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

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

The technical result is achieved by using the membraned, drum and thermal protection installed in the area between the layered vessel and cantilever truss in the corium localizing and cooling system of a nuclear reactor.

A radioactive nuclear waste storage system includes a cask comprising a hermetically sealed internal cavity configured for holding the waste such as spent nuclear fuel submerged in an inventory of water. One or more pressure surge capacitors disposed inside the cask include a vacuum cavity evacuated to sub-atmospheric conditions prior to storage of fuel in the cask. At least one rupture disk seals a vacuum chamber inside each capacitor. Each rupture disk is designed and constructed to burst at a predetermined burst pressure level occurring inside the cask external to the capacitor. This allows excess cask pressure occurring during a high pressure excursion resulting from abnormal operating conditions to bleed into capacitor, thereby returning the pressure inside the cask to acceptable levels. In one embodiment, the capacitors are located in peripheral regions of the cask cavity adjacent to the circumferential wall of the cask body.

Nuclear fuel structures and methods for fabricating are disclosed herein. The nuclear fuel structure includes a plurality of fibers arranged in the structure and a multilayer fuel region within at least one fiber of the plurality of fibers. The multilayer fuel region includes an inner layer region made of a nuclear fuel material, and an outer layer region encasing the nuclear fuel material. A plurality of discrete multilayer fuel regions may be formed over a core region along the at least one fiber, the plurality of discrete multilayer fuel regions having a respective inner layer region of nuclear fuel material and a respective outer layer region encasing the nuclear fuel material. The plurality of fibers may be wrapped around an inner rod or tube structure or inside an outer tube structure of the nuclear fuel structure, providing both structural support and the nuclear fuel material of the nuclear fuel structure.

A neutron absorbing insert for use in a fuel rack. In one aspect, the insert includes: a plate structure having a first wall and a second wall that is non-coplanar to the first wall; the first and second walls being formed by a single panel of a metal matrix composite having neutron absorbing particulate reinforcement that is bent into the non-coplanar arrangement along a crease; and a plurality of spaced-apart holes formed into the single panel along the crease prior to bending.

Disclosed are a simulation platform and a simulation method for leakage detection and treatment. The simulation platform includes a water tank open at the top, which is a holding device; simulation sand, which is laid at the bottom of the water tank, and the upper area of the simulation sand is the experimental water filling area for filling simulation water; a leakage simulation device, which is buried in the simulation sand; a plurality of electrodes, which are distributed on the simulation sand for collecting and sending potential and current signals to a data processing terminal; a hydraulic brake, which is arranged in the experimental water filling area and used for stirring the simulation water; the hydraulic brake is not turned on in the static water environment simulation, and is turned on in the dynamic water environment simulation.

The present invention relates to a stop valve for installation in a pipeline, in particular in a pipeline of a nuclear facility, such as a nuclear power plant, or in a conventional chemical reactor and in a conventional power plant, to stop a fluid flow through the pipeline in the event of an operational failure. The valve comprises a valve housing including a flow channel passing through the valve housing, and a closure member arranged at least partially in the flow channel and reversibly transferable between an open position and a closed position such as to open or close the flow channel through the valve housing. The valve further comprises a non-electrically driven actuator mechanism operatively coupled to the closure member for transferring the closure member at least from the open position in the closed position. The actuator mechanism is configured to be activated by a fluid flow through the flow channel reaching or exceeding a switching temperature and/or switching flow rate during operation. In addition, the valve comprises at least one position indicator to indicate whether the closure member is in the open position or in the closed position. The position indicator comprises at least one indicator member movably arranged in or at the valve housing between a first position and a second position, wherein the indicator member is magnetically coupled to the closure member such that the indicator member is magnetically transferred into the first position when the closure member is transferred into the open position, and into the second position when the closure member is transferred into the closed position.

A sensor assembly for determining an operating characteristic of a nuclear reactor. The sensor assembly includes a solid-state lasing media doped with a fissile species and disposable within a core of the nuclear reactor and an optical fiber operably coupled to the solid-state lasing media and configured to extend out of the core of the nuclear reactor and to control system of reactor. The fissile species include one or more of uranium, plutonium, americium, or californium. A method of determining an operating characteristic of a nuclear reactor includes during operation of the nuclear reactor; receiving from the optical fiber a laser light, analyzing the laser light, and based on the analysis of the laser light, determining the operating characteristic of the nuclear reactor.

A nuclear reactor core includes a plurality of fuel elements and a skewed-pin moderator block array of skewed-pin 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 inner holes are irregularly spaced with respect to the outer holes.

This antivibration sound insulation device is provided with: an antivibration mechanism which is mounted on a stand and disposed close to a prescribed sound source at a plant; and sound-absorbing sound insulation walls which are supported by the antivibration mechanism and arranged so as to surround the sound source.

The disclosure relates to a flexible automatic clamping device and method for backside laser penetration welding of a T-shaped structure. The flexible automatic clamping device includes a clamping system, a ranging system and a control system. The ranging system outputs a position instruction to the control system, the control system outputs a movement instruction to the clamping system, so as to adjust the clamping system to an optimal position, then a stringer pressing plate fastens a stringer by means of a Y-shaped connecting rod, and a skin pressing plate fastens skin by means of a skin connecting rod. Based on the flexible automatic clamping device, the method includes prewelding clamping, backside laser penetration welding and postwelding shape retention. The disclosure implements accurate positioning, automatic clamping, backside laser penetration welding and postwelding shape retention of a T-shaped skin-stringer structure.