TOPFLOW hot leg model experiments: Overview, examples, status of data analysis and future work

The presentation gives an overview about the experiments performed in the hot leg model built in in the pressure vessel of the TOPFLOW facility.
These experiments were conducted in a flat test-section representing a model of the hot leg of a pressurised water reactor. The region of the elbow and of the steam generator inlet chamber is equipped with glass side walls in order to allow high-speed video observations of the two-phase flow in this region. The used fluids were air and water at ambient temperature and pressures up to 0.5 MPa as well as steam and saturated water at pressures up to 5.0 MPa and temperatures up to 264°C. Four types of experiments were performed: experiments without water circulation, co-current flow experiments, steady counter-current flow experiments and counter-current flow limitation (CCFL) experiments. The test procedures, detailed test matrices and selected examples of the measurements are shown.
The current status of data analysis is presented. Data sheets were arranged in order to give an overview of the 191 runs. The water level measured during co-current flow experiments was analysed over probability distributions. Furthermore, the flooding characteristics of the hot leg model was determined and a new parameter is proposed to correlate the data. Finally, a first approach for the interface detection in high-speed camera images was presented.
In the next future, the acquired data will be compared with CFD calculations for validation purposes.