Abstract: A passive cooling system for a nuclear reactor includes an energy release space in which a reactor vessel is accommodated, an energy absorbing space separated from the energy release space, and an energy transfer space above the energy absorbing space and configured to absorb and cool heat transferred from the reactor vessel and discharge the absorbed heat to an outside of the system through an outer wall thereof. The passive cooling system further includes a first cooling flow path configured to transfer the heat in the reactor vessel to the energy transfer space, a pressure balance pipe configured to transfer the pressure in the energy release space to the energy absorbing space therethrough, and a coolant spray pipe configured to transfer the cooling water in the energy absorbing space pressurized by the pressure balance pipe to the energy transfer space may be provided.

Abstract: The present disclosure relates to a radioactive material reduction facility, including a containment, a boundary section provided inside the compartment to partition an inner space of the containment into a first space for accommodating a reactor coolant system and a second space formed between the first space and the containment, and surround the reactor coolant system to prevent radioactive material discharged from the reactor coolant system or a line connected to the reactor coolant system inside the first space from being directly discharged into the second space during an accident, an in-containment refueling water storage tank (IRWST) installed between the first space and the second space and formed to accommodate refueling water, and a first discharge line formed to guide the flow of steam and radioactive material formed in the first space inside the boundary section into the in-containment refueling water storage tank.

Abstract: The present relates to the integration of the primary functional elements of graphite moderator and reactor vessel and/or primary heat exchangers and/or control rods into an integral molten salt nuclear reactor (IMSR). Once the design life of the IMSR is reached, for example, in the range of 3 to 10 years, it is disconnected, removed and replaced as a unit. The spent IMSR functions as the medium or long term storage of the radioactive graphite and/or heat exchangers and/or control rods and/or fuel salt contained in the vessel of the IMSR. The present also relates to a nuclear reactor that has a buffer salt surrounding the nuclear vessel. During normal operation of the nuclear reactor, the nuclear reactor operates at a temperature that is lower than the melting point of the buffer salt and the buffer salt acts as a thermal insulator.

Abstract: The current disclosure provides a gas-liquid falling film equilibration apparatus, systems incorporating the apparatus, and methods of their use. The apparatus comprises a chamber, an equilibration member within the chamber, liquid and gas inlet and outlets, such that a liquid introduced into the chamber from the liquid inlet contacts the upper portion of the outer surface of the equilibration member. The apparatus finds use in the measurement of dissolved gases in a variety of liquids including the measurement of carbon dioxide in water.

Abstract: In order to provide a coolant tank for preventing a containment from being recompressed and reheated during the cooling of the containment upon occurrence of a design basis accident and a severe accident and a passive containment cooling system comprising the same, the present invention comprises: a storage tank for storing a coolant; a division part which is arranged within the storage tank and divides the inside of the storage tank into a first storage tank and a second storage tank to separate the coolant; a first heat exchanger which is extended from the storage tank to the containment and cools the containment on the basis of the coolant; and a unidirectional valve which is provided on the division part and allows the coolant of the second storage tank to be introduced into the first storage tank when the water level of the first storage tank is reduced.

Abstract: The nuclear power generation system of the present invention comprises a reactor vessel. It further comprises a first crane gantry defining a fuel rod path along which nuclear fuel rods can be moved to/from the reactor vessel and a second crane gantry defining a component path along which reactor vessel components can be moved to/from the reactor vessel. The the first and second crane gantries both have a fixed radial orientation relative to the reactor vessel.

Abstract: A passive safety and cooling system for nuclear fission reactors powered by a bundle of radioactive fuel rods enclosed in a pressure vessel provides four redundant levels of dissipating and containing heat. Metal layered with carbon nanotube surrounds the pressure vessel, lines the system's floor, and studs a concrete containment dome. A retractable ceramic tile outer dome contains, absorbs and blocks any remaining heat or nuclear reactions, and optionally, releases them to the atmosphere, for the ultimate dissipation.

