Fuel rod performance analysis of the Kozloduy NPP WWER reactors at core reloads with the PIN-micro code

摘要

The necessity of the process of modeling the fuel behaviour at core reloading and accompanying uncertainties is substantiated. The results from numerical analysis of thermomechanical processes in fuel rods of WWER-440 (with expended core life) and WWER-1000 (with highest burnup) in the Kozloduy NPP units are reported. The quasi-two-dimensional PIN-micro code based on the G-TH-2, for steady state and slow transients, has been used. The operational margins defined are: Maximal fuel temperature <1000(sup o)C-1100(sup o)C, fission gas release <1-3%, gas pressure <80 bar, which is in the prediction capabilities of the PIN-micro code. The report is in a poster form. 14 figs., 1 tab. 15. (Atomindex citation 27:045264)