%0 Conference Proceedings %T A pipe-model to assess the hydrodynamic effects of a blowdown in a 4-loop PWR %+ Service d'Etudes Mécaniques et Thermiques (SEMT) %+ EDF Labs %A Robbe, Marie-France %A Potapov, Serguei %Z Proceedings of the 8th International Conference on Nuclear Engineering (Icone8); Baltimore, USA, April 2-6 %< avec comité de lecture %@ 9780791835050 %( Proceedings of the 8th International Conference on Nuclear Engineering 2000, ICONE-8: 2 pts. Thermal hydraulicsVolume 6 de Proceedings of the 8th International Conference on Nuclear Engineering 2000, ICONE-8, International Conference on Nuclear Engineering presented at 8th International Conference on Nuclear Engineering, %B ICONE8 - 8th International Conference on Nuclear Engineering %C Baltimore, United States %Y ASME %P ICONE-8156 %8 2000-04-02 %D 2000 %K LOCA %K blowdown %K depressurization %K break %K hydrodynamic loads %K hydraulic circuit %K PWR %Z Engineering Sciences [physics]/Mechanics [physics.med-ph]/Structural mechanics [physics.class-ph]Conference papers %X During the first milliseconds of a Loss Of Coolant Accident in a PWR, a depressurization wave propagates from the break through the whole primary circuit and the reactor. Then the circuit empties progressively with a diphasic regime. The propagation delay of the depressurization wave causes local transient pressuredifferences between various zones of the reactor. The pressure differences around the core zone may damage the fuel assemblies and the core structures. Consequently, the reactor pressure map must be assessed during the blowdown phase. As the depressurization process is very dependent on the break conditions, it is important to model precisely the break hydrodynamic regime and to represent the complete primary circuit.This paper presents CASTEM-PLEXUS hydrodynamic calculations of the blowdown due to a LOCA, in the primary circuit of a four-loop-PWR. The hydraulic circuit isrepresented with a pipe model respecting the 3D component volumes and the average journey of the diphasic water. Specic laws complete the description for section changes and multi-pipe links. The hydraulic peculiarities (pumps, pressure losses and the break) are taken into account thanks to additional constitutive laws and bounding conditions. The initial conditions are those of the reactor nominal rating. The calculation describes the pressure transient coupled with diphasic water mass transfers, due to the break opening and the beginning of the circuit emptying. %G English %2 https://cea.hal.science/cea-04071507/document %2 https://cea.hal.science/cea-04071507/file/article_MFRobbe_Icone8_APRP_N4.pdf %L cea-04071507 %U https://cea.hal.science/cea-04071507 %~ CEA %~ DEN %~ DEN-SACLAY