Abstract: A nuclear power plant containment cooling system and a spray flow control method therefor. The system comprises a cooling system liquid tank (2) for storing cooling liquid, wherein the cooling system liquid tank (2) is provided at the top of a containment (1) and the cooling liquid is used for cooling the containment (1) through the gravity of the cooling liquid itself in the situation of an accident, and the cooling liquid is partially evaporated. The nuclear power plant containment cooling system further comprises an adjustment mechanism; wherein the adjustment mechanism is provided at a liquid outlet of the cooling system liquid tank (2), and the adjustment mechanism is used for controlling the flow at the liquid outlet according to buoyancy generated by a liquid level of the collected cooling liquid which is not evaporated.

Abstract: A nuclear reactor with a liquid metal coolant includes a housing having a separating shell disposed therein. In the annular space between the housing and the separating shell are disposed at least one steam generator and at least one pump. Inside the separating shell there is an active region, above which a heat collector is disposed. The heat collector is in communication with the vertically central portion of the steam generator in order to separate a stream of liquid metal coolant into ascending and descending flows. Alternatively, the heat collector is in communication with the upper portion of the steam generator in order to create a counter-flow heat exchange regime. Below the reactor head is an upper horizontal cold collector with an unfilled level of coolant, and below the steam generator is a lower accumulating collector in communication with the upper cold collector.

Abstract: A system for attenuating seismic forces includes a reactor pressure vessel containing nuclear fuel and a containment vessel that houses the reactor pressure vessel. Both the reactor pressure vessel and the containment vessel include a bottom head. Additionally, the system includes a base support to contact a support surface on which the containment vessel is positioned in a substantially vertical orientation. An attenuation device is located between the bottom head of the reactor pressure vessel and the bottom head of the containment vessel. Seismic forces that travel from the base support to the reactor pressure vessel via the containment vessel are attenuated by the attenuation device in a direction that is substantially lateral to the vertical orientation of the containment vessel.

Abstract: A containment vessel has an inner shell covering a reactor pressure vessel and an outer shell forming an outer well which is a gas-tight space covering the horizontal outer periphery of the inner shell. The inner shell has a first cylindrical side wall surrounding the horizontal periphery of the reactor pressure vessel, a containment vessel head which covers the upper part of the reactor pressure vessel, and a first top slab connecting in a gas-tight manner the periphery of the containment vessel head and the upper end of the first cylindrical side wall. The outer shell has a second cylindrical side wall surrounding the outer periphery of the first cylindrical side wall, and also has a second to slab connecting in a gas-tight manner the vicinity of the upper end of the second cylindrical side wall and the first cylindrical side wall.

Abstract: A nuclear reactor includes a reactor core comprising fissile material disposed in a reactor pressure vessel. A radiological containment contains the nuclear reactor. A containment compartment contains the radiological containment. A heat sink includes a chimney configured to develop an upward-flowing draft in response to heated fluid flowing into a lower portion of the chimney. A fluid conduit is arranged to receive fluid from the containment compartment and to discharge into the chimney. A filter may be provided, with the fluid conduit including a first fluid conduit arranged to receive fluid from the containment compartment and to discharge into an inlet of the filter, and a second fluid conduit arranged to receive fluid from an outlet of the filter and to discharge into the chimney. As the draft is developed passively, there is no need for a blower or pump configured to move fluid through the fluid conduit.

Abstract: A passive cooling system for a reactor core of a large-scale pressurized water reactor nuclear power plant includes a shield building having an outer wall and a through air inlet arranged on an upper part of the outer wall, a water tank arranged at an upper part of the shield building, a cooling water distribution plate arranged above a top of a containment within the shield building, a spray pipe arranged at an inside of the top of the shield building and having a water inlet end and a water outlet end, wherein the water inlet end is connected to a bottom of the water tank and the water outlet end is extended to be above the cooling water distribution plate, and an air deflector arranged between the shield building and the containment and having an upper end connected to an inside of the top of the shield building.

