The simulation the effect of reflector thickness on criticality using SCALE computer code on the plate-type fuel conversion design for Bandung Triga reactor.

One of the main components of a nuclear reactor is reflector. The function of the reflector is to reflect neutrons, so they return to the reactor core. The requirements needed for the reflector material are having a relatively high cross-section of neutron scattering, having a low absorption cross section. Graphite (C) is one element with a mass number 12. Graphite has a value of σand σs with a ratio of 1: 1000, suitable to the requirement of the reflector which must have a small value of σand large σs. Criticality simulation was carried out using the SCALE computer code for several levels of reflector (graphite) thickness using plate fuel elements in the TRIGA Bandung reactor core. The research purpose to study the effect of reflector thickness on the criticality value of the modified TRIGA Bandung reactor core using plate type fuel elements. This research uses the SCALE computer code, the components of the modeled TRIGA 2000 reactor are: plate fuel element, control element, reflector, reactor pool (water). Reactor criticality simulation has been carried out using SCALE 6.1. There are 4 control elements and 16 fuel elements inside the reactor core, reflector thickness variated. Starting without any reflector, until the thickness of the reflector 6 cm. The k-eff (fully up control rod) value improves with the improvement of the thickness of the reflector, especially from 0 cm to 3.5 cm, after that the k-eff value does not change, the effective thickness for the graphite reflector is 3.5 cm, value of k-eff is 1.032 (fully up control rod) and value of k-eff is 0.8467 (fully down control rod), and standard deviation value is 0.0018. [ABSTRACT FROM AUTHOR]