Validation of PRESTO-II against measured aeroball traces in KKP2

The purpose of this paper is to present the latest results of comparisons of PRESTO-II calculations with actual aeroball flux traces in KKP-II for the complex first core loading, including 16x16-20 assemblies of 3 different enrichments, part length burnable absorber rods and heavily absorbing spacer grids. KKP-II is a KWU PWR with a thermal power of 3765 MW. The project concerned is conducted by KKP in cooperation with Scandpower A/S. PRESTO-II is the PWR nodal simulator of Scandpower's code package FMS. Validation of the reactor physics methods of FMS is based on both special experimental data and comparison with actual plant data. Plant specific validation is usually performed by the utility users to qualify the method for predictive calculations. (orig.)