RELAP5 code theoretical simulation of the experiment of natural circulation STAR

Abstract

Studies have been carried out on nuclear reactors with safety characteristics that do not depend on external intervention by operators or even on an external energy source. In this type of reactors, cooling is carried out by natural circulation, both during normal operation and during shutdown. For this reason, the STAR experiment was built in the IEA-R1 research reactor installed at the Institute for Energy and Nuclear Research (IPEN) – Brazil, with the aim of simulating experiments with the RELAP5 code in order to validate its models in two scenarios: total and partial emptying of the STAR. The results obtained with the RELAP5 code were compared to the experimental ones for the two proposed scenarios. These results showed that the mathematical correlations contained in RELAP5 are capable of reliably and safely reproducing the phenomenology of natural circulation in nuclear reactors.