Study on the defensive strategy for a immerged type research-reactor in case of station blackout accident

Layout of reactor vessel in a pool is usually used in high power and high pressure research reactor. For these reactors, the pressure vessel is immerged in a pool, both active and passive residual heat removal system was adopted by the reactor. The paper study the defensive strategy after station blackout accident, multi-condition was analyzed using Relap5 code, heat removal ability and safety of the core was studied, the suggestion was given to the strategy for the reactor after SBO accident. (authors)