SUBJECT: Ph.D. Dissertation Defense
BY: Andrew Bopp
TIME: Thursday, March 30, 2017, 12:00 p.m.
PLACE: MARC Building, 101
TITLE: Dynamic Safety Analysis of a Subcritical Advanced Burner Reactor
COMMITTEE: Dr. Weston Stacey, Chair (NRE)
Dr. Bojan Petrovic (NRE)
Dr. Anna Erickson (NRE)
Dr. Mostafa Ghiaasiaan (ME)
Dr. Jim Grudzinski (Argonne National Laboratory)


Nuclear power provides the only technically credible option for impacting climate change in the next century. The ultimate disposal of long lived transuranics (TRU) in spent nuclear fuel is the central technical issue preventing the expansion of nuclear power. Georgia Tech's Subcritical Advanced Burner Reactor (SABR) aims to close the back end of the nuclear fuel cycle by destroying TRU. SABR is composed of 10 physically separate but neutronically coupled pool type fast reactors. In this thesis, we develop a customized dynamic safety model and use it to analyze the safety characteristics of SABR. We simulate Loss of Flow Accidents, Loss of Heat Sink Accidents, and Loss of Power Accidents. We analyze the effect of various shutdown mechanisms such as inserting control rods and shutting the fusion reactor off. We find that SABR is safe, but it is not passively safe against all accidents. The coolant boils and the fuel melts in extreme accident scenarios without corrective action taken. We find that actively shutting down the fusion neutron source within a few seconds of accident initiation prevents coolant boiling and fuel melting for all accident scenarios considered. We make recommendations on how to improve the passive safety characteristics of SABR.