2018 | AFC ACCOMPLISHMENTS 14 Following the disaster in Fukushima in 2011, theAccident Tolerant Fuels program (ATF) was initiated to develop improved fuel systems for light water reactors that would give reactor plant operators more time and flexibility when responding to an accident.Three fuel vendors, Framatome, General Electric, andWestinghouse responded to a call from the Department of Energy (DOE) with proposals forATF concepts. Initial scoping tests were performed in capsule experiments in theAdvancedTest Reactor (ATR;ATF-1), though it was always recognized that fuel qualification required a flowing loop with more prototypical coolant temperatures and water chemistries. Based on this need, loop testing in the central flux trap of theATR (ATF-2) was conceived and Figure 1. A picture of the boron addition system, which was developed to control boron concentrations in the loop coolant to within specified levels. executed.These steady-state tests are expected to provide important data for fuel qualification in their own right, but as importantly,ATF-2 specimens taken to specified burnups will be used for follow-on transient testing inTransient ReactorTest Facility (TREAT) and in the furnace at Oak Ridge National Laboratory (ORNL). Project Description: The ATF-2 loop test is considerably more difficult than the preceding ATF-1 capsule tests.The experiments required the development of systems to control water chemistry, holders and fuel pins that would allow for reconstitution of the test train during outages, and extensive discussions with the three fuel vendors to ensure that their programmatic needs were being met.Additional steps included Capability for Testing Light Water Reactor Fuels under Prototypical Conditions Principal Investigator: Gary Povirk Collaborators: Bryon Curnutt, Doug Crawford, Brian Durtschi, Kelly Ellis, Stephen Evans, Gary Hoggard, Paul Murray, Nate Oldham, Connor Woolum The United States now has a dedicated facility available for the steady-state testing of commercial light water reactor fuels.