Pressurized-water reactor emergency core cooling system

Abstract

A pressurized-water reactor emergency core cooling system, in the event of a loss-of-coolant accident, has means for introducing at least one-quarter of the emergency cooling water supply, directly into the open space formed between and around the control rod guide tubes of the reactor's upper guide and support structure above the reactor's core and within the pressure vessel. The water introduced is under pressure and is done in such a way as to form a wide-area spray screen filling the open space with the sprayed water as completely as possible. By cooling this space via the sprayed water, the steam that would otherwise fill this space, is condensed and the reactor's internal pressure very substantially reduced, permitting the balance of the emergency cooling water, which is also introduced to the pressure vessel, to flow to the bottom of the vessel and fill it up with upwardly rising cooling water to above the upper level of the core and into the open space. Other features are included.