Evaluation of the dryout power density of a volumetrically heat-generating three-dimensional porous bed

A method to calculate a two-phase flow and to find the dryout region in a volumetrically heat-generating porous bed using computational fluid dynamics (CFD) is developed. It is assumed that the structure of the porous bed, cooling water and water vapor are at all saturation temperature in the boiling zone, and all the generated energy is transferred to the water by boiling where the water fraction is above a certain value. Lipinski model is used for the drag between two-phase flow and porous media. The CFD results are compared with the axis-symmetry COOLOCE tests. If a critical water fraction of 0.0025 is set as the threshold value, below which no boiling oc-curs in the porous bed, the error of the dryout power densities between the calculations and the measurement that causes the detection of the dryout in the conical bed is 4.2 - 32% depending on the system pressure.