| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 297968 | Nuclear Engineering and Design | 2011 | 16 Pages |
In this work we investigate the present capabilities of CFD for wall boiling. The computational model used combines the Euler/Euler two-phase flow description with heat flux partitioning. Very similar modelling was previously applied to boiling water under high pressure conditions relevant to nuclear power systems. Similar conditions in terms of the relevant non-dimensional numbers have been realized in the DEBORA tests using dichlorodifluoromethane (R12) as the working fluid. This facilitated measurements of radial profiles for gas volume fraction, gas velocity, liquid temperature and bubble size.After reviewing the theoretical and experimental basis of correlations used in the model, give a careful assessment of the necessary recalibrations to describe the DEBORA tests. It is then shown that within a certain range of conditions different tests can be simulated with a single set of model parameters. As the subcooling is decreased and the amount of generated vapour increases the gas fraction profile changes from wall to core peaking. This is a major effect not captured by the present modelling. Some quantitative deviations are assessed as well and directions for further model improvement are outlined.
► In the DEBORA subcooled boiling tests using R12 are investigated. ► Radial profiles of void fraction, liquid velocity, temperature and bubble sizes at the end of the heated length were measured. ► The theoretical and experimental basis of correlations used in the wall boiling model are reviewed. ► An assessment of the necessary recalibrations to describe the DEBORA tests is given. ► With increased generated vapour the gas fraction profile changes from wall to core peaking, not captured by the present modelling.
