The DISCO-C facility serves to investigate melt dispersal from the reactor pit when the reactor pressure vessel lower head fails at low system pressure of less than 2 MPa. The fluid dynamics of the dispersion process is studied using model fluids, water or bismuth alloy instead of corium, and nitrogen or helium instead of steam.

The OECD-IAEA Paks Fuel Project aimed to support the understanding of fuel behaviour in accident conditions on the basis of analyses of the Paks-2 event. Numerical simulation of the most relevant aspects of the event and comparison of the calculation results with the available information was carried out between 2006 and 2007.

The aim of the DEFOR (Debris Bed Formation) program is clarification of the phenomena that govern formation of the debris bed in different scenarios of corium melt release into a deep water pool and quantification of the debris bed properties related to coolability.

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.

Condensation studies at LUT started with an open pool test facility (POOLEX) modeling the suppression pool of the BWR containment. During the years 2002-2006, the facility had several modifications and enhancements as well as improvements of instrumentation before it was replaced with a more versatile PPOOLEX facility in the end of 2006

VITI (‘‘VIscosity Temperature Installation’’) facility has been developed to measure viscosity, density and surface tension on corium up to 2600 C by aerodynamic levitation. But it is also used as small crucibles heating for material interactions tests. Samples of less than 100 g can be studied in VITI.

The test section of the facility consists of a scaled-down model of VVER-440 steam generator, which has a bundle of 38 tubes with inlet and outlet chambers (hot and cold chamber, respectively), and a secondary side with the steam outlet line but without droplet separators and steam dryers.

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 Mozart analytical test program, conducted from 2005 to 2007, was dedicated to the study of oxidation in air of nuclear fuel cladding.

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.

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.

The experimental programme named KAJET is being performed to investigate features of a pressurized melt jet and the interaction with substratum material. Compact melt jets, rather than a spray-type melt release, are simulated using iron and aluminium oxide instead of corium. The melt is generated by a thermite reaction.