Determination of criticality safety MCNP5 calculation bias by using different libraries of cross section data

Application of different cross section libraries and different versions of Monte Carlo code MCNP has an influence on the calculation results and therefore determination of criticality safety calculation bias forms part of improving accuracy of simulations using computational systems and codes. In this paper, criticality calculations results are presented for 21 problems coming from the International Handbook of Evaluated Criticality Benchmark Experiments (International Handbook, 2007). All of these problems are related to VVER-440 reactors because of their extensive use in Slovakia. Three libraries of cross section data were investigated:
• JEFF-3.1 General purpose library,
• ENDF/B-VII library,
• JENDL 4.0.Calculations were provided with MCNP5-1.40 and MCNP5-1.60 transport codes. Two cluster systems situated at our Institute were used. Main purpose of this analyses was the determination of the bias which should be used in further simulations.

► Determination of MCNP calculation bias for VVER-440.
► Three cross section libraries used.
► 21 Benchmark cases investigated.
► Three methods of production material cards for hydrogen bound in light water.
► Combined bias presented.