555results about "Moderator/core" patented technology

A nuclear reactor including a nuclear reactor core. The nuclear reactor core includes a plurality of moderator elements, and an inverted fuel moderator block array of one or more inverted fuel moderator blocks. The one or more inverted fuel moderator blocks include a high-temperature matrix; a plurality of fuel particles embedded inside the high-temperature matrix; and at least one moderator opening for disposition of at least one of the moderator elements therein. The one or more inverted fuel moderator blocks also include at least one coolant passage formed in the high-temperature matrix to flow a coolant. The nuclear reactor can also include a reactivity control system, which can include one or more control drums, one or more control rods, or a combination thereof.

A heat pipe cooled nuclear reactor core (“reactor core”) includes an array of fuel, an array of primary heat rejection heat pipes, and an array of moderator cooling heat pipes or thermosiphons. Each moderator cooling heat pipe in the array of moderator cooling heat pipes is surrounded by metal hydride moderator materials, slowing neutrons from a fission energy range to a lower energy range in the reactor core.

A nuclear reactor is discussed herein. In some examples, the nuclear reactor may comprise an inner-core region, including liquid fuel, coolant / moderator, and a hydrogen vapor space, an out-of-core region surrounding the inner-core region, the out-of-core region including, an inner reflector adjacent to the inner-core region, the inner reflector including a first irradiation facility, and an outer reflector adjacent to the inner reflector, the outer reflector including a second irradiation facility.

Carbide-based fuel assembly includes outer structural member of ceramic matrix composite material (e.g., SiC—SiC composite), insulation layer of porous refractory ceramic material (e.g., zirconium carbide with open-cell foam structure or fibrous zirconium carbide), and interior structural member of refractory ceramic-graphite composite material (e.g., zirconium carbide-graphite or niobium carbide-graphite). Spacer structures between various layers provide a defined and controlled spacing relationship. A fuel element bundle positioned between support meshes includes a plurality of distributively arranged fuel elements or a solid, unitary fuel element with coolant channels, each having a fuel composition including high assay, low enriched uranium (HALEU). Fuel assemblies are distributively arranged in a moderator block and the upper end of the outer structural member is attached to a metallic inlet tube for hydrogen propellant and the lower end of the outer structural member is interfaced with a support plate, forming a nuclear thermal propulsion reactor.

A reactor body structure and a reactor system. The reactor body structure (100) comprises: a reactor pressure vessel (1), the reactor pressure vessel (1) comprising a bottom closure head (3), and the bottom closure head (3) having an arc-shaped inner wall (32); a reactor internal (2), the reactor internal (2) comprising a reactor core supporting lower plate (22); and a reactor core (21), the reactor core (21) being arranged on the reactor core supporting lower plate (22); wherein the reactor core supporting lower plate (22) is located on the lower side of the center of sphere of the arc-shaped inner wall (32), and the outer edge of the reactor core supporting lower plate (22) is provided with a flow guide corner (221); the reactor core supporting lower plate (22) is provided with through holes (222), the through holes (222) are stepped holes and each comprise a top hole (222a) in the upper side and a bottom hole (222b) in the lower side, and the diameter of the bottom hole (222b) is smaller than that of the top hole (222a).

A flattened temperature reactor core structure comprises a fuel assembly, and the fuel assembly comprises a base body, a fuel rod and a heat pipe. Wherein a plurality of mounting holes extending in the axial direction of the base body are formed in the axial section of the base body, the mounting holes are arranged in multiple parallel columns in the first direction, the mounting holes in the second direction forming a 60-degree included angle with the first direction are also arranged in columns, and the mounting holes arranged along the edge of the base body have the same minimum distance with the edge. Two fuel rods are arranged between every two heat pipes in the first direction and the second direction; and in the fuel rods arranged along the edge of the base body, one of two adjacent fuel rods is replaced by a vacant position. And the plurality of fuel assemblies are densely laid to form a reactor core structure. According to the reactor core structure, temperature flattening can be effectively achieved, local overheating is avoided, and therefore the efficiency and reliability of the heat pipe micro-reactor are improved. The invention also provides a heat pipe micro-stack.

