2018 | AFC ACCOMPLISHMENTS 114 TheTransient ReactorTest (TREAT) Fuel SafetyTesting for Advanced LightWater Reactor (LWR) has continued with efforts in improving AccidentTolerant Fuels (ATFs), transient prescription testing, developing separate effects testing plans, and conducting transient prescription modeling to validateTREAT’s ability to execute fuel safety research relevant to both overpower and undercooling type transients.The transient test program has developed an inexpensive static dry capsule with a reusable primary containment to run the first fueled transient test atTREAT in September 2018 sinceTREAT was placed in standby in 1994. Project Description: The objective of theTREAT Fuel Safety Research for advanced LWR is to developAccidentTolerant Fuel for the next generation of LWR fuels with improved performance, reliability, and safety characteristics during normal operations, accident conditions and with reduced waste generation. Fuels with enhanced accident tolerance are those that can tolerate loss of active cooling in the core for a considerably longer time period than the UO2 zircaloy system while maintaining or improving the fuel performance during normal operations, operational transients, and design-basis events.The Nuclear Science andTechnology (NS&T) TransientTesting program is working on developing modular capsules that can be used to conduct transient testing experiment campaigns to test different fuel types.A dry static capsule has been developed to establish a baseline for future fueled experiments allowing a baseline comparison of data.The dry capsule is also used to conduct transient testing for separate effects testing (SET), which will allow universities to work withTREAT to perform different fueled SET experiments. NS&T is designing the static wet capsule, MinimalActivation Retrievable Capsule Holder (MARCH)- Static EnvironmentTransientTesting Apparatus (SERTTA) to primarily focus on Reactivity InsertionAccident scenarios, although it will also be used to perform a less expensive and less detail Loss of CoolantAccident (LOCA) test. NS&T is designing a natural circulation flow water capsule (Super-SERTTA) to primarily focus on LOCA testing with different fuel types, although this capsule will be able to be used for Reactivity-Initiated Accident (RIA) testing also.The transient testing program worked withTREAT operations to conduct several transient prescriptions to obtain the necessary information to properly prescribe the transients required for several series of tests. NS&T transient testing program also conducted transient prescription modeling to validateTREAT’s ability to execute fuel safety research relevant to both RIA and LOCA type transients. Fuel Safety Testing – TREAT (Advanced LWR) Principal Investigator: Dan Wachs Collaborator:Todd Pavey 2.6 Fuel SafetyTesting Fuel safety research is a vital part to determine improved performance, reliability, and safety characteristics of Accident Tolerant Fuels for Light Water Reactors.