308results about "Fuel element assemblies" patented technology

Insulated fuel assembly core with axially arranged fuel monoliths including channels and having a composition including a fissionable fuel component, exhaust support plate, exhaust shield assembly, and insulation layer. Fuel monoliths have an eccentric cylinder shape or a right circular cylinder shape with side surface keyway. The eccentric shape and / or a keyway (with associated alignment rod) provide alignment. Channels in the exhaust support plate are oriented so propellant gas flowing from the fuel monoliths through the exhaust support plate does not impinge the exhaust shield assembly. Insulated fuel assembly cores are manufactured by forming a tensioned fuel monolith stack mandrel assembly using mandrel spacers and internal tensioning components and mandrel winding an insulation layer on an outer surface of the tensioned fuel monolith stack mandrel assembly. Insulated fuel assembly cores can be incorporated into fuel assemblies of nuclear propulsion fission reactor structures, for example, a nuclear thermal propulsion engine.

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.

The invention provides a nuclear fuel grillwork clamping device and a vibration acceleration control method, and relates to the technical field of nuclear fuel grillwork clamping devices.The nuclear fuel grillwork clamping device comprises the steps that a plurality of clamping pieces are slidably installed in a nuclear reaction box body in the first direction and connected with the multiple clamping pieces at the same time through a transmission mechanism, and the clamping pieces are connected with the nuclear reaction box body through the structural characteristics of the transmission mechanism; and the plurality of clamping pieces are enabled to vibrate in two opposite directions of the first direction. Based on the structural design, the mode that the clamping pieces are installed in the nuclear reaction box body is changed into sliding connection from fixed connection, and the multiple clamping pieces are connected at the same time through the transmission mechanism. In the nuclear reaction process, the transmission effect of the transmission mechanism can be utilized to enable the plurality of nuclear fuel grillages to vibrate along opposite directions; therefore, the vibration amplitude of the nuclear fuel grillwork is reduced, and finally the purpose of reducing the failure rate of the nuclear fuel grillwork is achieved.

The present invention relates to a nuclear fuel assembly suitable for a small modular reactor (SMR), the nuclear fuel assembly comprising: a spacer grid (110) having 17x17 grid cells; a plurality of fuel rods (120) arranged in the grid cells of the spacer grid (110); guide tubes (130) arranged and fixed in the grid cells of the spacer grid (110); and an upper end fitting (140) and a lower end fitting (150) fixed to the upper end and the lower end of the guide tubes (130), respectively, wherein the guide tubes (130) are characterized in that eight guide tubes are arranged in the main axis directions (Ixx)(Iyy) with respect to the central cell of the spacer grid (110), four guide tubes are arranged in the diagonal direction (Ixy), and sixteen guide tubes are arranged in the non-diagonal directions (Ixxy)(Ixyy).

The invention belongs to the technical field of nuclear fuel assembly design, and particularly relates to a high-safety fuel assembly capable of measuring temperature and conducting strong flow guiding. Comprising a temperature-measurable instrument tube, a strong flow-guiding grillwork, a fuel rod, a guiding tube, a foreign-matter-catching-preventing lower tube seat, a low-pressure-drop upper tube seat and a connecting structure thereof. Through the arrangement of the structure and the connection of all the components, the high thermotechnical safety margin of the fuel assembly is realized. By arranging the temperature-measurable instrument tube, a temperature sensor can be placed in the temperature-measurable instrument tube, the temperature of a coolant entering the temperature-measurable instrument tube from the radially uniformly distributed drain holes can be continuously measured on line in real time, the actual thermotechnical safety margin of the fuel assembly can be known, operation can be fed back, operation strategy optimization can be guided, and transient state and low accident incidence of the fuel assembly are realized; by measuring and feeding back the coolant temperature of the hot spot part of the fuel assembly, the fuel assembly and the power plant can operate at safe and as high as possible parameters for a long time based on the mastered safety margin, and the economical efficiency of the nuclear power plant is improved.

