CATHARE 2 V2.5_2: A single version for various applications

Abstract This paper presents the new capabilities of CATHARE 2 as a multi-purpose multi-reactor concept system code. The CATHARE 2 code was originally devoted to best estimate calculations of thermal–hydraulic transients in Water-Cooled Reactors such as PWR, VVER or BWR. Recently, in the framework of the Generation IV International Forum, CEA launched several feasibility studies of future advanced reactor concepts including Gas-Cooled Reactors, Sodium-Cooled Fast-Breeder Reactors, Supercritical Water-Cooled Reactors. The 2-fluid model with non-condensable gases transport equations was first easily extended to Gas-Cooled Reactor applications with very few modifications. At the same time CEA seized opportunity to use CATHARE 2 to perform studies for non-nuclear industrial applications such as cryogenic rocket engines. New capabilities were implemented allowing passage from supercritical pressure to subcritical conditions and these features were then easily applied to Supercritical Water-Cooled Reactors. New developments were also necessary to extend the code to Sodium-Cooled Reactors. CATHARE 2 can now describe several circuits with various fluids either in single-phase gas or liquid, or in two-fluid conditions possibly with noncondensable gases, which allows simulating any kind of reactor concept and any kind of accidental transient. The development method for the extension to new fluids is presented with an overview of the most striking functional and modelling features that have been implemented in the new CATHARE 2 V2.5_2 version to be released mid-2009 for industrial applications.