Study of a low Mach nuclear core model for two-phase flows with phase transition I: stiffened gas law

Manuel Bernard (1) , Stéphane Dellacherie (2) , Gloria Faccanoni (3) , Bérénice Grec (4) , Yohan Penel (5, 6)

1 IFPEN - IFP Energies nouvelles
2 CEA-DES (ex-DEN) - CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire)
3 IMATH - Institut de Mathématiques de Toulon - EA 2134
4 MAP5 - UMR 8145 - Mathématiques Appliquées Paris 5
5 LJLL - Laboratoire Jacques-Louis Lions
6 CETMEF - Centre d'Études Techniques Maritimes et Fluviales

In this paper, we are interested in modelling the flow of the coolant (water) in a nuclear reactor core. To this end, we use a monodimensional low Mach number model coupled to the stiffened gas law. We take into account potential phase transitions by a single equation of state which describes both pure and mixture phases. In some particular cases, we give analytical steady and/or unsteady solutions which provide qualitative information about the flow. In the second part of the paper, we introduce two variants of a numerical scheme based on the method of characteristics to simulate this model. We study and verify numerically the properties of these schemes. We finally present numerical simulations of a loss of flow accident (LOFA) induced by a coolant pump trip event.

Domaines: Equations aux dérivées partielles [math.AP]; Analyse numérique [math.NA]

Manuel Bernard, Stéphane Dellacherie, Gloria Faccanoni, Bérénice Grec, Yohan Penel. Study of a low Mach nuclear core model for two-phase flows with phase transition I: stiffened gas law. 2012. ⟨hal-00747616v1⟩