The preparation method of the aluminum oxide hydrogen-resistant coating on the zirconium hydride surface disclosed by the embodiment of the invention comprises the following steps: S1, plating aluminum on the surface of a zirconium hydride matrix in a magnetron sputtering manner, and forming an aluminum film on the surface of the zirconium hydride matrix; and S2, the aluminum film formed on the surface of the zirconium hydride matrix is subjected to micro-arc oxidation to obtain aluminum oxide, and the aluminum oxide hydrogen-resistant coating is obtained. Wherein an aluminum oxide film layer formed on the surface of zirconium hydride is tightly combined with a zirconium hydride matrix, and the thickness of the film layer is 5-80 microns; the aluminum oxide film layer is composed of an inner compact layer with a non-porous structure and an outer loose layer with a closed pore structure, the thickness of the compact layer is 2-15 microns, and the compact layer has a good hydrogen permeation resistance effect; the aluminum oxide film layer on the surface of zirconium hydride can serve as an aluminum oxide hydrogen-resistant coating, the hydrogen-resistant capacity of the zirconium hydride moderator is improved, and the service life of the zirconium hydride moderator is prolonged.

A nuclear reactor having an axially stratified fuel bed. The reactor features a reactor housing having a base, a top with an exhaust port, and a shaft. An axially stratified fuel bed within a reactor housing comprising: a first zone configured to operate at a first temperature T1, the first zone comprising a plurality of first fuel pellets, each first fuel pellet comprising a first radioactive ceramic core and a first ceramic seal coating; a second zone configured to operate at a second temperature T2, wherein T2gt; t1, the second zone comprising a plurality of second fuel particles, each second fuel particle comprising a second radioactive ceramic core and a second ceramic sealing coating. A coolant fluid flow path delivers coolant fluid from the reactor base to the vent, sequentially through the first and second zones along the flow path. The stability of the first ceramic sealing coating in T1 is greater than the stability in T2, and the stability of the second ceramic sealing coating in T2 is greater than the stability of the first ceramic sealing coating in T2.

The invention provides a reactor core structure capable of controlling an assembly clearance and a manufacturing method thereof. The reactor core structure comprises a reactor core heat management element and a filling material; wherein the base body is provided with a plurality of assembly holes; the reactor core heat management element comprises a fuel rod or a heat pipe; the reactor core heat management element is assembled in the assembly hole of the base body; the filling material is filled in an assembly gap between the reactor core heat management element and the assembly hole; and the filling material is a shape memory alloy. The reactor core structure can improve the safety margin of the heat pipe reactor.

The invention discloses a reactor core for achieving 18-month circulation of a pressurized water reactor with the power exceeding 4000 MW and a loading method of the reactor core, the reactor core is composed of 177 groups of annular fuel assemblies, a 20-month refueling strategy is adopted in the first circulation, each assembly is divided into four areas to be loaded, the enrichment degrees of the assemblies in the four areas are 4.1%, 4.25%, 4.45% and 4.95% respectively, the number of the assemblies is 21, 64, 72 and 20 groups respectively, and the number of the assemblies in the four areas is 4.1%, 4.25%, 4.45% and 4.95% respectively. Placing 4.95% of the components in an outer area of the reactor core, and arranging 4.45% of the components, 4.25% of the components and 4.1% of the components in an inner area of the reactor core according to a checkerboard format; in the second cycle and the third cycle, a low-leakage refueling mode is adopted, and 2 / 3 of the reactor core, namely 108 groups of new assemblies, is loaded into the reactor core during refueling each time; and in the fourth cycle, balanced refueling is achieved, and the reactor core adopts a low-leakage refueling mode. According to the invention, after the annular fuel assembly is adopted by the pressurized water reactor consisting of 177 groups of fuel assemblies, the reactor core power is improved by 30% and reaches 4130MW compared with that when rod-shaped fuel is adopted, and the balance cycle life length still meets 18 months, so that the economical efficiency of the reactor core is obviously improved.

An installation includes: a plurality of pilings securable to a bed under a surface of a body of water; a base structure disposed atop the plurality of pilings; and a module disposable on the base structure, wherein the module is positioned and securable on the base structure after being floated on the surface of the body of water over the base structure.

The present invention relates to a method of adjusting the oxoacidity of a molten metal hydroxide salt, the method comprising the steps of: estimating a target concentration of at least one of H2O, O2−, and OH— in a molten salt of a metal hydroxide; providing an oxoacidity control component; and contacting the oxoacidity control component with the molten salt of a metal hydroxide to adjust the oxoacidity of the molten salt of a metal hydroxide. The method allows better utilisation of the available temperature range for a molten salt of a metal hydroxide by reducing the corrosive nature of the metal hydroxide.

