Molten Core - Concrete Interactions in Nuclear Accidents

Theory and Design of an Experimental Facility

Research output: Book/ReportReportProfessional

3 Citations (Scopus)

Abstract

In a hypothetical severe accident in a nuclear power plant, the molten core of the reactor may flow onto the concrete floor of containment building. This would cause a molten core - concrete interaction (MCCI), in which the heat transfer from the hot melt to the concrete would cause melting of the concrete. In assessing the safety of nuclear reactors, it is important to know the consequences of such an interaction. As background to the subject, this publication includes a description of the core melt stabilization concept of the European Pressurized water Reactor (EPR), which is being built in Olkiluoto in Finland. The publication includes a description of the basic theory of the interaction and the process of spalling or cracking of concrete when it is heated rapidly. A literature survey and some calculations of the physical properties of concrete and corium-concrete mixtures at high temperatures have been conducted. In addition, an equation is derived for conservative calculation of the maximum possible concrete ablation depth. The publication also includes a literature survey of experimental research on the subject of the MCCI and discussion of the results and deficiencies of the experiments. The main result of this work is the general design of an experimental facility to examine the interaction of molten metals and concrete. The main objective of the experiments is to assess the probability of spalling, or cracking, of concrete under pouring of molten material. A program of five experiments has been designed, and pre-test calculations of the experiments have been conducted with MELCOR 1.8.5 accident analysis program and conservative analytic calculations.
Original languageEnglish
Place of PublicationEspoo
PublisherVTT Technical Research Centre of Finland
Number of pages88
ISBN (Electronic)951-38-6744-7
ISBN (Print)951-38-6743-9
Publication statusPublished - 2005
MoE publication typeNot Eligible

Publication series

NameVTT Tiedotteita - Research Notes
PublisherVTT
No.2311
ISSN (Print)1235-0605
ISSN (Electronic)1455-0865

Fingerprint

Molten materials
Accidents
Concretes
Spalling
Experiments
Concrete mixtures
Pressurized water reactors
Nuclear reactors
Ablation
Liquid metals
Concrete construction
Nuclear power plants
Melting
Stabilization
Physical properties
Heat transfer

Keywords

  • nuclear power plants
  • nuclear safety
  • reactor core
  • meltdown
  • concrete structures
  • containment buildings
  • spalling
  • cracking
  • simulation
  • MELCOR

Cite this

Sevón, T. (2005). Molten Core - Concrete Interactions in Nuclear Accidents: Theory and Design of an Experimental Facility. Espoo: VTT Technical Research Centre of Finland. VTT Tiedotteita - Meddelanden - Research Notes, No. 2311
Sevón, Tuomo. / Molten Core - Concrete Interactions in Nuclear Accidents : Theory and Design of an Experimental Facility. Espoo : VTT Technical Research Centre of Finland, 2005. 88 p. (VTT Tiedotteita - Meddelanden - Research Notes; No. 2311).
@book{1c8f18986d4d4042b779033cecc138a9,
title = "Molten Core - Concrete Interactions in Nuclear Accidents: Theory and Design of an Experimental Facility",
abstract = "In a hypothetical severe accident in a nuclear power plant, the molten core of the reactor may flow onto the concrete floor of containment building. This would cause a molten core - concrete interaction (MCCI), in which the heat transfer from the hot melt to the concrete would cause melting of the concrete. In assessing the safety of nuclear reactors, it is important to know the consequences of such an interaction. As background to the subject, this publication includes a description of the core melt stabilization concept of the European Pressurized water Reactor (EPR), which is being built in Olkiluoto in Finland. The publication includes a description of the basic theory of the interaction and the process of spalling or cracking of concrete when it is heated rapidly. A literature survey and some calculations of the physical properties of concrete and corium-concrete mixtures at high temperatures have been conducted. In addition, an equation is derived for conservative calculation of the maximum possible concrete ablation depth. The publication also includes a literature survey of experimental research on the subject of the MCCI and discussion of the results and deficiencies of the experiments. The main result of this work is the general design of an experimental facility to examine the interaction of molten metals and concrete. The main objective of the experiments is to assess the probability of spalling, or cracking, of concrete under pouring of molten material. A program of five experiments has been designed, and pre-test calculations of the experiments have been conducted with MELCOR 1.8.5 accident analysis program and conservative analytic calculations.",
keywords = "nuclear power plants, nuclear safety, reactor core, meltdown, concrete structures, containment buildings, spalling, cracking, simulation, MELCOR",
author = "Tuomo Sev{\'o}n",
note = "Project code: 12S-SAAAN1MMCE",
year = "2005",
language = "English",
isbn = "951-38-6743-9",
series = "VTT Tiedotteita - Research Notes",
publisher = "VTT Technical Research Centre of Finland",
number = "2311",
address = "Finland",

}

Sevón, T 2005, Molten Core - Concrete Interactions in Nuclear Accidents: Theory and Design of an Experimental Facility. VTT Tiedotteita - Meddelanden - Research Notes, no. 2311, VTT Technical Research Centre of Finland, Espoo.

