 to 2 mm thick couldn't be guaranteed due to the difficulties of water ingression through the gap into the lower head vessel bottom induced by the CCFL. Synthesized the experimental results and the analytical evaluations using the CCFL model, it could be found that the coolability through gap cooling was affected mainly by the melt composition and mass and also the gap thickness. (authors)
- Research Organization:
- The ASME Foundation, Inc., Three Park Avenue, New York, NY 10016-5990 (United States)
- OSTI ID:
- 21076279
- Resource Relation:
- Conference: ICONE-10: 10. international conference on nuclear engineering, Arlington - Virginia (United States), 14-18 Apr 2002; Other Information: Country of input: France
- Country of Publication:
- United States
- Language:
- English
Similar Records
An Experimental Study of Critical Heat Flux in Narrow Gap With Two-Dimensional Slices
Experiments on in-vessel melt coolability in the EC-FOREVER program