Montreal Nuclear Services
Develop, test and document the CATHENA moderator system thermalhydraulics model for Gentilly-2, and perform deterministic safety analyses of moderator system events.
Moderator events were not part of Gentilly-2 Safety Report prior to refurbishment. A CATHENA moderator system model was developed as part of the refurbishment project.
The work consisted of developing, testing and documenting the CATHENA moderator system thermalhydraulics model. The model was compared against plant data at 100%FP and during power maneuvers.
The CATHENA model was used to perform deterministic safety analysis of the moderator cooling system (loss of flow, loss of heat sink, loss of inventory and heat exchanger tube rupture). The improvement in safety margin, due to the addition of new trip parameters, was assessed.
Public doses were calculated for loss of moderator inventory inside and outside of the reactor building. Recommendations were made to add tritium detectors in the service building.The work was contracted by Hydro-Québec to AECL (Atomic Energy of Canada Ltd). Gilles Sabourin assumed the technical supervision.
NOTE: This work was performed / lead by MNS personnel during their previous employment