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Storage of Thermal REactor Safety Analysis data
  • SFRD

    Short fuel rod experiments were carried out in the framework of the EU 5FWP COLOSS Project. The simultaneous dissolution of UO2 pellets and ZrO2 by molten Zr was investigated with PWR and VVER samples.


    The ARISG-I was developed to estimate the aerosol deposition in the near-field of tube breach under dry conditions. It was based on ‘filter concept’, which means that aerosol flowing through a bundle of obstacles is submitted to forces that tend to clean up the gas by removing particles onto obstacle surfaces. Under SGTR conditions, the major deposition mechanisms in the break stage are turbulent deposition and inertial impaction.


    The TOSQAN experimental vessel is a large stainless steel cylindrical enclosure (volume 7m3, height 4m, internal diameter 1.5m) with double walls. A coolant circulates in between the walls to regulate the wall temperature from 60 °C to 160 °C. Non radioactive aerosols, steam and non explosive gases can be injected at different controlled flow rates via diverse injection pipes located at different locations of the enclosure. Different instrumentation is used, namely PIV (particle image velocimetry), LDV (laser doppler velocimetry), rainbow refractometry, out of focus imaging and SRD (spontaneous Raman diffusion) spectrometry.


    The VERCORS programme, which involves tests with short fuel-rod samples, has proved to be a rich source of information regarding FP release and tranport.


    The Mozart analytical test program, conducted from 2005 to 2007, was dedicated to the study of oxidation in air of nuclear fuel cladding. This study was part of the International Source Term Program initiated by the IRSN, whose aim is to reduce uncertainties concerning the evaluation of radioactive product emissions into the environment in the event of a core meltdown accident in a pressurized water reactor or a spent fuel storage pool accident.


    The QUEOS facility serves to study premixing phenomena with solid spheres, i.e. without the danger of a steam explosion and the complication of melt fragmentation. Emphasis was put on high sphere temperatures (up to 2600 K) and the use of large numbers of comparatively small spheres so that intensive multiphase interactions with strong coupling of the phases (collective motion of the spheres) are observed. In order to simulate melt jets as closely as possible, the spheres are released as a cylindrical jet into a three-dimensional test vessel.


    The MISTRA facility is a steel cylindrical vessel with a top flat cap and a curved bottom. The internal volume is 99.5m3, the internal diameter - 4.25m, the height - 7.4m. The vessel is thermally insulated, but the wall temperature is not controlled. Three cylindrical condensers are inserted inside the vessel, close to the wall and one above the other (so that they span over most of the vessel height). The facility is designed in such a way that almost all steam condensation is supposed to occur on the interior side of the condensers. The facility was additionally equipped with sprays located below the vessel ceiling. The instrumentation includes devices for measuring pressure, temperature, gas concentration and velocity (laser Doppler anemometry).

  • Epicur

    The Epicur programme (physicochemical studies on confined iodine under irradiation) aims at providing experimental data to validate the chemical models for iodine in the reactor containment under accident conditions. These models are integrated into the Iode model of the Astec computer code, jointly developed by IRSN and GRS. They are used to predict the behaviour of different types of possible accidents and related releases of radioactive products.


    The DISCO-H test facility was set up to perform scaled experiments that simulate melt ejection scenarios under low system pressure in Severe Accidents in Pressurized Water Reactors (PWR). These experiments are designed to investigate the fluid-dynamic, thermal and chemical processes during melt ejection out of a breach in the lower head of a PWR pressure vessel at pressures below 2 MPa with an iron-alumina melt and steam.

  • PCCS

    Passive Containment Cooling System (PCCS) removes residual heat from upper drywell of the containment to the liquid pool surrounding the PCCS heat exchanger. It also has an important role in mitigating the offsite dose by retention of a fission product release in the containment. The operation of the PCCS is based on density differences between the containment and water pool


    The PHEBUS FP (Fission Products) international research programme was conducted between 1988 and 2010. Its purpose was to improve the understanding of the phenomena occurring during a core meltdown accident in a light water reactor and to validate the computational software used to represent these phenomena in reactor safety evaluations. The report of the last test was published in December 2010 and was the topic of a closing seminar organised in June 2012.

  • ECO

    In case of a steam explosion, e.g. as a consequence of a severe reactor accident, part of the thermal energy of the melt is transferred into mechanical energy. At Forschungszentrum Karlsruhe, the ECO experiments are being directed to measure the conversion factor under well-defined conditions. The programme was launched in 2000. Alumina from a thermite reaction is used as a simulating material instead of corium. Dimensions of the test facility as well as major test conditions, e.g. temperature and release mode of the melt, water inventory and test procedure, are based on the former PREMIX experiments (from 1994 to 1999).

Storage of Thermal REactor Safety Analysis Data

STRESA was developed by JRC-Ispra in the year 2000 with the main objective to disseminate documents and experimental data from large in-house JRC scientific projects, and has been extensively used in order to provide a secure repository of experimental data.

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At present time the JRC is engaged in the management of this new version of the STRESA tool to secure the European Union storage for severe accident experimental data and calculations.

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