A nuclear reactor is configured with a primary coolant loop for transferring heat away from the nuclear reactor core. In a shutdown event, the primary coolant pump may stop pumping primary coolant through the reactor core, resulting in decay heat buildup within the reactor core. An inertial energy coast down system can store kinetic energy while the nuclear reactor is operating and then release the stored kinetic energy to cause the primary coolant to continue to flow through the nuclear reactor core to remove decay heat. The inertial energy coast down system may include an impeller and a flywheel having a mass. During normal reactor operation, the flowing primary coolant spins up the impeller and flywheel, and upon a shutdown event where the primary coolant pump stops pumping, the flywheel and impeller can cause the primary coolant to continue to flow during a coast down of the flywheel and impeller.

A high-temperature gas-cooled reactor (HTGR) core is disclosed which includes a plurality of nuclear fuel kernels encapsulated by i) solid structures; and ii) porous structures, wherein the solid structures and the porous structures form a heterogeneous tileable repeating assembly including a channel for moving heat out of the HTGR core, wherein a ratio of in-channel porosity to in-channel tortuosity of the assembly is between about 0.2 to about 0.5, wherein the in-channel tortuosity is between about 1.0 and 1.6, and wherein total solid fraction of the assembly is between about 0.6 to about 0.85.

The invention provides a doped yttrium hydride neutron moderation material and a preparation method and application thereof, and belongs to the technical field of radiation shielding materials. At least one of samarium, europium and gadolinium is doped in yttrium hydride in the form of hydride, and the mass ratio of metal yttrium to metal gadolinium to metal europium to metal samarium is controlled, so that the neutron moderation effect of the neutron moderation material can be improved. According to the invention, at least one of gadolinium hydride, europium hydride and samarium hydride is mixed with yttrium hydride under the protective atmosphere, so that the mass content of each element in the doped yttrium hydride neutron moderation material can be accurately controlled. According to the invention, the mixture is sintered and molded, and the sintering parameters of sintering and molding are controlled, so that the components of the mixture are sintered in a compact state, cracks generated by thermal expansion and cold contraction can be reduced, and the doped yttrium hydride keeps high density and has fewer cracks and defects.

The invention provides a supercritical reactor, which comprises a pressure vessel cylinder, a reactor internal is arranged in the pressure vessel cylinder, and the reactor internal accommodates a peripheral fuel assembly and a middle fuel assembly; an inlet connecting pipe and an outlet connecting pipe are arranged on the pressure container barrel, a lower cavity is formed in the bottom of the pressure container barrel, and one ends of the peripheral fuel assembly and the middle fuel assembly extend to the lower cavity or are arranged above the lower cavity; coolant introduced by the inlet connecting pipe flows to the lower cavity through the peripheral fuel assembly and returns to the middle fuel assembly so as to be discharged from the outlet connecting pipe. The peripheral fuel assembly and the middle fuel assembly are arranged, a coolant entering through the inlet connecting pipe is heated downwards through the peripheral fuel assembly and then enters the middle fuel assembly to be heated, the two-flow reactor core design is adopted, fast reactor core and thermal spectrum series connection are achieved, the height of the reactor core and the density change of the coolant can be reduced, and the reactor core is more compact. The reactor core height neutron distribution is more uniform, the temperature level of a fuel cladding is reduced, and the fuel circulation characteristic is improved.

Insulated fuel assembly core with plurality of fuel monoliths, exhaust support plate, exhaust shield assembly, and insulation layer in which the plurality of fuel monoliths are located axially along a longitudinal axis and each of the plurality of fuel monoliths has a shape of an eccentric cylinder and a composition including a fissionable fuel component. Channels in the exhaust support plate are oriented so that propellant gas flow through the exhaust support plate does not impinge the exhaust shield assembly. The insulated fuel assembly core is manufactured by forming a tensioned fuel monolith stack mandrel assembly using mandrels spacers and internal tensioning components and forming an insulation layer on an outer surface of the tensioned fuel monolith stack mandrel assembly by mandrel winding. The insulated fuel assembly core can be incorporated into a fuel assembly of nuclear propulsion fission reactor structure of, for example, a nuclear thermal propulsion engine.

