Analyses Of The Spatial And Spectral Neutron Distribution Of Various Conceptual Core Designs With The Aim Of Optimizing The Safari-1 Research Reactor

The SAFARI-1 research reactor at Pelindaba is a 45 year old 20 MW tank-in-pool type material testing reactor, and is expected to reach the end of its operating life between 2020 and 2030. The purpose of this study is to investigate various inhomogeneous neutron distributions within the core, arising from different core layouts of the SAFARI-1 reactor, which nonetheless still achieve efficiency in the operation for various design purposes, but with a lower power output. The spatial and energy neutron distribution is one of the most important parameters in the characterization of such an alternative core layout. This neutron distribution is a result of basic physics processes such as particle matter interactions, nuclear reactions, material properties, the effect of temperature and the time evolution of the system. A SAFARI-1 reference core, obtained through an equilibrium cycle calculation, is used to generate a set of safety and utilization targets against which alternative designs are measured. Alternative core layouts were developed by using a parametric study to determine the size and power level of potential candidate conceptual cores while adhering to the safety and utilization requirements. Results indicate that an alternative core with a power of 17 MW can achieve similar performance results as the current 20 MW SAFARI-1 design, by simply rearranging components in the core.