Study of reactor criticality and kinetics calculation methods based on Geant4

Geant4 is a Monte Carlo simulation program toolkit based on C++ object-oriented technique. The toolkit can simulate various interactions between particles and medium materials and has been widely applied in high energy physics, accelerator physics, etc. However, because of the lack of critical source function, Geant4 cannot be used directly in reactor physics. Using physics models and particle tracking and control functions provided by Geant4, we implemented criticality calculation in two ways and developed Geant4-based static reactor simulation code G4-RSM and dynamic reactor simulation code G4-RDM. Both codes can be used for criticality simulation and the relative errors are within 5% compared with MCNP. Except for criticality simulation, G4-RDM can be used to simulate neutron characteristics in reactor accident conditions.