Effects of lateral separation of oxidic and metallic core debris on the BWR MK I containment drywell floor
Abstract
In evaluating core debris/concrete interactions for a BWR MK I containment design, it is common practice to assume that at reactor vessel breach, the core debris is homogeneous and of low viscosity, so that it flows through the pedestal doorway and spreads in a radially uniform fashion throughout the drywell floor. In a recent study performed by the NRC-sponsored Boiling Water Reactor Severe Accident Technology (BWRSAT) program at Oak Ridge National Laboratory, calculations indicate that at reactor vessel bottom head failure, the debris temperature is such that the debris metals (Zr, Fe, Ni, Cr) are completely molten while the oxides (UO/sub 2/, ZrO/sub 2/, FeO) are completely frozen. Thus, the frozen oxides are expected to remain within the reactor pedestal while the molten metals radially separate from the frozen oxides, flow through the reactor pedestal doorway, and spread over the annular region of the drywell floor between the pedestal and the containment shell. This paper assesses the impact on calculated debris gas releases and the production and release of fission product-laden aerosols for two different cases of debris distribution: uniform distribution and the laterally separated case of 95% oxides-5% metals inside the pedestal and 5% oxides-95% metals outside the pedestal.more »
- Authors:
- Publication Date:
- Research Org.:
- Oak Ridge National Lab., TN (USA)
- OSTI Identifier:
- 7156848
- Report Number(s):
- CONF-8610135-33
ON: DE87001833
- DOE Contract Number:
- AC05-84OR21400
- Resource Type:
- Conference
- Resource Relation:
- Conference: 14. water reactor safety information meeting, Gaithersburg, MD, USA, 27 Oct 1986; Other Information: Portions of this document are illegible in microfiche products
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 22 GENERAL STUDIES OF NUCLEAR REACTORS; 21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS; BWR TYPE REACTORS; CONTAINMENT SYSTEMS; CONCRETES; C CODES; CORIUM; EVALUATION; INTERACTIONS; M CODES; V CODES; BUILDING MATERIALS; COMPUTER CODES; CONTAINMENT; ENGINEERED SAFETY SYSTEMS; MATERIALS; REACTORS; WATER COOLED REACTORS; WATER MODERATED REACTORS; 220900* - Nuclear Reactor Technology- Reactor Safety; 210100 - Power Reactors, Nonbreeding, Light-Water Moderated, Boiling Water Cooled
Citation Formats
Hyman, C R, and Weber, C F. Effects of lateral separation of oxidic and metallic core debris on the BWR MK I containment drywell floor. United States: N. p., 1986.
Web.
Hyman, C R, & Weber, C F. Effects of lateral separation of oxidic and metallic core debris on the BWR MK I containment drywell floor. United States.
Hyman, C R, and Weber, C F. 1986.
"Effects of lateral separation of oxidic and metallic core debris on the BWR MK I containment drywell floor". United States. https://www.osti.gov/servlets/purl/7156848.
@article{osti_7156848,
title = {Effects of lateral separation of oxidic and metallic core debris on the BWR MK I containment drywell floor},
author = {Hyman, C R and Weber, C F},
abstractNote = {In evaluating core debris/concrete interactions for a BWR MK I containment design, it is common practice to assume that at reactor vessel breach, the core debris is homogeneous and of low viscosity, so that it flows through the pedestal doorway and spreads in a radially uniform fashion throughout the drywell floor. In a recent study performed by the NRC-sponsored Boiling Water Reactor Severe Accident Technology (BWRSAT) program at Oak Ridge National Laboratory, calculations indicate that at reactor vessel bottom head failure, the debris temperature is such that the debris metals (Zr, Fe, Ni, Cr) are completely molten while the oxides (UO/sub 2/, ZrO/sub 2/, FeO) are completely frozen. Thus, the frozen oxides are expected to remain within the reactor pedestal while the molten metals radially separate from the frozen oxides, flow through the reactor pedestal doorway, and spread over the annular region of the drywell floor between the pedestal and the containment shell. This paper assesses the impact on calculated debris gas releases and the production and release of fission product-laden aerosols for two different cases of debris distribution: uniform distribution and the laterally separated case of 95% oxides-5% metals inside the pedestal and 5% oxides-95% metals outside the pedestal. The computer codes used are CORCON-MOD2, MARCON 2.1B and VANESA.},
doi = {},
url = {https://www.osti.gov/biblio/7156848},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Wed Jan 01 00:00:00 EST 1986},
month = {Wed Jan 01 00:00:00 EST 1986}
}