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|NKS Programme Area:||NKS-R|
|Research Area:||Thermal hydraulics|
|Report Title:||Modelling of pressure loads in a pressure suppression pool|
|Authors:||Antti Timperi, Michael Chauhan, Timo Pättikangas, Jarto Niemi, |
|Abstract:||Rapid collapse of a large steam bubble is analyzed by using CFD and FEM calculations. In addition, a 1D code is written which takes into account the finite condensation rate. The 1D simulations are compared with the PPOOLEX experiment COL-01. By adjusting the condensation rate, the calculated pressure peak near the vent outlet could be made same as in the experiment. Scaling of the measured pressure loads to full-scale is studied by dimensional analyses and by review of the analysis of Sonin (1981).
The structural response of containment during chugging is studied by using an FEM of containment with simplified geometry and loading which was created based on experimental data. The results are compared to the case in which desynchronization is absent, and chugging occurs simultaneously in every vent pipe. The desynchronized loading is created by giving random initiation times for chugs out of distribution corresponding to the desynchronization time presented by Kukita and Namatame (1985).
CFD simulations of the PPOOLEX experiment MIX-03 were performed. In the experiment, clear chugging behavior was observed. In the simulation, the interphasial surface was much more stable and oscillation occurred at a higher frequency than in the experiment. The differences are likely caused by the turbulence model and too coarse numerical mesh, which causes numerical diffusion.|
|Keywords:||Condensation pool, pressure suppression pool, BWR, CFD, fluid-structure interaction, FSI, chugging, LOCA|
|Publication date:||19 Jun 2013|
|Number of downloads:||2343|