Avaliação das distorções de escala do sistema de refrigeração de cavidade de reator entre os reatores HTR-10 e HTR-PM, sob condições normais e de transientes

Abstract

The 10 MWth high-temperature test reactor (HTR-10) is a proof of concept reactor prototype for the high-temperature gas-cooled reactor pebble-bed module (HTR-PM). These reactors share several design similarities, including a reactor cavity that requires cooling owing to the high core outlet temperature. In order to ensure the integrity of the reactor cavity, a water-cooled reactor cavity cooling system (RCCS) that operates with passive heat removal processes is conceived in the project. Given the similarities between the RCCS of the reactors, this study considers the RCCS of HTR-10 as a model for RCCS of HTR-PM to evaluate the scale distortions between the RCCS. For this purpose, the RCCS is modeled and the traditional method of scale between the RCCS of the reactors is used for the steady flow regime, whereas the fractional scale analysis technique is adopted for transient flow regime. The necessary conditions for the full similarity in the steady-state flow regime are determined, as well as scale distortions for the similarity in transient flow regime are obtained. The similarity evaluation between the RCCS of both reactors based on data from two benchmark problems: pressurized and depressurized loss of forced cooling shows a similarity between the RCCS of the reactors for a given operating condition in each of the problems analyzed.