Update of the QUENCH program

The main objective of the QUENCH program at KIT is the investigation of the hydrogen source term and materials interactions during LOCA and the early phase of severe accidents including reflood. Bundle experiments as well as separate-effects tests are conducted to provide data for the development of models and the validation of severe fuel damage code systems. The QUENCH bundle facility is a unique out-of-pile bundle facility with electrically heated fuel rod simulators and extensive instrumentation. So far, 19 experiments with various severe accident (SA) scenarios as well as a series of seven DBA LOCA experiments were conducted. The QUENCH-LOCA series was completed in 2016. One of the main results is the definition of the conditions for secondary hydriding around the burst position and its influence on the mechanical properties of the cladding rods. The last SA test QUENCH-19 was the worldwide first large-scale bundle test with ATF cladding. It was conducted with FeCrAl cladding in cooperation with ORNL, USA. First very promising results were presented by Stuckert. Separate-effects tests during 2018 were focused on the high-temperature behavior of various ATF cladding candidates. Many of these experiments were done in the framework of the EC ILTROVATORE and IAEA ACTOF programs. QUENCH bundle tests are part of the validation matrices of most SFD code systems which was also reflected during the session “Modelling and code validation”. Finally, the status of reporting and publishing as well as the numerous national and international cooperations were briefly described and acknowledged.