Abstract: The submerged or underwater electricity production module according to the invention, of the type including means in the form of an elongated cylindrical box (12) in which means are integrated forming an electricity production unit including means forming a nuclear boiler (30), associated with electricity production means (37) connected to an external electricity distribution station by electrical cables, is characterized in that the nuclear boiler-forming means (30) are placed in a dry chamber (19) of the reactor compartment (18) associated with the chamber forming a safety water storage reservoir (20) of the reactor whereof at least the radial wall (53) is in a heat exchange relationship with the marine environment and in that the nuclear boiler-forming means (30) include a pressurizer (33) connected by depressurizing means (80) to the safety water storage reservoir chamber (20) of the reactor.

Abstract: Internal head vents are usable in nuclear reactors and include piping inside of the reactor pressure vessel with a vent in the reactor upper head. Piping extends downward from the upper head and passes outside of the reactor to permit the gas to escape or be forcibly vented outside of the reactor without external piping on the upper head. The piping may include upper and lowers section that removably mate where the upper head joins to the reactor pressure vessel. The removable mating may include a compressible bellows and corresponding funnel. The piping is fabricated of nuclear-reactor-safe materials, including carbon steel, stainless steel, and/or a Ni—Cr—Fe alloy. Methods install an internal head vent in a nuclear reactor by securing piping to an internal surface of an upper head of the nuclear reactor and/or securing piping to an internal surface of a reactor pressure vessel.

Abstract: A nuclear reactor includes a pressure vessel and a nuclear reactor core disposed in the pressure vessel. A subterranean containment structure contains the nuclear reactor. An ultimate heat sink (UHS) pool is disposed at grade level, and an upper portion of the subterranean containment structure defines at least a portion of the bottom of the UHS pool. In some embodiments, the upper portion of the subterranean containment structure comprises an upper dome, which may protrude above the surface of the UHS pool to define an island surrounded by the UHS pool. In some embodiments, a condenser comprising a heat exchanger including hot and cold flow paths is disposed inside the subterranean containment structure; and cooling water lines operatively connect the condenser with the UHS pool.

Abstract: A power module includes a containment vessel completely submerged in a pool of liquid, and a support structure located at or above an approximate midpoint of the containment vessel, or center of gravity of the power module. The power module is supported by the support structure in combination with a buoyancy force of the pool of liquid acting on the containment vessel.

Abstract: Heat from an ex-vessel mass of core material is removed to cooler regions of a containment envelope via liquid and/or vapor phase transport. Various aspects provide for contacting the ex-vessel core material with a material having properties including melting point, boiling point, and condensation kinetics such that condensation of the material in cooler regions of the containment envelope is at least as fast as evaporation of the material due to heat absorption from the core material and associated species.

Abstract: A head module for a large-scale container, a large-scale container having the head module, and methods for manufacturing the head module and the large-scale container. The method for manufacturing a head module comprises providing a head having an annular opening, the head being composed of a plurality of petals, providing a plurality of cylinder plates, and forming a head cylindrical ring, connecting in order the plurality of cylinder plates to the end surface of the annular opening and joining facing sides of all adjacent cylinder plates. Based on the unfitness of the petals at the annular opening of the head, gaps between adjacent cylinder plates may be adjusted, and/or the positions of the cylinder plates on the end surface of the annular opening of the head may be adjusted radially inwards or outwards.

Abstract: Efficiency of installation work of equipment such as an ECCS pump is enhanced. In an installation method of equipment, a pit can unit in which an upper side frame, a pit can, various reinforcing steels including vertical reinforcing bars reinforcing the above from a periphery, and an anchor plate supporting mechanism are integrated is manufactured in advance, and the pit can unit is placed on an MMR via a lower side frame. Further, an anchor bolt unit is disposed on the anchor plate supporting mechanism after primary concrete is deposited, a relative positional relationship of respective foundation bolts relative to the pit can is corrected by using a template, and secondary concrete is deposited under the state in which the positional relationship is corrected. After that, the ECCS pump is carried into the pit can, and an installation of the ECCS pump is completed by fixing the carried ECCS pump through the respective foundation bolts of which bottom sides are embedded.

