Direct Condensation and Entrainment Steam Experiments at the TOPFLOW-DENISE facility

In a hypothetical Small Break Loss of Coolant Accident (SB-LOCA) in a Pressurized Water Reactor (PWR), the Reactor Pressure Vessel wall (RPV) may be exposed to thermal stress, since Emergency Core Cooling Systems (ECCS) injects cold water. The loads on the primary loop and RPV walls are determined by mixing processes with the surrounding hot water and by the condensation of steam on the surface.

For the development and validation of CFD-models, experiments have to meet a high standard of reproducibility, measurement certainty and temporal and local resolution. The pressure tank technology of the TOPFLOW facility allows conducting such experiments at reasonable effort.
The Direct Condensation and Entrainment Installation for Steam Experiments (DENISE) is made for CFD-grade condensation experiments at up to 50 bars pressure. Subcooled water is injected into the DENISE-basin in three different configurations to generate stratified flow, jet and plunging jet (steam entrainment with a jet) experiments with condensation.
The experimental facility is presented along with the high degree of instrumentation. High speed camera, a particular LED illumination, infrared observation, micro thermocouples, coriolis flow meters and movable thermal lances were used.

The available set of experiments is shown together with a comparison of surface waviness and fragmentation to temperature distributions and to the resulting condensation rates.
The results will be compared to the available literature.