IAEA ATF-TS Benchmark for simulation of bundle tests

Since 2021, IAEA has been organizing a Coordinated Research Project (CRP) on Testing and Simulations of Accident Tolerant and Advanced Technology Fuels (ATF-TS). A work sub-task WT2.2 is dedicated to benchmark the integral computer codes used for simulation of bundle tests with ATF cladding materials. The following three bundle tests, carried out under severe accident conditions, were selected for the simulation: CODEX-ATF (HUN-REN EK/Hungary) and DEGREE (CRIEPI/Japan) both with chromium coated Zr-alloy cladding tubes, and QUENCH-19 (KIT/Germany) with FeCrAl cladding tubes. Seven organizations using six different codes took part in the post-test simulation of the QUENCH-19 test. The preparation of the CODEX-ATF test was based on calculations carried out with three codes in three organizations; four organizations are participating in the post-test simulation currently underway. Four institutes with four different integral codes were participated in the pre- and post-test modelling of the DEGREE-B3 bundle test.
This paper presents briefly the chosen bundle tests, the participants and codes used, and a comparison of the simulation results.