Publicou 8 edições por ano
ISSN Imprimir: 2150-3621
ISSN On-line: 2150-363X
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THERMOSIPHON−BASED PASSIVE HEAT REMOVAL SYSTEM FOR SIMULTANEOUS COOLDOWN OF REACTOR AND PRESSURIZER
RESUMO
The article discusses a proposal to introduce an autonomous passive heat removal system (PHRS) to increase the safety of nuclear power plants with the water-moderated water-cooled power reactor (WWER−1000) nuclear reactor. The residual heat is removed via heat exchangers composed from two-phase thermosiphons. The system operability can be maintained even under loss of all external power sources. The advantage of the system is its direct connection with the primary coolant circuit that provides the system compatibility with all types of light-water reactors. The system has three safety barriers to prevent activity release into the environment for any expected combinations of failures. The results of the analytical modeling carried out show that the suggested passive system provides conditions for timely injection of boric acid from hydro-accumulators (HAs) and thus sufficient subcriticality during the entire emergency process simultaneously with maintaining subcooling of the primary coolant. The results of analytical modeling of emergency cooldown of the reactor installation during a complete, long-term blackout event are presented. It is proved that the proposed PHRS provides efficient heat sink and primary depressurization. That provides conditions for actuation of the emergency core cooling system (ECCS) HAs and maintains adequate subcriticality during the transient along with maintaining subcooling conditions of the primary coolant in the reactor core.