Critical heat flux for downward-facing pool boiling on CANDU calandria vessel

Under a severe accident condition in CANDU reactors, damage to the reactor is expected such that a significant amount of core material can melt and relocate downward to the bottom of the vessel. It is essential that the vessel remains intact and mechanically strong to accommodate the core melt. However, a thermal creep failure is postulated to occur if sustained critical heat flux is instigated in the surrounding shield tank water. A …