The invention relates to the technical field of nuclear reactor design, in particular to an air-cooled nuclear reactor system for series thermal ionization magnetohydrodynamic power generation. Comprising a reactor core which comprises a fuel grid which is formed by a plurality of grid unit plates which are crossed transversely and longitudinally; each grid unit plate is made of sheet-shaped fuel; the thermal ionization magnetohydrodynamic power generation element is arranged outside the reactor core and is used for providing a magnetic field for the fuel grid; the cooling system is used for providing rare gas for the reactor core and is configured to enable the rare gas to exchange heat with the fuel grid and to be converted into conductive fluid in a generated magnetic field, and the conductive fluid flows in the generated magnetic field to generate induced electromotive force so as to realize thermoelectric conversion. While high thermoelectric conversion efficiency is ensured, the engineering feasibility of an air-cooled nuclear reactor system is improved, and the problems that gaseous nuclear fuel is prone to corrode structural materials, prone to leakage and large in aftertreatment difficulty are solved.

Systems, structures, devices, and fabrication processes for ceramic matrix composites suitable for use in a nuclear reactor environment and other applications requiring materials that can withstand high temperatures and / or highly corrosive environments are disclosed. In one aspect, a ceramic composite structure is provided. The structure comprises a chamber including an external shell and a hollow space inside the external shell. The external shell includes an inner composite layer including a first composite structure, a middle composite layer placed outside of the inner composite layer, the middle composite layer including a second composite structure that is different from the first composite structure, and an outer monolithic layer that has a spatially uniform material property and placed outside of the middle composite layer.

The invention discloses an upper pipe seat of a fuel assembly. The upper pipe seat comprises an upper seat body and a plurality of adjusting assemblies, the upper seat body is provided with a sliding rail part and a guide sliding groove, and the sliding rail part is obliquely arranged relative to the horizontal plane. Each adjusting assembly comprises a fixing block, an adjusting piece, a sliding block and an elastic structure. The fixed block is fixedly installed on the upper seat body, the sliding block is movably connected with the sliding rail part and corresponds to the fixed block, the adjusting piece is in transmission connection with the fixed block and used for pushing the sliding block to move along the sliding rail part, the first end of the elastic structure is fixedly connected with the sliding block, and the second end of the elastic structure is movably connected into the guide sliding groove. According to the fuel assembly upper tube base, the adjusting assembly is installed on the upper base body to compensate for the insufficient pressing force, meanwhile, the initial compression amount of a compression spring of a full-reactor-core fuel assembly is reduced, and the fuel assembly bending risk caused by the too large pressing force of the fuel assembly can be effectively reduced. Meanwhile, due to the arrangement of the adjusting assembly, the elastic structure can be located at different heights so as to meet different functional requirements.

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.

The invention provides a nuclear fuel rod pile internal damage characteristic recovery experiment device, and relates to the technical field of nuclear fuel grillwork experiment devices, and the nuclear fuel rod pile internal damage characteristic recovery experiment device comprises the following steps: fixing a grillwork in an experiment box by using a first clamping assembly; the second clamping assembly is installed on the vibration assembly, and the vibration assembly is installed in the experiment box. And clamping the fuel rod by using a second clamping assembly. The vibration assembly drives the second clamping assembly and the fuel rod to vibrate, so that the fuel rod and the elastic reed rub with each other, and an abrasion experiment of the fuel rod and the grillwork elastic reed can be completed; and the fuel rod can also apply an acting force to the elastic reed, so that the fatigue test of the elastic reed can be completed. The experimental device can drive the fuel rods to repeatedly rub with the elastic reeds in the through holes of the grillwork or enable the fuel rods to repeatedly extrude the elastic reeds, so that the technical problem that an existing experimental device is difficult to meet two experiments at the same time is solved.