Abstract: In a nuclear reactor building of a steel plate concrete structure that houses a pressure containment vessel formed with a plurality of penetration ports penetrating the pressure containment vessel on the periphery thereof and includes a biological shielding wall disposed outside the pressure containment vessel. The pressure containment vessel is vertically divided into a plurality of blocks so that each of the blocks has one or more pressure containment vessel penetration ports arranged on a same horizontal plane, and the reactor building including the biological shielding wall is divided into a plurality of modules by the horizontal plane.

Abstract: Efficiency of installation work of equipment such as an ECCS pump is enhanced. In an installation method of equipment, a pit can unit in which an upper side frame, a pit can, various reinforcing steels including vertical reinforcing bars reinforcing the above from a periphery, and an anchor plate supporting mechanism are integrated is manufactured in advance, and the pit can unit is placed on an MMR via a lower side frame. Further, an anchor bolt unit is disposed on the anchor plate supporting mechanism after primary concrete is deposited, a relative positional relationship of respective foundation bolts relative to the pit can is corrected by using a template, and secondary concrete is deposited under the state in which the positional relationship is corrected. After that, the ECCS pump is carried into the pit can, and an installation of the ECCS pump is completed by fixing the carried ECCS pump through the respective foundation bolts of which bottom sides are embedded.

Abstract: A system includes a containment vessel configured to prohibit a release of a coolant, and a reactor vessel mounted inside the containment vessel. An outer surface of the reactor vessel is exposed to below atmospheric pressure, wherein substantially all gases are evacuated from within the containment vessel.

Abstract: A passive cooling and depressurization system for a pressurized water nuclear plant is provided with a cooling water pool, a steam supply piping, a heat exchanger, a steam supply valve, a coolant return pipe and an outlet valve. The steam supply piping extends from the gas phase of the pressurizer. The heat exchanger exchanges heat between water stored in the cooling water pool and steam flowing through the steam supply piping. The steam supply valve is equipped on the steam supply piping. The coolant return pipe extends from the heat exchanger to a liquid phase of the reactor pressure boundary. The outlet valve is equipped on the coolant return pipe.

Abstract: A containment vessel has an inner shell covering a reactor pressure vessel and an outer shell forming an outer well which is a gas-tight space covering the horizontal outer periphery of the inner shell. The inner shell has a first cylindrical side wall surrounding the horizontal periphery of the reactor pressure vessel, a containment vessel head which covers the upper part of the reactor pressure vessel, and a first top slab connecting in a gas-tight manner the periphery of the containment vessel head and the upper end of the first cylindrical side wall. The outer shell has a second cylindrical side wall surrounding the outer periphery of the first cylindrical side wall, and also has a second to slab connecting in a gas-tight manner the vicinity of the upper end of the second cylindrical side wall and the first cylindrical side wall.

Abstract: Disclosed is an advanced process that relates to the enhanced production of energy using the integration of multiple thermal cycles (Brayton and Rankine) that employ multiple fuels, multiple working fluids, turbines and equipment. The method includes providing a nuclear reactor, reactor working fluid, heat exchangers, compressors, and multiple turbines to drive compressors that pressurize a humidified working fluid that is combusted with fuel fired in at least one gas turbine. The turbine(s) provide for electrical energy, processes or other mechanical loads.

Abstract: A drain sump of a reactor containment vessel having a containment vessel floor down below a reactor pressure vessel, and includes a heat-proof sump cover and two or more drain flow paths. The drain sump is arranged inside the containment vessel floor. The heat-proof sump cover has a thickness, and covers an upper part of the drain sump. The thickness allows a top surface of the sump cover to lie in the same surface as a top surface of the containment vessel floor. The drain flow paths pass through the sump cover in a thickness direction to flow water therethrough and solidify a molten corium therein. The molten corium is produced in the unlikely event of a severe accident.

