Publication detail

Assessment of the design of injection and depressurization system dedicated for severe accidents for VVER440

BALÁŽ, J.

Original Title

Assessment of the design of injection and depressurization system dedicated for severe accidents for VVER440

Type

conference proceedings

Language

English

Original Abstract

Severe accident mitigation measures are gradually implemented at Slovak nuclear power plants. Coolant injection, into primary circuit and depressurization system of primary circuit were included within the scope of measures to cope with severe accidents. One of the crucial issues of these systems is to ensure successful quenching of the core during water delivery in severe accident conditions. System is designed to deliver water into primary circuit, spent fuel pool and also to containment spray system. Water delivery into primary circuit, capable of quenching the core, has to be considered in connection with design of the primary circuit depressurization system for severe accident conditions in order to maintain such low pressure in primary circuit that is necessary to keep required water flow into primary circuit. Conservative approach was used for design of both (depressurization system and system for water delivery into primary circuit), but best estimate analyses were executed to prove their interrelation and functionality. Analyses were focused especially on the capability of systems to cooperate and keep required flow rate of coolant into the core, during intensive hydrogen and steam production, while the pressure in primary circuit is maintained appropriately low. Best estimate analyses were carried out to prove capabilities of the system and to verify overall hydrogen production, time of water level recovery and extent of core degradation, while the initial conditions vary. Analyses imply strong influence of depressurization process on total hydrogen production and ability of depressurization to significantly contribute to cool down of the core. All the analyses were carried out using MELCOR 1.8.5 RK (quench model implemented).

Keywords

Depressurization, Hydrogen production, Quenching, Cladding, Primary circuit, Reactor Pressure Vessel, Core

Authors

BALÁŽ, J.

Released

23. 11. 2011

Publisher

Karlsruhe Institute of Technology

Location

Karlsruhe Institute of Technology Campus North Heman-von-Helmholtz-platz 1 76344 Eggenstein-Leopoldshafen

ISBN

978-3-923704-77-4

Book

Proceedings of the 17th International QUENCH workshop

Edition

CD

Pages from

1

Pages to

22

Pages count

20

URL

http://quench.forschung.kit.edu/

BibTex

@proceedings{BUT88675,
  editor="Jozef {Baláž} and Juraj {Jančovič}",
  title="Assessment of the design of injection and depressurization system dedicated for severe accidents for VVER440",
  year="2011",
  series="CD",
  pages="1--22",
  publisher="Karlsruhe Institute of Technology",
  address="Karlsruhe Institute of Technology Campus North Heman-von-Helmholtz-platz 1 76344 Eggenstein-Leopoldshafen",
  isbn="978-3-923704-77-4",
  url="http://quench.forschung.kit.edu/"
}