Abstract: In view of above problems, an object of the invention is to provide a primary containment vessel venting system having a structure capable of continuously discharging vapor in a primary containment vessel out of the system and continuously reducing pressure of the primary containment vessel without discharging radioactive noble gases to the outside of the containment vessel and without using an enclosing vessel or a power source. In order to achieve the above object, an nuclear power plant of the invention includes a primary containment vessel which includes a reactor pressure vessel, a radioactive substance separation apparatus which is disposed inside the primary containment vessel and through which the radioactive noble gases do not permeate but vapor permeates, a vent pipe which is connected to the radioactive substance separation apparatus, and an exhaust tower which is connected to the vent pipe and discharges a gas, from which a radioactive substance is removed, to the outside.

Abstract: In view of above problems, an object of the invention is to provide a primary containment vessel venting system having a structure capable of continuously discharging vapor in a primary containment vessel out of the system and continuously reducing pressure of the primary containment vessel without discharging radioactive noble gases to the outside of the containment vessel and without using an enclosing vessel or a power source. In order to achieve the above object, an nuclear power plant of the invention includes a primary containment vessel which includes a reactor pressure vessel, a radioactive substance separation apparatus which is disposed inside the primary containment vessel and through which the radioactive noble gases do not permeate but vapor permeates, a vent pipe which is connected to the radioactive substance separation apparatus, and an exhaust tower which is connected to the vent pipe and discharges a gas, from which a radioactive substance is removed, to the outside.

Abstract: A gas turbine combustor achieves improved product reliability and a reduced increase in pressure loss through improvements made on a cooling characteristic and structural intensity. The structure of the gas turbine combustor includes a plurality of circularity recesses formed on a side of an annular passage on a partial area of a combustion liner that requires cooling. Each of the circularity recesses has a rectangular surface forming a convex at a right angle with respect to a flowing direction of combustion air. The circularity recesses form a rectangular triangle having an oblique surface facing upstream of the flowing direction of the combustion air.

Abstract: There is provided a gas turbine combustor that achieves improved product reliability and a reduced increase in pressure loss through improvements made on a cooling characteristic and structural intensity. A gas turbine combustor structure includes a plurality of circularity recesses 20 formed on a side of an annular passage 11 on a partial area of a combustion liner 8 that requires cooling. The circularity recesses 20 each have a rectangular surface 25 forming a convex at a right angle with respect to a flowing direction of combustion air 2. The circularity recesses 20 is a rectangular triangle having an oblique surface 26 facing upstream of the flowing direction of the combustion air 2.

Abstract: In an indirect cycle nuclear reactor, a size of the reactor containment vessel is decreased by removing decay heat inside the reactor pressure vessel without using any active component to improve the economic feasibility. A main steam pipe communicating with a heat exchanger of the indirect cycle nuclear reactor is branched in a position upstream of a main steam isolation valve to connect the branched pipe to a heat exchanger in a pressure suppression pool through an isolation valve. A feed water pipe is also branched in a position upstream of an isolation valve to connect the branched pipe to the heat exchanger through the isolation valve. Decay heat is dissipated from the heat exchanger into the pressure suppression pool, and condensed water condensed by heat dissipation is returned to the heat exchanger to cool the inside of the pressure vessel.

Abstract: In an indirect cycle nuclear reactor, size of the reactor containment vessel is decreased by removing decay heat inside the reactor pressure vessel without using any active component to improve the economic feasibility.

Abstract: Improved operability and economy of a nuclear reactor can be obtained by attaining a mixing of the flows of coolant in the lower plenum of the fuel assemblies of the nuclear reactor, a high flow stability of the two-phase flow in the fuel assemblies and a small pressure loss in the core. To achieve this, there is provided a coolant guide tube 60 that communicates with the inside of the fuel support piece 12 inserted in the control rod guide tube and the passage 16, wherein there is formed a coolant guide passage 61 along which coolant descends in the area outside of the coolant guide tube in the fuel assemblies from opening 79. The coolant guide passage along which the coolant descends from the opening is formed in an area outside of the coolant guide tube in the fuel support piece.

Abstract: A reactor containment facility having a reactor pressure vessel containing a core; a dry well in which the reactor pressure vessel is arranged; a suppression chamber holding suppression-pool water and forming above the suppression-pool water a wet well; and a plurality of vent pipes allowing the dry well to communicate with the suppression-pool water; a steel wall which is in contact with the suppression-pool water of the suppression chamber and which surrounds at least the pool water so as to form a containment vessel which houses the dry well and the suppression chamber; and an outer peripheral pool containing cooling water in contact with the outer peripheral surface of the steel wall.

Abstract: There is disclosed a nuclear reactor installation. An accumulator-type emergency core cooling system, a gravity-driven core cooling system and an equalizing system for submerging a reactor core are provided within a primary containment vessel containing a reactor pressure vessel in which the reactor core is disposed. These cooling systems are automatically operated sequentially in accordance with the pressure in the reactor pressure vessel without the need for any particular powered source. The primary containment vessel is made of steel, and the interior of this containment vessel is divided into a space containing the reactor pressure vessel and a space containing an operation floor in such a manner that the two spaces are isolated from each other.

Abstract: In a boiling water nuclear reactor, a reactor primary cooling water line is filled with water at the start-up time, and the inside of a pressure vessel is pressurized by a pressurized tank and at the same time control rods are withdrawn to thereby heat cooling water in a state of single-phase flow to high temperature. Succeedingly, the pressurization is released and the pressure of the pressure vessel is gradually approximated to the saturation pressure corresponding to the cooling water temperature to thereby make the cooling water transit into a state of two-phase flow, and thereafter the cooling water is heated by nuclear reaction in the state of two-phase flow to thereby obtain predetermined reactor running temperature and pressure.