Faire avancer la sûreté nucléaire

La Recherchev2


Inherent boron dilution safety issue in the French pressurized water reactor: CFD approach



Email :

Mot de passe :

E. Graffard, F. Goux,
14th International Conference on Nuclear Engineering (ICONE 14), Miami, Floride, USA, 17-20 juillet 2006,
Rapport DSR 133

Type de document > *Rapport/contribution à GT (papier ou CD-Rom), *Congrès/colloque

Mots clés > déboration, réacteurs à eau sous pression (REP)

Unité de recherche > IRSN/DSR/ST3C

Auteurs > GOUX Frédéric, GRAFFARD Estelle

Date de publication > 31/08/2006


Inherent boron dilution can occur in case of a Small Break LOCA when low borated water is mainly accumulated in the U-legs due to reflux boiling in the Steam Generator tubes after the loss of natural circulation. The restart of the natural circulation may lead to criticality because of the injection of these low borated slugs towards the core. To evaluate this potential risk, the boron concentration at the core inlet has to be known which makes necessary to estimate the mixing phenomena in the cold leg, in the downcomer and in the lower plenum: CFD calculations are required.
First of all the validation of CFX5 CFD code on the relevant phenomena of inherent boron dilution has been established (UPTF TRAM C3 test). Then, an application to the 900 MW French Pressurized Water Reactor series has been performed.