Abstract: Disclosed is a method for removing a thermal sleeve from a cold leg of a reactor coolant system, which enables removal of an unintentionally separated thermal sleeve without implementation of a pipe cutting operation, preventing invasion of impurities into pipes and securing reliability in repetitious welding of the pipes. In particular, the method enables a remote operation and an underwater operation using wire ropes, thus being capable of minimizing a negative effect on workers due to radiation exposure.

Abstract: A nuclear engineering plant has a containment, whose interior chamber is subdivided by a wall into a systems chamber and an operating chamber which is accessible during normal operation. The containment ensures a particularly high operational reliability, in particular also in incident situations, in which hydrogen is released in the systems chamber. For this purpose, a number of overflow openings are provided in the partition wall, the respective overflow opening is closed by a closure element of a closure apparatus which opens automatically when a trigger condition associated with the respective overflow opening is reached. Closure apparatuses are provided which open both as a function of pressure and independently of pressure. The closure apparatus furthermore has a closure element containing a bursting film or a bursting diaphragm. The closure apparatus is configured such that it frees the overflow opening automatically when a predetermined environment-side trigger temperature is reached.

Abstract: A pressurized water reactor (PWR) includes: a pressure vessel divided into an upper plenum containing primary coolant, a lower plenum containing primary coolant, and a steam generator plenum interposed between the upper plenum and the lower plenum and containing secondary coolant; a nuclear reactor core comprising fissile material disposed in the lower plenum; one or more risers arranged to convey primary coolant upward from the nuclear reactor core to the upper plenum; and a plurality of tubes passing through the steam generator plenum and arranged to convey primary coolant downward from the upper plenum to the lower plenum. A steam separator is operatively connected with the steam generator plenum to separate secondary coolant in the steam phase from secondary coolant in the water phase.

Abstract: A pressurized water reactor nuclear containment radiation shield which surrounds the upper portion of a pressure vessel in an ice condenser containment. The vertical walls of the neutron shield are formed in vertical sections with the lower and upper sections operable during outages, to open to promote air flow cooling along the walls in the vicinity of the vessel head.

Abstract: An electrical penetration arrangement through the wall of a containment structure, comprising a pipe penetration having a pipe which is disposed in the wall of a containment structure, penetrating the wall, so that a first opening of the pipe is disposed outside of the containment structure, and a second opening is disposed inside the structure. Power feedthroughs are disposed in the pipe penetration having conductors sealed along their axial direction by a hermetically sealing, electrically insulating material, in which cables coming from outside can be connected to first conductor ends, and cables coming from inside the containment structure can be connected to second conductor ends. Power feedthroughs are fastened in the pipe of the pipe penetration and sealed by hermetically sealing material, so that the power feedthroughs form a hermetically sealing barrier, and the first conductor ends are disposed in the interior of the pipe.

Abstract: A nuclear installation 10 comprises a cavity 22 which is defined by at least one cavity wall 20 and which is arranged to contain nuclear fuel and a liquid for shielding radiation emitted from the fuel. A barrier 30 is arranged to be deployed within the cavity 22 to define a sub-region 34 within the cavity 20 within which fuel can be contained or transported so as to keep the fuel away from the at least one cavity wall 22 by a predetermined distance. The invention also concerns a method for refuelling a reactor vessel 18.

Abstract: A part-built nuclear reactor module 100 comprises a containment structure 12 housing therein nuclear reactor equipment 18 mounted to formwork 30. At least one concrete supply pipe 36 is provided that extends from outside of the containment structure 12 to the formwork 30. The formwork 30 can be filled with concrete through the concrete supply pipe 36 to form a concrete support structure 16 for the nuclear reactor equipment 18. A method for constructing a nuclear reactor module 10 is also provided.

Abstract: A power module assembly may include a reactor vessel containing a primary coolant and one or more inlets configured to draw a secondary coolant from the containment cooling pool in response to a loss of power and/or a loss of coolant. One or more outlets may be submerged in the containment cooling pool and may be configured to vent the secondary coolant into the containment cooling pool. A heat exchanger may be configured to remove heat from the primary coolant, wherein the heat may be removed by circulating the secondary coolant from the containment cooling pool through the heat exchanger via natural circulation.

