Loss of coolant accident analyses on Tehran research reactor by RELAP5/MOD3.2 code

In this paper, a loss of coolant accident (LOCA) in Tehran research reactor (TRR) is analyzed. The following procedure consists of three major parts. First, a RELAP5 nodalization of the core and the most important components of the primarily cooling system are developed and steady state condition is simulated and compared with experimental data [SAR for TRR, October 2002. Safety analysis report for Tehran research reactor. Nuclear Research Center of the Atomic Energy Organization of Iran, Tehran] to validate the nodalization. Then, two large break points are selected for design basis accident analyses. Finally, two main loss of coolant accidents are simulated and developed to analyze LOCA in TRR. It can be concluded that TRR is safe against the LOCA. And also RELAP5/MOD3.2 code can simulate research reactors at operating conditions well but it seems that this code cannot simulates large transient phases of the research reactors accurately as steady state condition specially in low pressure two phase mixtures (water and air).