A Coupled Calculation Suite for Atucha II Operational Transients Analysis

• Published in: Science and technology of nuclear installations 2011-01, Vol.2011 (2011), p.1-12
• Main Authors: Schivo, Miguel, Mazzantini, Oscar Alberto, Di Césare, Julián, Garbero, Ricardo, Rivero, Matías, Theler, Germán
• Format: Article
• Language: English
• ISSN: 1687-6075; 1687-6083
• DOI: 10.1155/2011/785304

While more than a decade ago reactor and thermal hydraulic calculations were tedious and often needed a lot of approximations and simplifications that forced the designers to take a very conservative approach, computational resources available nowadays allow engineers to cope with increasingly complex problems in a reasonable time. The use of best-estimate calculations provides tools to justify convenient engineering margins, reduces costs, and maximises economic benefits. In this direction, a suite of coupled best-estimate specific calculation codes was developed to analyse the behaviour of the Atucha II nuclear power plant in Argentina. The developed tool includes three-dimensional spatial neutron kinetics, a channel-level model of the core thermal hydraulics with subcooled boiling correlations, a one-dimensional model of the primary and secondary circuits including pumps, steam generators, heat exchangers, and the turbine with all their associated control loops, and a complete simulation of the reactor control, limitation, and protection system working in closed-loop conditions as a faithful representation of the real power plant. In the present paper, a description of the coupling scheme between the codes involved is given, and some examples of their application to Atucha II are shown.