초록 ▼

In a boiling water reactor of the type having a reactor core for heating feedwater to generate a two-phase steam/water mixture and a core shroud head overlying the reactor core and defining a core upper plenum region, a plurality of conduits disposed in the upper plenum region to provide supplementa

In a boiling water reactor of the type having a reactor core for heating feedwater to generate a two-phase steam/water mixture and a core shroud head overlying the reactor core and defining a core upper plenum region, a plurality of conduits disposed in the upper plenum region to provide supplemental water coolant. Each conduit has at least one open end located in the primary water coolant and a conduit body that extends laterally from the open end through the core shroud head and into the plenum region. Each conduit is closed with respect to the plenum region and is filled with primary water coolant during normal operation of the reactor to provide supplemental water coolant. The supplemental water coolant drains into the reactor pressure vessel when the primary coolant level falls below the open end to cool the reactor core during a loss-of-coolant accident. In one embodiment the conduit comprises a plurality of pipes, each extending laterally from the primary water collant through the core shroud head and into the core upper plenum region. The conduit may also have a grid or array configuration to enhance mixing of the two-phase mixture in the plenum region. The invention increases the total water coolant inventory present in the reactor vessel at the occurrence of a loss-of-coolant accident by displacing some of the contents of the plenum region by the supplemental coolant.

대표청구항 ▼

In a nuclear boiling water reactor of the type having a reactor core for heating water to generate a steam/water mixture, a core shroud head overlying said core and defining a core upper plenum region, and a primary water coolant inventory normally contained in said reactor to a level above said cor

In a nuclear boiling water reactor of the type having a reactor core for heating water to generate a steam/water mixture, a core shroud head overlying said core and defining a core upper plenum region, and a primary water coolant inventory normally contained in said reactor to a level above said core shroud head, a method of cooling said reactor comprising the steps of: disposing conduit means in said reactor, said conduit means having an open end located in said primary coolant and a conduit body that extends laterally from said open end through said core shroud head into said plenum region; closing said conduit body and said primary coolant with respect to said plenum region; filling said conduit means with primary coolant during normal operation of said reactor to provide supplemental water coolant; and releasing said supplemental water coolant into said reactor during a loss-of-coolant accident.