The invention discloses a small liquid-solid dual-fuel molten salt reactor core loaded with a cross spiral fuel, and relates to the technical field of nuclear reactor engineering. The reactor core of the small liquid-solid dual-fuel fused salt reactor loaded with the cross spiral fuel comprises two parts, namely an active area and a control drum, the control drum comprises a reflecting layer and a control drum absorbing material, the reflecting layer is made of beryllium oxide, and the control drum absorbing material is boron carbide with the boron 10 enrichment degree of 100%; the active area is composed of a fuel element and a fluoride salt coolant, and the whole active area is packaged in a shell made of Zr-4; the fuel element is in a cross spiral shape and is arranged in a regular hexagon shape, the fuel element is composed of an axial reflecting layer, fuel, a He cavity and an Re absorber, and the fuel is UC solid fuel with the U-235 enrichment degree being 45.684 wt.%; the material of the fluoride salt coolant is 7LiF-KF-UF4 (49.55 to 49.55 to 0.9 mol%), wherein the enrichment degree of U-235 in the UF4 is 30 percent by weight. According to the invention, the reactor core power density is further improved and the fuel peak temperature is effectively reduced while the reactor core heat is ensured to be discharged in time.

The invention relates to a nuclear reactor (1) having solid fuel assemblies (2) that are sealed and cooled individually in nominal operation by heat pipes (23). The invention substantially consists of a nuclear reactor (1) that operates in the fast neutron spectrum and is cooled by an array of one or more heat pipes (23). At least part of the evaporator (231) of one or more heat pipe(s) (23) is held and partially housed with one or more rods (22) of solid fuel pellets which are enclosed in a sheath in a sealed assembly which is partially filled with a liquid metal bath (21), which can be defined as a thermal seal between the rod sheaths and the heat pipes (23). The core (11) of the reactor (1) consists of an array of these sealed assemblies (2) (fuel rod(s) and heat pipe(s) immersed in a liquid metal bath) arranged within a tank (10) surrounded by a neutron reflector (12).

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 discloses a zirconium alloy cast ingot, a high-quality Zr-Sn-Nb alloy strip for nuclear power and a preparation method and application of the high-quality Zr-Sn-Nb alloy strip. According to the method, a direct hot rolling coiling process of the zirconium alloy large plate blank is adopted, the technical parameters of hot continuous rolling of the large plate blank, namely the plate blank thickness, the hot rolling temperature, the rolling speed and the pass deformation, are mainly controlled, and the key performance such as zirconium alloy corrosion is guaranteed; according to the process, the deformation amount is increased, the basal texture is weakened, the transverse texture is improved, and the structure performance of the finished strip is improved.

The invention discloses an assembly method of a heat pipe type reactor and the heat pipe type reactor, and belongs to the field of nuclear power. The assembly method of the heat pipe type reactor comprises the following steps: closing one end of each mounting hole of the grid base body, vertically arranging the grid base body to enable the closed end to be located at the bottom, injecting filling slurry containing heat-conducting powder and a dispersing agent into the mounting holes, then inserting pipe fittings into the mounting holes until the filling slurry overflows, and finally assembling the grid base body into the mounting holes. The gap between the pipe fitting and the mounting hole is uniformly filled with the filling slurry in a forced flowing mode; and heating to cure and shape the filling slurry. The method can effectively eliminate the assembly gap between the grid substrate and the pipe fitting of the heat pipe type reactor, and improves the heat transfer efficiency and the safety margin of the 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.

The invention discloses a fuel assembly grillwork and a nuclear fuel assembly. A lower guide sliding rail structure in the fuel assembly grillwork is arranged at the bottom end of a grillwork body, and an upper guide wing is arranged at the top end of the grillwork body; the lower guide slide rail structure comprises a plurality of transverse strips and a plurality of longitudinal strips which are respectively arranged in parallel, and divides the bottom of the grillwork body into a plurality of grids; the two ends of each transverse strip in the multiple transverse strips and the two ends of each longitudinal strip in the multiple longitudinal strips are obliquely provided with guide sliding rails. According to the grillwork structure, the hooking risk can be reduced, and the lower guide sliding rail structure cannot be inserted into the upper guide wing in the lower grillwork when the grillwork structure is in contact with the lower grillwork, so that the situation that an outer strip of the grillwork falls off due to hooking of adjacent fuel assemblies is avoided; the pressure drop of the whole grillwork is reduced, and fluid exchange between the interior of the grillwork and the edge of the grillwork is strengthened; meanwhile, the grillwork has low pressure drop, and a lower guide wing structure is omitted.

