Models of Pin‐wise Reconstructions in VERONA System and its Validation by MIDI‐Core Benchmark
26th Symposium of AER on VVER Reactor Physics and Reactor Safety (2016, Helsinki, Finland)
Core surveillance and monitoring continues
Abstract
MODELS OF PIN-WISE RECONSTRUCTIONS IN VERONA SYSTEM AND ITS VALIDATION BY MIDI-CORE BENCHMARKIstván Pós, Zoltán Kálya, Tamás Parkó and Sándor Patai-Szabó MVM Paks NPPABSTRACTThis year the installation of the modernized VERONA core monitoring system (version V7.0) will be finished at the NPP Paks. The VERONA applies several new models for calculations of neutron flux and thermal power inside the reactor core. One of the most important models is the pin-wise reconstruction which plays very important role both in VERONA and in off-line core calculations.The modernized pin-wise model can take into account larger area of assemblies and applies more precise spatial resolution during its calculations, than it was used in the earlier model. To describe the effect of gadolinium caused by its big neutron absorption we applied pin-wise discontinuity factors calculated by HELIOS code. The accuracy of the pin-wise reconstruction model has been increased in great extent by utilization of node-wise fluxes as boundary conditions at the border of the considered regions of assemblies as well.During the process of validation several comparisons have been done. The pin-wise power distributions calculated by new model were compared to references given by MCNP or HELIOS codes. This paper gives detailed information about the results of MIDI-core benchmark where the renewed pin-wise reconstruction model was compared to MCNP results.26th Symposium of AER on VVER Reactor Physics and Reactor Safety 30 10 – 14 October 2016, Helsinki, Finland