The steam Direct Contact Condensation is the main phenomenon characterising the steam suppression at sub-atmospheric pressure. DCC plays an important role for the operation of the Vacuum Vessel Pressure Suppression System (VVPSS) tanks. VVPSS permits to manage the Ingress of Coolant Event (ICE cat. IV) accident condition, postulated to occur in the ITER Vacuum Vessel (VV) as a consequence of the rupture of the shielding blanket cooling piping or the rupture of the divertor cassette piping.

It is safety relevant (key) system of the fusion reactor because by condensing the steam generated during such accident event allows to damp the overpressure.

This paper deals with experimental and theoretical analyses of the steam direct condensation at sub-atmospheric pressure. The similitude analysis was elaborated to scale up the experimental results obtained in the reduced scale facility: similitude laws are used for the design of large experimental rig. Correlations have been defined starting from the water temperature and pressure variation already obtained in the small-scale rig.

Furthermore, the experimental rig and its main components accordingly designed (and under construction at the University of Pisa) to study in large and/or full scale the steam condensation in water tank at sub-atmospheric pressure as well as the testing conditions are presented and discussed.


Large-Scale Rig for the Characterization of DCC at Sub-Atmospheric Pressure

Division / Sponsors: 
Power Division & Nuclear Engineering Division (NED)

Power Conference
Paper Proceedings: https://asmedigitalcollection.asme.org/POWER/POWER2020/volume/83747

International Conference on Nuclear Engineering
Paper Proceedings: https://asmedigitalcollection.asme.org/ICONE/ICONE2020/volume/83761

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