Scaling in nuclear thermal hydraulics: Advances, applications and future perspectives in Spain

Abstract

The demonstration of the safety, high performance and reliability of any man-made device relies heavily in experimental programs. For nuclear reactor safety demonstration, several experimental facilities are used for both testing the design and the validation of computational codes. In the field of thermal hydraulics, most experimental facilities are built at a smaller scale, thus the scaling analysis is a requirement in the licensing process of the nuclear power plant. This includes the analysis of the scaling capabilities of the computer codes, the scale and design differences with the licensed reactor and the methodologies applied for licensing.In collaboration with the Spanish regulatory Body, several Spanish university groups have contributed considerably to the development and application of scaling methodologies. This article provides an overview of the most relevant contributions presented in the last decades. The activities deal mainly with the use of system codes in scaling analysis. Specifically the works can be classified in the use of Kv scaling analyses, analysis of counterpart experiments, plant application and the scaling of uncertainties. Finally, the future challenges that will be addressed in relation to scaling are highlighted with emphasis to the contribution to the safe operation of current and future nuclear power plants.