CFD analysis of a void distribution benchmark of the NUPEC PSBT tests

The paper presents CFD calculations using CFX-12.1 on the void distribution tests of the PSBT benchmark. First, relevant aspects of the implemented wall boiling model are reviewed highlighting the uncertainties in several model parameters. It is then shown that the measured cross-sectionally averaged values can be reproduced well with a single set of calibrated model parameters for different tests cases. For the reproduction of void distribution cross-sections attention has to be focussed on the modelling of turbulence in the narrow channel. Only a turbulence model which is able to resolve the secondary flows is able to reproduce at least qualitatively the void distribution images.