Research reactors play an important role in higher education, scientific research, and medical radioisotope production around the world. It is thus important to ensure the safety of facility workers and the public. This work presents a new reactor transient analysis code, referred to as Razorback, which computes the coupled reactor kinetics, fuel element heat transfer, fuel element thermal expansion and thermal stress, and thermal-hydraulic response of a natural circulation research reactor. The code was developed for the evaluation of large rapid reactivity addition in research reactors, with an initial focus on the Annular Core Research Reactor (ACRR) at Sandia National Laboratories. Razorback has been validated using ACRR pulse operations, and the simulation results are shown to agree very well with measured reactor data. Razorback is also used to examine the response of a natural circulation research reactor (i.e., the ACRR) to large rapid reactivity additions. The reactor kinetic response, the thermal-hydraulic response of the fuel and coolant, and the thermomechanical response of the fuel element materials are each examined separately. Safety analysis and operational implications are discussed.
research reactor, safety analysis, reactor kinetics, thermal-hydraulics, thermal expansion, thermal stress
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Talley, Darren G.. "Investigation of the Coupled Nuclear, Thermal-Hydraulic, and Thermomechanical Response of a Natural Circulation Research Reactor Under Severe Reactivity-Initiated Accident Transients." (2019). https://digitalrepository.unm.edu/me_etds/167