CFD-modeling and experiments of insulation debris transport phenomena in water flow

The investigation of insulation debris generation, transport and sedimentation becomes more important with regard to reactor safety research for PWR and BWR, when considering the long-term behavior of emergency core coolant systems during all types of loss of coolant accidents (LOCA). The insulation debris released near the break during a LOCA incident consists of a mixture of disparate particle population that varies with size, shape, consistency and other properties. Some fractions of the released insulation debris can be transported into the reactor sump, where it may perturb/impinge on the emergency core cooling systems.
Open questions of generic interest are for example the particle load on strainers and corresponding pressure drop, the sedimentation of the insulation debris in a water pool, its possible re-suspension and transport in the sump water flow. A joint research project on such questions is being performed in cooperation with the University of Applied Science Zittau/Görlitz. The project deals with the experimental investigation and the development of CFD models for the description of particle transport phenomena in coolant flow. While the experiments are performed at the University Zittau, the theoretical work is concentrated at Forschungszentrum Dresden-Rossendorf.
In the current paper the basic concepts for CFD modeling are described and feasibility studies including the conceptual design of the experiments are presented.