Abstract: 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.

Abstract: A nuclear reactor shutdown system includes a housing vessel that is disposed above a reactor core fuel housed in a nuclear core vessel in a hermetically sealed manner, houses a plurality of neutron absorbers, and has an opening enabling the neutron absorbers to pass through at a bottom, a shielded path that passes through the reactor core fuel to extend in an up-and-down direction, an upper end of the shielded path communicating with the opening of the housing vessel and a lower end of the shielded path being closed, and a communicating part that is disposed so as to close the opening and causes the housing vessel and the shielded path to communicate with each other when the communicating part reaches or exceeds a threshold temperature.

Abstract: A nuclear reactor shutdown system includes a shielded path that passes through a reactor core fuel housed in a nuclear reactor vessel in a hermetically sealed manner, one end of the shielded path having an opening and another end of the shielded path being closed; a neutron absorber that is allowed to enter from the opening of the shielded path; an elastic member that is configured to urge the neutron absorber in a direction entering inside from the opening of the shielded path by being released from a compressed state; and a braking part that is disposed so as to maintain the compressed state of the elastic member and is configured to release the elastic member from the compressed state when the braking part reaches or exceeds a threshold temperature.

Abstract: An easy-to-construct nuclear reactor shielding facility with robust shielding against ionizing radiation is provided. This nuclear reactor shielding facility is a nuclear reactor shielding facility for shielding a nuclear reactor installed on an installation surface by enclosing the nuclear reactor, and includes: a base structure that is disposed around an outer surface of the nuclear reactor except for the installation surface, and encloses an entire surface of the nuclear reactor except for the installation surface; and a shielding structure that is disposed on an entire surface of the base structure and internal of which is filled with water.

Abstract: An object is to change reactor core thermal output. A nuclear reactor includes an annular fuel layer and a heat conductive layer stacked on the fuel layer and extending around a periphery of the fuel layer.

Abstract: An object is to efficiently take heat out of a reactor core while retaining fission products. Included are fuel part provided with a covering part on a surface of a nuclear fuel and a heat conductive part.

Abstract: Provided is a nuclear reactor unit that can reduce a temperature increase in a reactor core at the occurrence of an abnormality with a simple structure. Included are a reactor core having radioactive fuel and causing the radioactive fuel to cause a nuclear reaction and a nuclear reactor vessel housing the reactor core and hermetically sealing the reactor core. The nuclear reactor vessel includes an inner shroud covering the entire periphery of the reactor core and an outer shroud covering the entire periphery of the inner shroud. A first space formed by the outer shroud and the inner shroud is in a vacuum condition. The inner shroud includes a main body and a communicating part placed in part of the main body and communicating the first space to a second space, which is a space inside the inner shroud, when the reactor core reaches a threshold temperature or higher.

Abstract: Heat can be stably extracted with easy criticality control. A nuclear reactor includes: a fuel portion being a reactor core having a nuclear fuel body; a shielding portion covering all over outer sides of the fuel portion to shield against radiations generated from the reactor core; and a thermal conduction part that conducts heat generated in the reactor core to exterior of the shield part. The nuclear fuel body contains a fissile material with an enrichment not less than 5% by weight throughout an operation period.

Abstract: Ensuring a high output temperature while preventing leakage of radioactive substances, etc. A nuclear reactor includes a fuel unit; a shield unit that covers a circumference of the fuel unit for shielding from radioactive rays; and a heat conductive portion that penetrates the shield unit, is arranged such that the heat conductive portion extends to inside of the fuel unit and outside of the shield unit, and transfers heat of the fuel unit to the outside of the shield unit by solid heat conduction.

Abstract: A nuclear power generation system includes a nuclear reactor that includes a reactor core fuel and a nuclear reactor vessel, the nuclear reactor vessel covering a surrounding of the reactor core fuel, shielding a space in which the reactor core fuel is present, and shielding radioactive rays; a heat conductive portion that is disposed in at least a part of the nuclear reactor vessel to transfer heat inside the nuclear reactor vessel to an outside by solid heat conduction; a heat exchanger that performs heat exchange between the heat conductive portion and a refrigerant; a refrigerant circulation unit that circulates the refrigerant passing through the heat exchanger; a turbine that is rotated by the refrigerant circulated by the refrigerant circulation unit; and a generator that rotates integrally with the turbine.

Abstract: An inspection apparatus for inspecting a workpiece having an outer peripheral portion rotationally symmetric about a symmetry axis with projections and recesses provided periodically and repeatedly, the apparatus comprises: an edge imaging mechanism that captures an image of an edge portion of a projection of a rotated workpiece; an upstream imaging mechanism that captures an image of an upstream wall surface of the rotated workpiece; and a downstream imaging mechanism that captures an image of a downstream wall surface of the rotated workpiece. The inspection apparatus inspects the workpiece on the basis of the images captured by the edge imaging mechanism, the upstream imaging mechanism, and the downstream imaging mechanism.

Abstract: An inspection apparatus includes: an upstream imaging mechanism that images an upstream wall surface extending from a bottom part of a recess upstream of and adjacent to a projection in a rotating direction of a workpiece to a tip of the projection; and a downstream imaging mechanism that images a downstream wall surface extending from a bottom part of the recess downstream of and adjacent to the projection in the rotating direction to the tip of the projection. At least one of the imaging mechanisms includes a mover for parallelly moving and positioning in an orthogonal plane orthogonal to the axis of symmetry and images the workpiece from a position radially outward of the workpiece and positioned by the mover.

Abstract: An inspection apparatus includes: an upstream imaging mechanism that images an upstream wall surface extending from a bottom part of a recess upstream of and adjacent to a projection in a rotating direction of a workpiece to a tip of the projection; and a downstream imaging mechanism that images a downstream wall surface extending from a bottom part of the recess downstream of and adjacent to the projection in the rotating direction to the tip of the projection. At least one of the imaging mechanisms includes a mover for parallelly moving and positioning in an orthogonal plane orthogonal to the axis of symmetry and images the workpiece from a position radially outward of the workpiece and positioned by the mover.

Abstract: An inspection apparatus for inspecting a workpiece having an outer peripheral portion rotationally symmetric about a symmetry axis with projections and recesses provided periodically and repeatedly, the apparatus comprises: an edge imaging mechanism that captures an image of an edge portion of a projection of a rotated workpiece; an upstream imaging mechanism that captures an image of an upstream wall surface of the rotated workpiece; and a downstream imaging mechanism that captures an image of a downstream wall surface of the rotated workpiece. The inspection apparatus inspects the workpiece on the basis of the images captured by the edge imaging mechanism, the upstream imaging mechanism, and the downstream imaging mechanism.