Thermodynamic Characterisation of Fuel Debris and Fission Products Based on Scenario Analysis of Severe Accident Progression at Fukushima-Daiichi Nuclear Power Station (TCOFF)

The TCOFF project will provide a framework for exchange of technical information on topics related to thermodynamic databases available for modelling the fuel/core degradation process, which include thermodynamic functions/models, experimental data, calculation tools, calculation methods for quasi-equilibrium systems, and prioritization of items for improvement/enlargement, with reference to the accidental scenario at Fukushima-Daiichi Nuclear Power Station (FDNPS). The project will aim at:
  • Improving the quality and/or inventory of thermodynamic databases which are used for severe accident analyses with a reference to the severe accident progression at different units of the FDNPS. Specific technical tasks related to this objective are:
    • Performing benchmark calculations by various thermodynamic databases under conditions experienced during the accidents in units 1, 2 and 3 at the FDNPS;
    • Identifying and prioritising material science concerns, in order to define specific needs of improvement and/or enlargement of current thermodynamic databases;
    • Improving and/or enlarging thermodynamic databases through experimental and analytical knowledge, provided by the Parties as in-kind contribution to the Project.
  • Conducting joint thermodynamic evaluations of the severe accident progression at in-vessel and ex-vessel phases at units 1, 2 and 3 of the FDNPS, aiming at characterizing: fuel melting; molten core relocation; fission product behaviour; fuel debris chemical and phase composition; and the thermodynamic evaluation of formation of materials which may potentially be detected at the FDNPS.


Materials Science for Severe Accident and Fukushima Daiichi Decommissioning, 10‑12 July 2019, Fukushima, Japan

Deadline for submission of abstracts: 15 May 2019

Deadline for seminar registration: 31 May 2019



Last reviewed: 18 February 2019

TCOFF working area

Management board