Criticality Search of an Accelerator Driven System Using the ANET Code

Abstract
One of the most important safety parameters taken into consideration during the design and actual operation of a nuclear reactor is its control rods adjustment to reach criticality. Concerning the conventional nuclear systems, the specification of their rods’ position through the utilization of neutronics codes, deterministic or stochastic, is considered nowadays trivial. However, innovative nuclear reactor concepts such as the Accelerator Driven Systems require sophisticated simulation capabilities of the stochastic neutronics codes since they combine high energy physics, for the spallation-produced neutrons, with classical nuclear technology. ANET (Advanced Neutronics with Evolution and Thermal hydraulic feedback) is an under development stochastic neutronics code, able to cover the broad neutron energy spectrum involved in ADS systems and therefore capable of simulating conventional and hybrid nuclear reactors and calculating important reactor parameters. In this work, ANETS’s reliability to calculate the effective multiplication factor for three core configurations containing control rods of the Kyoto University Critical Assembly, an operating ADS, is examined. The ANET results successfully compare with results produced by well-established stochastic codes such as MCNP6.1.