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.

The present invention relates to the field of nuclear fuel technology, and specifically discloses a high-reliability fuel assembly with coordinated flow control, including a lower tube seat, a skeleton, an upper tube seat, and fuel rods, guide tubes, and instrument tubes inserted into the skeleton, which are sequentially arranged along the flow direction of the coolant; the lower tube seat is a low-outlet lateral flow lower tube seat; on the lower tube seat connecting plate, there are a number of space-through slender flow channels with a width less than the fuel rod spacing and axial bending; the outlets of the surrounding flow channel areas of the space-through slender flow channels located on the outer periphery of the lower tube seat connecting plate are higher than the outlets of the middle flow channel areas located in the middle of the lower tube seat connecting plate, so as to reduce the lateral flow of the outlets between assemblies. The present invention carries out a coordinated and innovative design of the fuel assembly as a whole, and ensures a high thermal safety margin of the fuel assembly.

The nuclear fuel assembly comprises grids distributed along the length of nuclear fuel rods (4), the grids including spacer grids (14), at least one reinforcing grid (16), a lower end grid (18) and an upper end grid (20). The spacer grids (14) define, between them and together with the lower end grid (18) and the upper end grid (20), a plurality of intervals (15). The grids further include one or more intermediate mixing grids (22) and, optionally, an anti-debris grid (24) in which the lower ends of the nuclear fuel rods (24) engage.

The utility model belongs to the technical field of fuel elements for nuclear reactors, and discloses a guide pipe, a guide pipe assembly and a pressurized water reactor fuel assembly. The guide pipe comprises a pipe body and two water hole assemblies, the pipe body is oppositely provided with a first end and a second end in the axial direction of the pipe body, the two water hole assemblies are arranged at the position, close to the first end, of the pipe body and the position, close to the second end, of the pipe body respectively, and the two water hole assemblies are symmetrically arranged in the radial direction of the center of the pipe body; the water hole assemblies are arranged at the two ends of the pipe body in the axial direction of the pipe body and used for discharging water flow during rod falling, that is, the pipe body has a mistake-proof function, so that when the guide pipe is installed, whether the guide pipe and the end plug are installed reversely or not does not need to be considered, the problems that the guide pipe assembly, a framework and a pressurized water reactor fuel assembly are scrapped and the like are avoided, and the production efficiency is improved. The installation reliability of the guide pipe is improved, and the safety of the pressurized water reactor fuel assembly loaded with the guide pipe is further improved.

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. Thus, any movement, such as through seismic forces, transmits an equal direction and magnitude to the control elements and the reactor core. This arrangement reduces the opportunity for differential movement between the control elements and the reactor core.

A fuel assembly comprises a fuel assembly intermediate structure 250 circumferentially enclosing an interior volume, a fuel element bundle 190 located within the interior volume with the fuel assembly intermediate structure radially outward of the fuel element bundle, an insulation layer 160 radially outward of the fuel assembly intermediate structure 250, a void space 255 between an inner surface of the insulation layer 160 and an outer surface of the fuel assembly intermediate structure 250, a fuel assembly outer structure 110 radially outward of the insulation layer 160, and a second void space 265 between an outer surface of the insulation layer 160 and an inner surface of the fuel assembly outer structure 110. The fuel element bundle includes a plurality of fuel elements 105 and a coolant flow volume 115, through which a coolant in a form of a propellant gas flows during operation of a reactor containing the fuel assembly, so that the coolant contacts exterior surfaces of the fuel elements 105.

The embodiment of the invention relates to assembling equipment of a reactor fuel element, in particular to sodium bonding equipment of a metal fuel rod. The sodium binding equipment comprises a fuel rod supporting frame, a heating device and an impact device. A plurality of containing grooves are formed in the fuel rod supporting frame, and each containing groove is used for containing a metal fuel rod. A heating cavity is formed in the heating device, the fuel rod supporting frame is partially contained in the heating cavity, and the heating device is used for heating the metal fuel rod, so that solid sodium in the metal fuel rod is melted into liquid sodium. The impact device is arranged to impact the fuel rod supporting frame upwards, and when the impact device impacts the fuel rod supporting frame, an axial impact load and a tangential impact load are generated, so that the metal fuel rod freely falls after rising, and meanwhile, the metal fuel rod rotates and deviates in the tangential direction to eliminate the defects in the liquid sodium.

