Arrangement for the core decay heat removal of a pressurized water nuclear reactor.

摘要

Device for removing the residual power from the core of a pressurised-water nuclear reactor, comprising a primary water circulation along a hairpin path in the reactor vessel (2), comprising for this purpose two concentric shells (2, 6) defining an outer annular compartment (3) in which the cold primary water describes a downward path, and a central cylindrical compartment (10) containing the core (4) itself, in which the primary water flows from the bottom upwards while being heated through the core, characterised in that it comprises: - a third shell (7) defining an additional annular space (8) between the above two compartments (3, 10), this annular space (8) being placed in communication, in its lower part, via a small orifice (12) emerging into the outer annular compartment (3), with the cold water of the primary circuit and, in its upper part, via a second orifice (11) emerging into the central compartment (10), with the hot water of the primary circuit; - an auxiliary heat exchanger (9) situated in this additional annular space (8), this auxiliary exchanger (9) being fed autonomously with a second heat transfer fluid independent of the primary water coolant of the reactor core.