Publications Repository - Helmholtz-Zentrum Dresden-Rossendorf
Two-Phase Flow Studies in Complex Geometries
Neumann, M.; Bieberle, A.; Hampel, U.
In many industrial applications, two-phase flows are predominant and consist often of a liquid and a gaseous phase. Especially in nuclear power plants, those multiphase flow regimes are heavily linked to safety related issues, e.g. behavior of vapor phase in BWRs, nucleate boiling at fuel rods or steam generator tubes as well as loss of coolant accident. One approach for the safety evaluation of nuclear facilities and the prediction of hazardous conditions is the utilization of numerical models and CFD tools. Unfortunately, these methods still need a high number of empirical correlations as closure models up to now, which makes a safe prediction nearly impossible.
Additionally, most of the components in industrial applications provide complex geometries, which create pronounced three-dimensional flow phenomena, e.g. in bends, valves, junctions or heat exchangers. Especially the numerical description of those two-phase flow fields is a challenging task, which requires further experimental data for the development and validation of existing models. At the Helmholtz-Zentrum Dresden - Rossendorf (HZDR) studies in a vertical pipe have already been performed –. In these studies, a movable obstacle was used to create three-dimensional flow phenomena, which was analyzed applying wire-mesh sensor technique. Both, the motion unit of the obstacle and the wire-mesh sensor were thereby located in the flow channel, disturbing the flow field. Furthermore, the wire-mesh sensor only provided single-plane measurements.
In this contribution, continued two-phase flow studies will be described using the ultrafast electron beam X-ray scanner ROFEX to additionally measure hydrodynamic parameters of the flow field around new designed obstacles contactless.
Contribution to proceedings
47th Annular Meeting on Nuclear Technology, 10.-12.05.2016, Hamburg, Deutschland
47th Annular Meeting on Nuclear Technology, 12.05.2016, Hamburg, Deutschland