Validation of the COMET Bottom-Flooding Core-Catcher with Prototypic Corium

Journeau, Christophe; Alsmeyer, Hans

Title: Validation of the COMET Bottom-Flooding Core-Catcher with Prototypic Corium

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Abstract

The COMET concept is developed to cool an ex-vessel corium melt, in case of a hypothetical severe accident leading to vessel melt-through, by passive injection of coolant water to the bottom of the melt. An advanced version of this concept (CometPCA) uses a porous concrete layer from which the water is supplied to the melt predominantly through a group of porous channels. The concept was designed to be largely independent of different accident scenarios. It could be applied to both current and future reactors. FZK has successfully performed in Germany a series of large-scale experiments with simulant corium melts. An important step in validating the concept is the use of a reactor typical oxide melt (UO{sub 2} + ZrO{sub 2} + molten concrete). A unit cell of the cooling device was used in the VULCANO facility in a 20 cm diameter, 60 cm high crucible with about 40 kg corium melt. The melt has been generated and poured from the VULCANO plasma arc furnace into the COMET cooling device at an initial temperature above 2000 K. It was internally heated by sustained induction power (varying between 10 and 30 kW) until complete cooling was achieved. The initial condition for onsetmore »« less

Authors:

Journeau, Christophe ^[1]; Alsmeyer, Hans ^[2]

CEA Cadarache, Severe Accident Mastering experimental Laboratory (DEN/DTN/STRI/LMA), 13108 St Paul lez Durance (France)
Forschungszentrum Karlsruhe, IKET, Karlsruhe (Germany)

Publication Date:: Sat Jul 01 00:00:00 EDT 2006

Research Org.:: American Nuclear Society, 555 North Kensington Avenue, La Grange Park, IL 60526 (United States)

OSTI Identifier:: 21021013

Resource Type:: Conference

Resource Relation:: Conference: 2006 International congress on advances in nuclear power plants - ICAPP'06, Reno - Nevada (United States), 4-8 Jun 2006; Other Information: Country of input: France; 10 refs; Related Information: In: Proceedings of the 2006 international congress on advances in nuclear power plants - ICAPP'06, 2734 pages.

Country of Publication:: United States

Language:: English

Subject:: 21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS; ARC FURNACES; CONCRETES; CONTAINERS; COOLANTS; COOLING; CORE CATCHERS; CORIUM; CRUCIBLES; EQUIPMENT; EVAPORATION; LAYERS; POROUS MATERIALS; REACTOR ACCIDENTS; URANIUM DIOXIDE; VALIDATION; WATER; WATER SUPPLY; ZIRCONIUM OXIDES

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                    Journeau, Christophe, and Alsmeyer, Hans. Validation of the COMET Bottom-Flooding Core-Catcher with Prototypic Corium.  United States: N. p., 2006. 
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                    Journeau, Christophe, & Alsmeyer, Hans. Validation of the COMET Bottom-Flooding Core-Catcher with Prototypic Corium.  United States.

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                    Journeau, Christophe, and Alsmeyer, Hans. 2006.  
        "Validation of the COMET Bottom-Flooding Core-Catcher with Prototypic Corium".  United States.

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@article{osti_21021013,

  title        = {Validation of the COMET Bottom-Flooding Core-Catcher with Prototypic Corium},

  author       = {Journeau, Christophe and Alsmeyer, Hans},

  abstractNote = {The COMET concept is developed to cool an ex-vessel corium melt, in case of a hypothetical severe accident leading to vessel melt-through, by passive injection of coolant water to the bottom of the melt. An advanced version of this concept (CometPCA) uses a porous concrete layer from which the water is supplied to the melt predominantly through a group of porous channels. The concept was designed to be largely independent of different accident scenarios. It could be applied to both current and future reactors. FZK has successfully performed in Germany a series of large-scale experiments with simulant corium melts. An important step in validating the concept is the use of a reactor typical oxide melt (UO{sub 2} + ZrO{sub 2} + molten concrete). A unit cell of the cooling device was used in the VULCANO facility in a 20 cm diameter, 60 cm high crucible with about 40 kg corium melt. The melt has been generated and poured from the VULCANO plasma arc furnace into the COMET cooling device at an initial temperature above 2000 K. It was internally heated by sustained induction power (varying between 10 and 30 kW) until complete cooling was achieved. The initial condition for onset of passive flooding was established about 1 minute after the pouring, when the top layer of sacrificial concrete was eroded and the passive water injection started. The next important process originating from fast evaporation of the injected coolant water, was the inherent transfer of the corium melt into a permeable porous oxide melt layer allowing a permanent intimate contact of the solidifying melt with the steam/water flow from below. About 17 kg of water was vaporized and subsequently condensed during the course of the experiment, while water supply from the bottom continued, flooded and eventually covered the porously solidified corium melt. The melt was safely arrested, solidified and quenched within a period of less than 20 minutes without any energetic event, as expected from previous experiments with simulant melts. Post-test analysis has started to characterize the porosity of the solidified melt and to provide further useful insights. (authors)},

  doi          = {},

  url          = {https://www.osti.gov/biblio/21021013},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {Sat Jul 01 00:00:00 EDT 2006},

  month        = {Sat Jul 01 00:00:00 EDT 2006}

}

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