Since 18 of December 2019 uses Nucleus credentials. Visit our help pages for information on how to Register and Sign-in using Nucleus.
Apr 19 – 22, 2022
Vienna, Austria
Europe/Vienna timezone
FR22 starts in Vienna 19 - 22 April 2022 Online Stream:

Overview of the Versatile Test Reactor Safety Analysis

Apr 20, 2022, 10:40 AM
Vienna, Austria

Vienna, Austria

ORAL Track 2. Fast Reactor Safety 2.2 Safety Design and Analysis


Tyler Sumner (Argonne National Laboratory)


The Versatile Test Reactor (VTR) is a fast spectrum test reactor currently being developed in the United States under the direction of the US Department of Energy, Office of Nuclear Energy. The mission of the VTR is to enable accelerated testing of advanced reactor fuels and materials required for advanced reactor technologies. The conceptual design of the 300 MWth sodium-cooled metallic-fueled pool-type fast reactor has been led by US National Laboratories in collaboration with General Electric-Hitachi and Bechtel National Inc.
Safety analysis of the conceptual VTR design has been performed using the SAS4A/SASSYS-1 fast reactor safety analysis code with a model representing the reactor core, primary and intermediate heat transport systems, reactor vessel auxiliary cooling system (RVACS), and reactor protection system (RPS). A number of protected transients have been evaluated to demonstrate the system’s response to various initiating events. The present analysis addresses several transients that are expected to be bounding accident scenarios representing the three key ways to perturb a reactor: through changes to the mass flow rate, reactivity, or core inlet temperature. These correspond to a loss of flow (LOF) or station blackout (SBO), transient overpower (TOP), loss of heat sink (LOHS), respectively.
At the current stage of design, transient simulation results for the Versatile Test Reactor indicate that large safety margins exist for many event initiators. The RPS response following the detection of elevated plant conditions dominates the transient behaviors in these transients. Because the primary heat transport system is able to transition quickly and effectively to natural circulation and because the RVACS, which is responsible for decay heat removal, provides sufficient heat rejection, large margins for all criteria were predicted for the transients.
The work reported in this summary is the result of studies supporting a VTR conceptual design, cost, and schedule estimate for DOE-NE to make a decision on procurement. As such, it is preliminary.

Speaker's title Mr
Country/Int. organization United States of America
Speaker's email address
Affiliation/Organization Argonne National Laboratory

Primary author

Tyler Sumner (Argonne National Laboratory)


Thomas Fanning (Argonne National Laboratory) Justin Thomas (Argonne National Laboratory)

Presentation materials

Peer reviewing