Optimization of IEA-R1 reactor core parameters using the particle swarm algorithm

Abstract

This work aims on the development of a FORTRAN 90 code to solve the Loading Pattern Optimization Problem (LPOP) in the IEA-R1 research reactor at the Nuclear and Energy Research Institute (IPEN/CNEN-SP) in São Paulo, Brazil. The code integrates the Particle Swarm Optimization (PSO) method, with the current reactor calculation methodology. The objective function seeks to maximize the effective multiplication factor (keff), minimize the peak power factor (PPF), and achieve the most uniform neutron flux distribution possible. A comparison with the parameters of the reactor’s current configuration, and the code successfully finds solutions meeting the standard problem requirements. The new configuration enhances peak power (6.93%) and variance (9.62%), slightly increases neutron flux (0.48%), and marginally reduces in keff (0.45%). Additionally, it lowers the maximum fuel cladding temperature (0.7%), contributing to reactor safety.