EXPERIENCE WITH VVER-440 FUEL OF THE 2-ND GENERATION WITH GD (AVERAGE ENRICHMENT 4.87 %) AT SLOVAK NPP SITES
24th Symposium of AER on VVER Reactor Physics and Reactor Safety (2014, Sochi, Russia)
Reactor physics calculations, experiments and code validation
EXPERIENCE WITH VVER-440 FUEL OF THE 2-ND GENERATION WITH GD (AVERAGE ENRICHMENT 4.87%) AT SLOVAK NPP SITES
Sedláček M.1), Chrapčiak V. 1), Šimko J. 2), Greţďo O. 3)
1) VUJE, Inc., Slovakia
2) SE, Inc. – Enel, Mochovce NPP, Slovakia 3) SE, Inc. – Enel, Bohunice NPP, Slovakia
A new type of the 2-nd generation Gd fuel with average enrichment of 4.87 % has been used at Mochovce Units 1&2 since 2011 and at Bohunice Units 3&4 since 2012. Theoretical neutron-physical characteristics of reactor core are calculated by VUJE Inc. using the HELIOS and BIPR-7 programme complex. In the paper there are presented main features of the fuel and experience gained during the last 10 fuel cycles. Next, there is a comparison of theoretical and experimental neutron-physical characteristics and a discussion of the results. There are also presented some selected operational parameters such as relative power distributions (kq, kr, k0) measured by in-core monitoring systems. In the conclusion there is summarized experience with the 2-nd generation Gd fuel usage.