The present disclosure relates to a passive safety system which uses a heat exchanger together with a thermoelectric element, and a nuclear power plant comprising the same. Disclosed are a passive safety system and a nuclear power plant comprising the same, the passive safety system comprising: a heat exchanger; a thermoelectric element; and a fan unit. The heat exchanger is formed at a space inside or outside a sealed housing, and in the heat exchanger, atmosphere is introduced and heat exchange is carried out in order to lower the pressure or temperature of the atmosphere inside the housing if an accident occurs in a reactor coolant system or a secondary system disposed inside the housing. The thermoelectric element is disposed in the heat exchanger, and when a cooling fluid, for performing heat exchange with the atmosphere, performs heat exchange with the atmosphere, the thermoelectric element is configured to generate electricity due to a temperature difference between the atmosphere and the cooling fluid. The fan unit is connected to the thermoelectric element via an electricity path so as to receive electricity generated by the thermoelectric element, and is configured to increase the flow rate of the atmosphere or the cooling fluid which passes through the heat exchanger such that the heat exchange of the atmosphere and the cooling fluid can be smoothly carried out.

A nuclear reactor is provided. The reactor includes a reactor pressure vessel housing plural fuel rods containing fissile material, the reactor pressure vessel having an upper, removable, vessel head. The reactor further includes control rods, each made of a neutron-absorbing material. The control rods are inserted into the reactor through the vessel head and between the fuel rods to control the rate of the fuel rods' fission reaction. The control rods are movable over a normal range of insertion positions relative to the vessel head to control the power output of the reactor when it is critical and generating useful power, and to put the reactor in a sub-critical shutdown state. The reactor further includes control rod drive mechanisms carried by the vessel head and operable to drive the movements of the control rods. The control rod drive mechanisms are controllable to release the control rods when a vessel opening operation is performed in which the reactor is in the shutdown state and the vessel head is lifted upwards from the reactor pressure vessel such that the control rods slide therethrough to remain stationary relative to the fuel rods to maintain the shutdown state. The reactor further has monitoring unit to identify whether a control rod is accidently lifting with the vessel head.

Proposed is a passive condensation tank cooling system of a passive auxiliary feedwater system, the cooling system allowing a passive condensation tank to include an inner wall and an outer wall and a cooling means to be interposed between the inner wall and the outer wall, thereby suppressing the increase in the temperature of the heat exchange water in a condensation process in the passive condensation tank. To this end, proposed is the passive condensation tank cooling system of a passive auxiliary feedwater system, the cooling system including: a passive condensation tank having a water storage space to store heat-exchange water; and a condenser arranged to be immersed in the heat-exchange water in the passive condensation tank, wherein the passive condensation tank includes the outer and inner walls providing the water storage space and a cooling means interposed between the walls for absorbing heat of the heat-exchange water.

Nuclear reactor systems and associated devices and methods are described herein. A representative nuclear reactor system includes a heat pipe network having an evaporator region, an adiabatic region, and a condenser region. The heat pipe network can define a plurality of flow paths having an increasing cross-sectional flow area in a direction from the evaporator region toward the condenser region. The system can further include nuclear fuel thermally coupled to at least a portion of the evaporator region. The heat pipe network is positioned to transfer heat received from the fuel at the evaporator region, to the condenser region. The system can further include one or more heat exchangers thermally coupled to the evaporator region for transporting the heat out of the system for use in one or more processes, such as generating electricity.

A generator is installed on and provides electrical power from a turbine by converting the turbine's mechanical energy to electricity. The generated electrical power is used to power controls of the turbine so that the turbine can remain in use through its own energy. The turbine can be a safety-related turbine in a nuclear power plant, such that, through the generator, loss of plant power will not result in loss of use of the turbine and safety-related functions powered by the same. Appropriate circuitry and electrical connections condition the generator to work in tandem with any other power sources present, while providing electrical power with properties required to safely power the controls.

Proposed is a reactor cooling system for cooling down a reactor damaged by a disaster accident and a reactor cooling method using same using contaminated water generated at a nuclear reactor as a cooling water source for cooling the nuclear reactor after the accident, thereby maximally suppressing discharge of the contaminated water into the sea. To this end, the reactor cooling system prosed above includes a nuclear power generation facility, a seawater storage tank, a seawater inflow flow path for introducing the seawater into the seawater storage tank and a seawater discharge flow path for discharging the seawater from the seawater storage tank to the sea, connected to one end and another end of the seawater storage tank, respectively, a heat exchanger installed in a water storage space of the seawater storage tank, a contaminated water supply flow path, and a contaminated water discharge flow path.

Nuclear reactor systems and associated devices and methods are described herein. A representative nuclear reactor system includes a heat pipe network having an evaporator region, an adiabatic region, and a condenser region. The heat pipe network can define a plurality of flow paths having an increasing cross-sectional flow area in a direction from the evaporator region toward the condenser region. The system can further include nuclear fuel thermally coupled to at least a portion of the evaporator region. The heat pipe network is positioned to transfer heat received from the fuel at the evaporator region, to the condenser region. The system can further include one or more heat exchangers thermally coupled to the evaporator region for transporting the heat out of the system for use in one or more processes, such as generating electricity.

The invention relates to the field of nuclear energy, in particular, to systems that ensure the safety of nuclear power plants (NPP), and can be used in severe accidents that lead to reactor pressure vessel and its containment destruction.

The technical result of the claimed invention consists in increasing the reliability of the corium localizing and cooling system of a nuclear reactor, increase of heat removal efficiency from corium of a nuclear reactor.

The technical result is achieved through the use of the membrane and thermal shield installed in the area between the multilayer casing and the cantilever truss in the corium localizing and cooling system of a nuclear reactor.

Supports with integrated sensors for nuclear reactor steam generators, and associated systems and methods, are disclosed. A representative method for forming a nuclear-powered steam generator includes forming an instrumented support, the instrumented support including a carrier portion and a retainer portion, with at least one of the carrier portion or the retainer portion being integrally formed with a sensor via an additive manufacturing process. The method can further include coupling the sensor to a communication link, supporting a helical steam conduit on the instrumented support, and installing the helical steam conduit and the instrumented support in a nuclear reactor. The helical steam conduit is positioned along a primary flow path, which is in turn positioned to circulate a heated primary flow in thermal communication with the helical steam conduit.

The method and system for bringing a nuclear power plant to a safe state after extreme effect reduce the temperature of the coolant after extreme effect. The system includes inlet and outlet pipelines, a steam generator, a storage tank and a heat exchanger, a separation tank above the steam generator and connected by two pipelines to a storage tank, a pump, a control unit. The method involves filling the system with coolant, feeding the coolant from the steam generator through the inlet pipeline and the storage tank to the heat exchanger, and feeding the coolant through the outlet pipeline back to the steam generator, wherein the pump is turned on for feeding the coolant and subsequent operation of the system. The first air valve is used to maintain pressure in the system, ensuring the absence of boiling of the coolant.