tailieunhanh - Preliminary accident analysis of Flexblue® underwater reactor

The results of simulated transients for three typical PWR accidents are presented: a turbine trip with station blackout, a large break loss of coolant accident and a small break loss of coolant accident. The analyses show that the safety criteria are respected and that the reactor quickly reaches a safe shutdown state without operator action and external power. | Preliminary accident analysis of Flexblue underwater reactor EPJ Nuclear Sci. Technol. 1 6 2015 Nuclear Sciences G. Haratyk and V. Gourmel published by EDP Sciences 2015 amp Technologies DOI epjn e2015-50030-x Available online at http REGULAR ARTICLE Preliminary accident analysis of Flexblue underwater reactor Geoffrey Haratyk and Vincent Gourmel DCNS 143 bis avenue de Verdun 92442 Issy-les-Moulineaux France Received 11 May 2015 Received in final form 8 September 2015 Accepted 17 September 2015 Published online 05 December 2015 Abstract. Flexblue is a subsea-based transportable small modular reactor delivering 160 MWe. Immersion provides the reactor with an infinite heat sink the ocean around the metallic hull. The reference design includes a loop-type PWR with two horizontal steam generators. The safety systems are designed to operate passively safety functions are fulfilled without operator action and external electrical input. Residual heat is removed through four natural circulation loops two primary heat exchangers immersed in safety tanks cooled by seawater and two emergency condensers immersed in seawater. In case of a primary piping break a two-train safety injection system is actuated. Each train includes a core makeup tank an accumulator and a safety tank at low pressure. To assess the capability of these features to remove residual heat the reactor and its safety systems have been modelled using thermal-hydraulics code ATHLET with conservative assumptions. The results of simulated transients for three typical PWR accidents are presented a turbine trip with station blackout a large break loss of coolant accident and a small break loss of coolant accident. The analyses show that the safety criteria are respected and that the reactor quickly reaches a safe shutdown state without operator action and external power. 1 Introduction submarine cables convey both information and electricity output to the shore. A complete description of the .