Study of the behavior of vver and pwr fuel irradiated in the hbwr reactor (halden, norway)

Abstract

The methods, techniques, and results of comparative studies of VVER and PWR fuel tested in the HBWR reactor (Norway) are presented. Experimental VVER fuel elements with uranium dioxide fuel were fabricated at the Machine Building Plant (MSZ) (in Elektrostal) using standard technology; the experimental PWR fuel elements were fabricated according to the model specifications. The results obtained made possible a comparative evaluation of the changes in the thermophysical parameters and the heat and radiation resistance of the two types of fuel as well as the kinetics of the gaseous fission products as a function of the heat load and burnup.Two experiments (IFA-503.1, IFA-503.2) studying VVER and PWR fuel fabricated by Machine Building Plant (MSZ) and by type specification, respectively, were performed in the HBWR research reactor (Halden, Norway) from 1995 to 2005. The objective of these studies was, first, to obtain, using instrumented fuel elements, representative data on the in-reactor behavior of VVER fuel during prolonged irradiation and, second, to compare under the same conditions the base in-reactor characteristics of VVER and PWR fuel, for which an extensive representative database exists. The data obtained were used for further optimization of the structural-technological parameters of VVER fuel as well as to verify the thermomechanical computer codes.The second experiment (IFA-503.2) was performed with several types of modified VVER fuel, which was fabricated taking account of the results obtained in the first experiment. The data obtained in the two experiments as well as by analyzing microstructure studies made it possible to generate recommendations on optimizing the initial microstructure of VVER fuel in order to increase its radiation resistance.This article presents data obtained from in-reactor measurements of the parameters of VVER and PWR fuel in the first comparative experiment (IFA-503.1).International Halden Project. As is well known, the Halden Project (research reactor) is one of the leading research centers for studying the behavior of fuel and materials for power reactors, first and foremost, PWR and BWR. It was created