Investigation of ex-vessel core catcher for SBO accident in VVER-1000/V528 containment using MELCOR code

作     者：Farhad Salari Ataollah Rabiee Farshad Faghihi Farhad Salari;Ataollah Rabiee;Farshad Faghihi

作者机构：Department of Nuclear EngineeringSchool of Mechanical EngineeringShiraz UniversityShiraz 71936-16548Iran Radiation Research CenterShiraz UniversityShirazIran Ionizing and Non-Ionizing Research CenterShiraz University of Medical ScienceShirazIran 

出 版 物：《Nuclear Science and Techniques》 (核技术（英文）)

年 卷 期：2021年第32卷第4期

页      面：92-111页

核心收录：

学科分类：082704[工学-辐射防护及环境保护] 08[工学] 0827[工学-核科学与技术] 

主　　题：Core catcher VVER-1000/V528 Containment SBO accident MELCOR Environmental radionuclide release Corium cooling 

摘      要：To mitigate consequences of core melting,an ex-vessel core catcher is investigated in this *** should be obeyed to cool down the corium caused by core *** corium destroys the reactor containment and causes radioactive materials to be released into the environment if it does not cool down *** is important to build a core catcher system for the reception,localization,and cool down of the molten corium during a severe accident resulting from core *** this study,the role of a core catcher in the VVER-1000/v528 reactor containment during a station black out(SBO)accident is evaluated using the MELCOR1.8.6 *** addition,parametric analyses of the SBO for(i)SBO accidents with emergency core cooling system(ECCS)operation,and(ii)without ECCS operation are ***,thermal–hydraulic analyses in dry and wet cavities with/without water are *** investigations include the reduction of gases resulting from molten–corium–concrete interactions(H_(2),CO,CO_(2)).Core melting,gas production,and the pressure/temperature in the reactor containment are ***,a full investigation pertaining to gas release(H_(2),CO,CO_(2))and the pressure/temperature of the core catcher is *** on MELCOR simulations,a core cavity and a perimeter water channel are the best options for corium cooling and a lower radionuclide *** simulation is also theoretically investigated and discussed *** simulation results show that the core catcher system in addition to an internal sacrificial material reduces the containment pressure from 689 to 580 kPa and the corresponding temperature from 394 to 380 ***,it is observed that the amount of gases produced,particularly hydrogen,decreased from 1698 to 1235 ***,the presence of supporting systems,including an ECCS with a core catcher,prolonged the core melting time from 16,430 to 28,630 s(in an SBO accident)and significantly decreased the gases produced.