Dryout Heat Fluxes in Debris Beds Cooled at the Bottom and Having Subcooled Liquid at the Top

Data for the dryout heat fluxes in deep beds of volumetrically heated particles are obtained when the overlying liquid is subcooled or a certain prescribed cooling condition is applied at the bottom of the particulate bed. Semitheoretical correlations proposed earlier for saturated boiling in the particulate beds with insulated bottom have been extended to correlate the data with cooling at the bottom. Visual observation of the particulate bed after dryout indicates that initial size and growth of the dryout patch significantly depends on the magnitude of the heat generation rate at the time of dryout.