VVER-1000 cross-section library generation for ORIGEN-II based on MCNP calculations

• The use of MCNP code to generate average one-group cross section library for ORIGIN-II.
• Simulation of the entire core of Bushehr Nuclear Power Plant (BNPP) in its operational first cycle.
• Validation of ORIGIN-II library for BNPP with the reference data.
• Availability of a new ORIGIN-II library for an in-core fuel management for the future cycles.

Most nuclear burnup, depletion and radioactive decay computational codes, such as ORIGEN-II, are geometry independent and so called point codes. Consequently, the effect of reactor geometry and other reactor conditions are compiled in their own cross-section library. For several types of reactor such as PWR or BWR, the cross-section libraries are provided for ORIGEN-II code, but for Bushehr nuclear reactor which is a VVER-1000 type reactor, such cross-section library does not exist in the code. In this study, attempts have been made to generate a cross-section library for VVER-1000 type reactor. In this study, attempts have been made to generate a cross-section library for VVER-1000 type reactor. In order to model the Bushehr Nuclear reactor (BNPP) core and generate a cross-section library suitable for ORIGEN-II calculations, MCNP Monte-Carlo code was used. The validation tests were carried out by comparing the burnup results of the new library with the burnup results obtained from MCNP calculations and burnup, depletion and radioactive decay reported in BNPP reference data.