This article describes a numerical cooling analysis of pebble bed reactor (PBR) fuel pebbles, after an emergency scenario in which the nucleus disassembly is made and the pebbles are dropped into a water pool, transmitting heat by film boiling. Previously developed validation tests compared the numerical results with different experimental works available for three different geometries, which allowed the selection of numerical models and schemes with better precision and lower computational cost. The defined numerical methodology was applied for the numerical simulation of film boiling around a PBR fuel pebble. The results show that despite its decay heat, cooling occurs, with pebble surface temperature descending from an oscillatory manner, due to the instability of the vapor film. However, the temperature of this surface has a good uniformity, noting that the best and worst refrigerated area is located at the top of the pebble. The formation of multiple vapor domes at different circumferential positions is observed, which cause the hottest area of the surface to be located where biggest vapor domes were formed. The separation between vapor domes was consistent with the hydrodynamic theory, with the addition that the separation is reduced as the vapor dome evolves and grows, due to the surface curvature.