The invention belongs to the technical field of production of isotopes by a sodium-cooled fast reactor, and aims to solve the problems that the moderation effect is limited, the reactor core disturbance is relatively large and fast neutron energy spectrum is not beneficial to the production of the ultra-uranium isotopes during the production of the ultra-uranium isotopes. The invention provides a method for producing a super-uranium isotope by using a sodium-cooled fast reactor and a sodium-cooled fast reactor core. According to the method, moderator assemblies and super-uranium isotope production assemblies are arranged on a first circle of a radial conversion area in a flower arrangement mode, the super-uranium isotope production assemblies are arranged on a second circle of the radial conversion area, and the side, facing the center of the reactor core, of the first circle is coated with a thermal neutron absorption material; the reactor core is provided with a radial conversion area, moderator assemblies and super-uranium isotope production assemblies are arranged on a first circle of the radial conversion area, the super-uranium isotope production assemblies are arranged on a second circle of the radial conversion area, and thermal neutron absorbing materials are arranged on the side, facing the center of the reactor core, of the first circle. The super-uranium isotope is concentrated in the radial conversion region for production, the moderation effect is good, the disturbance to the reactor core is small, and the productivity is high.

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 belongs to the technical field of heat pipe reactors, and discloses a hexagonal annular heat pipe cooling reactor, which comprises a pipe wall of a heat pipe, a silk screen wick, a steam cavity structure of the heat pipe, uranium-molybdenum alloy fuel, an outer pipe wall of the heat pipe, a wick attached to the inner wall surface of the heat pipe, and uranium-molybdenum alloy. The device is formed by coupling a hexagonal annular heat pipe with a hexagonal fuel element. Firstly, in the aspect of the structure, a framework structure composed of graphite is not needed to fix the heat pipe and the fuel element, an assembly composed of the heat pipe and the fuel element can be directly adopted for expansion to form the fuel element, and gap thermal resistance brought by the framework is eliminated. In addition, in terms of heat transfer performance, the heat transfer performance of the hexagonal annular heat pipe is superior to that of a traditional cylindrical heat pipe. The same heat transfer area is adopted, and under the condition of the same heat transfer power, the temperature of the outer surface of the pipe wall of the hexagonal annular heat pipe is lower than that of a cylindrical heat pipe. Therefore, the material stress requirement in the heat pipe pile and the thermoelectric conversion form of the condensation section can be richer.

A nuclear reactor is designed to couple the load path of the control elements with the reactor core, thus reducing the opportunity for differential movement between the control elements and the reactor core. A cartridge core barrel can be fabricated in a manufacturing facility to include the reactor core, control element supports, and control element drive system. The cartridge core barrel can be mounted to a reactor vessel head, and any movement, such as through seismic forces, transmits an equal direction and magnitude to the control elements and the reactor core, thus inhibiting the opportunity for differential movement.

This invention discloses an in-core component with highly uniform core outlet flow rate and its design method, relating to the field of nuclear reactor design technology. It solves the problem of poor uniformity in coolant flow distribution at the core outlet in existing reactors, balances flow resistance at various points at the core outlet, and reduces lateral flow between different channels. The specific solution is as follows: it includes a core top plate and a support column assembly mounted above the core top plate. The core top plate is provided with several water flow holes and mounting holes. The water flow holes consist of circular and square water flow holes. The circular water flow holes are divided into first and second circular water flow holes with different functions. The area ratio of the square water flow holes to the circular water flow holes is 1.1:1 to 1.3:1.

The invention provides a reactor core structure capable of improving an assembly clearance and a manufacturing method thereof. The reactor core structure comprises a reactor core heat management element and a filling material; wherein the base body is provided with a plurality of assembly holes; the reactor core heat management element comprises a fuel rod or a heat pipe; the reactor core heat management element is assembled in the assembly hole of the base body; the filling material is filled in an assembly gap between the reactor core heat management element and the assembly hole; the filling material is a foam porous material, and the pore diameter of the foam porous material is micron-sized. The reactor core structure can improve the safety margin of the heat pipe reactor.

Carbide-based fuel assembly includes outer structural member of ceramic matrix composite material, the interior surface of which is lined in higher temperature regions with an insulation layer of porous refractory ceramic material. A continuous insulation layer extends the length of the fuel assembly or separate insulation layer sections have a thickness increasing step-wise along the length of the fuel assembly from upper (inlet) section towards bottom (outlet) section. Fuel element positioned inward of the insulation layer and between support meshes has a fuel composition including HALEU and the form of a plurality of individual elongated fuel bodies or one or more fuel monolith bodies containing coolant flow channels. Fuel assemblies are distributively arranged in a moderator block, with upper end of the outer structural member attached to an inlet for propellant and lower end of the outer structural member operatively interfaced with a nozzle forming a nuclear thermal propulsion reactor.

