Pre-test analysis of protected loss of primary pump transients in CIRCE-HERO facility

Abstract

Abstract. In the frame of LEADER project (Lead-cooled European Advanced Demonstration Reactor), a new configuration of the steam generator for ALFRED (Advanced Lead Fast Reactor European Demonstrator) was proposed. The new concept is a super-heated steam generator, double wall bayonet tube type with leakage monitoring [1]. In order to support the new steam generator concept, in the framework of Horizon 2020 SESAME project (thermal hydraulics Simulations and Experiments for the Safety Assessment of MEtal cooled reactors), the ENEA CIRCE pool facility will be refurbished to host the HERO (Heavy liquid mEtal pRessurized water cOoled tubes) test section to investigate a bundle of seven full scale bayonet tubes in ALFRED-like thermal hydraulics conditions. The aim of this work is to verify thermofluid dynamic performance of HERO during the transition from nominal to natural circulation condition. The simulations have been performed with RELAP5-3D © by using the validated geometrical model of the previous CIRCE-ICE test section [2], in which the preceding heat exchanger has been replaced by the new bayonet bundle model. Several calculations have been carried out to identify thermal hydraulics performance in different steady state conditions. The previous calculations represent the starting points of transient tests aimed at investigating the operation in natural circulation. The transient tests consist of the protected loss of primary pump, obtained by reducing feed-water mass flow to simulate the activation of DHR (Decay Heat Removal) system, and of the loss of DHR function in hot conditions, where feed-water mass flow rate is absent. According to simulations, in nominal conditions, HERO bayonet bundle offers excellent thermal hydraulic behavior and, moreover, it allows the operation in natural circulation.

Steam Generator mock-up preliminary design suitable for Pb-Li technology demonstration and code assessment

“…The test section consists of a bundle of 7 DWBTs characterized by the geometrical parameter summarized in Tab. 1 and a p/d of 1.422 [9] [14] (Fig. 9).…”

Post-test simulation of a PLOFA transient test in the CIRCE-HERO facility

“…The nodalization scheme, used for pre-test simulations and for blind calculations, was developed starting from the validated thermal-hydraulic model of CIRCE-ICE, that represents the previous configuration of the facility (Narcisi et al, 2017a). The geometrical scheme was revamped for simulation of the new test section, including a relative coarse nodalization of the steam generator, consisting of a single equivalent double wall bayonet tube with a weight of seven (Narcisi et al, 2017b). The comparison between blind calculations and experimental data showed some discrepancies, attributable to an overestimation of the power removed by the SG (Lorusso et al, 2019b).…”

Pre-test analysis of accidental transients for ALFRED SGBT mock-up characterization

“…CIRCE is a multipurpose pool type facility aimed to study innovative HLM systems; it consists of the main vessel, filled with about 70 tons of lead-bismuth eutectic (LBE) and designed to host different test sections welded to the bolted heads, and two auxiliary tanks, intended to store the liquid metal during the upkeep phases and to maintain the LBE during the transfer phases (Narcisi et al, 2017a) (Turroni et al, 2001).…”