The 5th test in the international CABRI (CIP) program is successful

Led by IRSN, the international CABRI (CIP) program, under the supervision of the OECD Nuclear Energy Agency, studies the behavior of nuclear fuel rods in pressurized water reactors during an accidental power excursion transient.

This test, carried out by IRSN and CEA teams on April 24, 2023, and named CIP3-3, was the fifth test in the CIP program conducted in the CABRI facility, and the third in a "water loop" configuration, representative of the thermal-hydraulic conditions of a pressurized water reactor (PWR). The fuel rod consisted of UO2 fuel and an Optimized ZIRLO cladding: a first for the CABRI facility. The simulation was carried out using a neutron pulse lasting around ten milliseconds and with a power of 13 GigaWatt.

The purpose was to study the behavior of this type of cladding, and to investigate the reaching of the boiling crisis, in an accident situation such as reactivity injection.

The rod will now be analyzed by IRSN at a dedicated station (IRIS) in the CABRI reactor hall, before being transferred at the end of the year to CEA's active fuel examination laboratory (LECA), where it will first undergo non-destructive and then destructive analysis. This, combined with the on-line measurements acquired during the pulse, will enable the most complete possible interpretation of the test.