Abstract: A nuclear engineering plant has a containment, whose interior chamber is subdivided by a wall into a systems chamber and an operating chamber which is accessible during normal operation. The containment ensures a particularly high operational reliability, in particular also in incident situations, in which hydrogen is released in the systems chamber. For this purpose, a number of overflow openings are provided in the partition wall, the respective overflow opening is closed by a closure element of a closure apparatus which opens automatically when a trigger condition associated with the respective overflow opening is reached. Closure apparatuses are provided which open both as a function of pressure and independently of pressure. The closure apparatus furthermore has a closure element containing a bursting film or a bursting diaphragm. The closure apparatus is configured such that it frees the overflow opening automatically when a predetermined environment-side trigger temperature is reached.

Abstract: The invention relates in particular to a robot system comprising a rail track and a robot, which is designed to be displaceable in a direction of movement, guided by the rail track. According to the invention, the rail track consists of a plurality of rail track segments disposed in the direction of movement, and the robot is designed to handle such rail track segments and to extend the rail track by attaching further rail track segments to a respective last rail track segment of the existing rail track. Furthermore, according to the invention, a tension member that is attached to the robot, in particular a tension cable, is provided, which runs along the rail track, wherein a winding device for receiving the tension member is provided in order to introduce a tractive force, preferably in the region of an end of the rail track.

Abstract: The present invention allows to inhibit antiplane deformation of steel plates due to the back pressure generated by water content of the concrete, and allows observation of the concrete during a service period. In a steel concrete structure including an inner steel plate exposed to a high temperature environment, an outer steel plate, studs and concrete, a steam discharging pipe and a pipe opening are provided. The steam discharging pipe includes small openings. Water content inside the concrete evaporates in a state the temperature of the concrete reaches approximately 100° C., becomes steam, is concentrated in the vicinity of the rear surface of the steel plate, and is discharged to the outside of a containment vessel from the small openings through the steam discharging pipe.

Abstract: A boiling water nuclear reactor comprises: a reactor containment vessel including a dry well and a wet well; a vent pipe connecting the dry well and the pressure suppression pool; a gravity-driven water injection pool to hold boric acid aqueous solution; an emergency core water-injection piping system for causing the boric acid aqueous solution in the gravity-driven water injection pool to fall so as to be injected into the reactor pressure vessel in case of reactor accident; a static containment vessel cooling system pool; a static containment vessel cooling system heat exchanger; a dry well connection pipe connecting an upper part of the static containment vessel cooling system heat exchanger and the dry well; and a gas vent pipe for discharging noncondensible gas in the static containment vessel cooling system heat exchanger into the inside of the pressure suppression pool.

Abstract: A system for detecting and containing a breach in a container. The container wall includes containment layers and a sensor layer sandwiched between the containment layers. The sensor layer contains a signal path that can be carried by a signal cable such as fiber optic or wire cable. The containment layers contain shards of material. When the wall of the container is compromised, the signal in the sensor layer is altered by the disturbed shards cutting the signal cable, thus allowing for the detection of a rupture, vandalism or an unauthorized access attempt, The containment layers may be composed of a gel or rubber material to slow leakage.

Abstract: An expansion gap radiation shield is formed from a flexible container housing a radiation shielding fluid, that is located within a variable gap in permanent shielding. The invention reduces radiation dose rates outside the gap when the radiation sources are located on the opposite side of the gap. The device accommodates varying gap sizes with no loss of shielding capability.

Abstract: A boiling water reactor has a reactor pressure vessel and a through piping. The reactor pressure vessel includes a main body trunk and an openable upper lid covering an upper open end of the main body trunk from above. The through piping penetrates lateral side of the main body trunk and has an opening section at a same level with or higher than the upper open end of the main body trunk in the reactor pressure vessel. The through piping may be connected to the sump arranged outside the reactor pressure vessel in the dry well. The through piping may be further connected to the suppression pool in the wet well and/or to the water level gauge in the dry well.

