Phenomena identification and ranking table exercise for thorium based molten salt reactor-solid fuel design

Abstract

Thorium based molten salt reactor-solid fuel (TMSR-SF) design is an innovative reactor concept that uses high-temperature tristructural-isotropic (TRISO) fuel with a low-pressure liquid salt coolant. In anticipation of getting licensed applications for TMSR-SF in the future, it is necessary to fully understand the significant features and phenomena of TMSR-SF design, as well as its transient behavior during accidents. In this paper, the safety-relevant phenomena, importance, and knowledge base were assessed for the selected events and the transient of TMSR-SF during station blackout scenario is simulated based on RELAP/SCDAPSIM Mod 4.0.

The phenomena having significant impact but with limited knowledge of their history are core coolant bypass flows, outlet plenum flow distribution, and intermediate heat exchanger (IHX) over/under cooling transients. Some thermal hydraulic parameters during the station blackout scenario are also discussed.

Key words： phenomena identification and ranking table (PIRT); thorium based molten salt reactor-solid fuel (TMSR-SF); safety analysis; RELAP/SCDAPSIM

Acknowledgment

This work was supported by Shanghai Institute of Applied Physics.

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