Molten Core - Concrete Interactions in Nuclear Accidents : Theory and Design of an Experimental Facility. / Sevón, Tuomo.

Espoo : VTT Technical Research Centre of Finland, 2005. 88 p. (VTT Tiedotteita - Meddelanden - Research Notes; No. 2311).

Research output: Book/ReportReportProfessional

TY - BOOK

T1 - Molten Core - Concrete Interactions in Nuclear Accidents

T2 - Theory and Design of an Experimental Facility

AU - Sevón, Tuomo

N1 - Project code: 12S-SAAAN1MMCE

PY - 2005

Y1 - 2005

N2 - In a hypothetical severe accident in a nuclear power plant, the molten core of the reactor may flow onto the concrete floor of containment building. This would cause a molten core - concrete interaction (MCCI), in which the heat transfer from the hot melt to the concrete would cause melting of the concrete. In assessing the safety of nuclear reactors, it is important to know the consequences of such an interaction. As background to the subject, this publication includes a description of the core melt stabilization concept of the European Pressurized water Reactor (EPR), which is being built in Olkiluoto in Finland. The publication includes a description of the basic theory of the interaction and the process of spalling or cracking of concrete when it is heated rapidly. A literature survey and some calculations of the physical properties of concrete and corium-concrete mixtures at high temperatures have been conducted. In addition, an equation is derived for conservative calculation of the maximum possible concrete ablation depth. The publication also includes a literature survey of experimental research on the subject of the MCCI and discussion of the results and deficiencies of the experiments. The main result of this work is the general design of an experimental facility to examine the interaction of molten metals and concrete. The main objective of the experiments is to assess the probability of spalling, or cracking, of concrete under pouring of molten material. A program of five experiments has been designed, and pre-test calculations of the experiments have been conducted with MELCOR 1.8.5 accident analysis program and conservative analytic calculations.

AB - In a hypothetical severe accident in a nuclear power plant, the molten core of the reactor may flow onto the concrete floor of containment building. This would cause a molten core - concrete interaction (MCCI), in which the heat transfer from the hot melt to the concrete would cause melting of the concrete. In assessing the safety of nuclear reactors, it is important to know the consequences of such an interaction. As background to the subject, this publication includes a description of the core melt stabilization concept of the European Pressurized water Reactor (EPR), which is being built in Olkiluoto in Finland. The publication includes a description of the basic theory of the interaction and the process of spalling or cracking of concrete when it is heated rapidly. A literature survey and some calculations of the physical properties of concrete and corium-concrete mixtures at high temperatures have been conducted. In addition, an equation is derived for conservative calculation of the maximum possible concrete ablation depth. The publication also includes a literature survey of experimental research on the subject of the MCCI and discussion of the results and deficiencies of the experiments. The main result of this work is the general design of an experimental facility to examine the interaction of molten metals and concrete. The main objective of the experiments is to assess the probability of spalling, or cracking, of concrete under pouring of molten material. A program of five experiments has been designed, and pre-test calculations of the experiments have been conducted with MELCOR 1.8.5 accident analysis program and conservative analytic calculations.

KW - nuclear power plants

KW - nuclear safety

KW - reactor core

KW - meltdown

KW - concrete structures

KW - containment buildings

KW - spalling

KW - cracking

KW - simulation

KW - MELCOR

M3 - Report

SN - 951-38-6743-9

T3 - VTT Tiedotteita - Research Notes

BT - Molten Core - Concrete Interactions in Nuclear Accidents

PB - VTT Technical Research Centre of Finland

CY - Espoo

ER -

Sevón T. Molten Core - Concrete Interactions in Nuclear Accidents: Theory and Design of an Experimental Facility. Espoo: VTT Technical Research Centre of Finland, 2005. 88 p. (VTT Tiedotteita - Meddelanden - Research Notes; No. 2311).