The application discloses a fuel assembly upper tube support, which comprises an upper seat body and a plurality of adjusting assemblies. The upper seat body is provided with a sliding rail part and a guide sliding groove, and the sliding rail part is arranged obliquely relative to a horizontal plane. Each adjusting assembly comprises a fixing block, an adjusting piece, a sliding block and an elastic structure. The fixing block is fixedly installed on the upper seat body, the sliding block is movably connected with the sliding rail part and is correspondingly arranged with the fixing block, the adjusting piece is in transmission connection with the fixing block and is used for pushing the sliding block to move along the sliding rail part, and the first end of the elastic structure is fixedly connected with the sliding block, and the second end of the elastic structure is movably connected in the guide sliding groove. The fuel assembly upper tube support can compensate for the shortage of the pressing force by installing the adjusting assembly on the upper seat body, simultaneously reduce the initial compression amount of the fuel assembly pressing spring of the whole core, and effectively reduce the bending risk of the fuel assembly caused by the excessive fuel assembly pressing force. Meanwhile, the adjusting assembly can also make the elastic structure be at different heights to meet different functional requirements.

Anti-debris filter for lower nozzle of nuclear fuel assembly with variable thickness The anti-debris filter is formed of a grid (32) having a first face (32A) and a second face (32B) opposite each other, the grid (36) having passages (36) extending between an inlet (36A) located on the first face (32A) and an outlet (36B) located on the second face (32B) for the flow of a coolant through the grid (32), the grid (32) having a first zone (Z1) and at least one second zone (Z2) in which the grid (32) has a thickness greater than that of the grid (32) in the first zone (Z1), passages (36) being present in the first zone (Z1) and in each second zone (Z2). Figure for abstract: Figure 7

The present invention belongs to the technical field of reactor fuel assemblies, and specifically relates to a guide tube connecting tube, an upper tube seat and a fuel assembly skeleton. The guide tube connecting tube of the present invention is a hollow cylinder with open upper and lower end faces, and its inner diameter matches the outer diameter of the guide tube. The lower part of the guide tube connecting tube is expanded and connected to the outside of the guide tube, and the upper part of the guide tube connecting tube is provided with a plurality of protrusions along the circumferential direction; the upper tube seat of the present invention includes a clamping spring and a tube seat, and a plurality of slide grooves are provided at the inner wall of the channel where the tube seat needs to be connected to the guide tube, a spring is provided at the end of the slide groove, a block is connected in front of the spring, and a depression is provided under the block in the slide groove. The present invention has a simple structure, is easy to install, and effectively overcomes the problem that the connection mechanism between the guide tube and the upper tube seat in the prior art is easy to loosen, and significantly improves the safety and reliability of the fuel assembly.

A curvilinear electromagnetic pump is configured to follow a curve, such as by joining together multiple linear pump segments offset at an angle relative to one another. A curvilinear electromagnetic pump can be curved in two dimensions or in three dimensions. A curvilinear electromagnetic pump allows for more efficient placement of components and systems within a reactor vessel, significantly reducing the height of the reactor vessel compared to vertically positioned linear pumps. A curvilinear electromagnetic pump can follow the curvature of the reactor vessel wall and can be positioned generally near the bottom of the reactor vessel.

The reactor is designed to couple the load paths of the control elements with the core, thereby reducing the possibility of differential motion between the control elements and the core. A cartridge core barrel may be manufactured at a manufacturing facility to include the core, control element supports, and control element drive systems. The cartridge core barrel may be attached to the reactor vessel head so that any motion (e.g., via seismic forces) is transmitted to the control elements and the core with equal direction and magnitude, thereby reducing the possibility of differential motion.