A nuclear reactor core includes a plurality of fuel elements and moderator blocks to form a nuclear reactor core inner portion and a nuclear reactor core outer portion. The nuclear reactor core inner portion includes an inner moderator matrix formed of a plurality of inner holes that include a plurality of inner fuel openings with one or more fuel elements disposed therein. The plurality of inner holes further include a plurality of inner coolant passages to flow a coolant. The nuclear reactor core outer portion includes an outer moderator matrix formed of a plurality of outer holes that include a plurality of outer fuel openings with one or more fuel elements disposed therein. The plurality of outer holes further include a plurality of outer coolant passages to flow the coolant. The outer coolant passage diameter exceeds the inner coolant passage diameter.

The invention discloses a treatment method for blocking open pores of nuclear graphite by adopting a silicon carbide nanostructure so as to prevent molten salt and molten metal from infiltrating graphite. Comprising the following steps: 1) mixing polycarbosilane and an organic solvent according to a mass concentration ratio of 50%-70% to form a solution, adding a catalyst to serve as a precursor solution, and completely immersing the precursor solution into graphite pores through vacuum infiltration or pressure infiltration; 2) placing the infiltrated graphite in a closed environment of 70-200 DEG C, hydrolyzing and curing the precursor solution to form a gel network, then drying in a vacuum environment of 0-300 DEG C, and forming an aerogel precursor in graphite holes; and 3) in an inert gas atmosphere or a vacuum environment, heating to 1300-1800 DEG C, and pyrolyzing the aerogel precursor to form the silicon carbide nanostructure. Compared with a traditional method, the method has the advantages of simple process, difficulty in failure, no change of the original performance of graphite and the like, and has relatively high economic value and application prospect.

The invention provides a reactor internal capable of realizing integral movement of a reactor core, and relates to the technical field of research, development and design of reactor body structures, the reactor internal comprises a hanging basket barrel, a reactor core shroud and a reactor core; the reactor core is arranged in the reactor core shroud; the reactor core shroud is arranged in the hanging basket barrel body, the reactor core shroud is movably connected with the hanging basket barrel body, the reactor core shroud slides up and down in the hanging basket barrel body, and the bottom of the hanging basket barrel body supports the reactor core shroud. According to the invention, the material changing and maintenance efficiency can be effectively improved, the downtime is shortened, the safety is enhanced, the personnel radiation exposure risk is reduced, the inspection and maintenance are convenient, and the service life of equipment is prolonged. The system adapts to advanced reactor design and conforms to the development trend of modularization and high efficiency, and the performance, safety and economical efficiency of the nuclear reactor are remarkably improved through the design of the system.

Molten salt nuclear fission reactor comprising a core through which a fuel salt flows, means (30, 31) for circulating the fuel salt, a primary heat exchanger through which a heat-transfer salt flows, a primary enclosure which is impermeable to liquid salts and contains the reactor core, and a shelter. The reactor comprises a parallelepiped matrix (10) comprising alternating layers (11) of fuel salt channels, and layers (12) of heat-transfer salt channels. The matrix forms both the reactor core, in which the fission occurs, and the primary heat exchanger of the reactor. The means for circulating the fuel salt are entirely located within the primary enclosure and are configured to extract the fuel salt from one portion of the fuel salt channels on one side of the matrix and to propel the fuel salt into the other portion of the channels on the same side of the matrix.

A nuclear power generation system capable of generating power with robust shielding against ionizing radiation is provided. This nuclear power generation system includes: a nuclear reactor that includes a core fuel, and a reactor vessel that surrounds to cover the core fuel and to shield a space having the core fuel for shielding against ionizing radiation; a thermal conductor that is disposed inside of the reactor vessel, and transfers heat of the core fuel via solid thermal conduction; a refrigerant circuit that includes a pipe with a part inserted in the reactor vessel and another part disposed outside of the reactor vessel, and through which refrigerant is passed, and that circulates the refrigerant exchanging heat with the thermal conductor; a turbine that is rotated by the refrigerant circulating through the refrigerant circuit; and a generator that is rotated integrally with the turbine.