RELAP5 Experiences and Applications for Heavy Water Reactor Technology at Nine

Abstract

The present paper summarizes the experiences and the applications of RELAP5 code for performing thermal-hydraulics analysis in heavy water reactor technology. In particular three analyses are discussed in detail:

• The safety analysis carried out to support the licensing process of the Atucha-2 Nuclear Power Plant in Argentina;
• The transient analysis performed to simulate the Loss-Of-Flow accident in Darlington Nuclear Power Plant;
• The simulation of the core of OPAL Research Reactor in Australia to evaluate the consequence of a possible increase of the analytical limit for the Reactor Protection System overpower trip.

Additionally to the performed analyses, the paper provides insights in relation the methodology adopted for qualifying a system thermal-hydraulic code calculation, and in particular in respect to the demonstration of the geometrical fidelity, demonstration of the steady state achievement and the qualification at on-transient level.