Abstract: A power module includes a containment vessel completely submerged in a pool of liquid,and a support structure located at or above an approximate midpoint of the containment vessel, or center of gravity of the power module. The power module is supported by the support structure in combination with a buoyancy force of the pool of liquid acting on the containment vessel.

Abstract: A reactor containment vessel of the present invention has a primary reactor containment vessel disposing a dry well for storing a reactor pressure vessel, a wet well for storing a pressure suppression pool, and an equipment room disposing below said pressure suppression pool inside thereof. Further, the primary reactor containment vessel includes an outer cylindrical wall reaching to a base mat from a top slab of the primary reactor containment vessel and facing the drywell, the pressure suppression pool and the equipment room respectively, an inner cylindrical wall facing the pressure suppression pool and the equipment room respectively, and a pressure suppression pool floor partitioning among the pressure suppression pool and the equipment room, and an outside portion of the outer cylindrical wall, an inside portion of the inner cylindrical wall, an outside portion of the ceiling and a lower portion of the pressure suppression pool floor are formed of a steel plate reinforced concrete respectively.

Abstract: A containment vessel of a boiling-water nuclear power plant and a method of operating a condenser in a nuclear power plant, include a drain pipe which connects a top region of the containment vessel to a condensing chamber disposed in the containment vessel. The drain pipe draws off noncondensible gases from the surroundings of a building condenser in the containment vessel and thus maintains reliability of performance of the building condenser. The noncondensible gases flow automatically into the condensing chamber through the drain pipe. As a result, the building condenser may have a simple and cost-effective structure.

Abstract: A containment of a nuclear power plant has a pressure chamber, a condensation chamber, and a substantially vertically running condensation tube. The upper end of the tube is connected to the pressure chamber and the lower end of the tube is immersed in a cooling liquid in the condensation chamber. The lower end of the condensation tube has an elbow and an outlet nozzle. The elbow has an elbow angle which is such that the lower end of the elbow is immersed obliquely in the cooling liquid in the condensation chamber, and the outlet nozzle has an outlet opening which is substantially shielded with respect to the base of the condensation chamber. This renders it possible to significantly reduce the pressure loads on the base and the walls of the condensation chamber in the event of an emergency.

Abstract: A nuclear reactor includes a coolant and a core. The core includes a moderator material and a plurality of fuel assemblies arranged within the moderator material, each fuel assembly including an inner region and an outer region surrounding the inner region. The inner region includes at least one first fuel structure containing at least one byproduct actinide, and the outer region includes a plurality of second fuel structures containing thermal spectrum driver fuel, the second fuel structures being less than one thermal neutron mean free path apart. Other embodiments are also provided, as is a nuclear power plant and a fuel assembly.

Abstract: A system includes a containment vessel configured to prohibit a release of a coolant, and a reactor vessel mounted inside the containment vessel. An outer surface of the reactor vessel is exposed to below atmospheric pressure, wherein substantially all gases are evacuated from within the containment vessel.

Abstract: A nuclear facility contains a flood tank, which is provided for holding a cooling liquid, a condensation chamber, and an overflow device, which leads from the flood tank to the condensation chamber and which serves to discharge excess cooling liquid. The overflow device is provided for separating gas components out from the excess cooling liquid. In certain operating states, the cooling liquid of the condensation chamber and of the flood tank is circulated in a common cooling circuit and is fed, while being largely free of gas, once more into the condensation chamber via the overflow device.

Abstract: A system for attenuating seismic forces includes a reactor pressure vessel containing nuclear fuel and a containment vessel that houses the reactor pressure vessel. Both the reactor pressure vessel and the containment vessel include a bottom head. Additionally, the system includes a base support to contact a support surface on which the containment vessel is positioned in a substantially vertical orientation. An attenuation device is located between the bottom head of the reactor pressure vessel and the bottom head of the containment vessel. Seismic forces that travel from the base support to the reactor pressure vessel via the containment vessel are attenuated by the attenuation device in a direction that is substantially lateral to the vertical orientation of the containment vessel.