Abstract: A method of releasing an atmospheric effluent within a nuclear containment to an atmosphere surrounding the nuclear containment is disclosed. The nuclear containment is adjacent to an associated spent fuel pool that is located outside the nuclear containment, the method comprises sensing a pressure buildup within the nuclear containment, routing a portion of the atmospheric effluent through the spent fuel pool when a pressure buildup within the nuclear containment reaches a preselected value, and releasing a chemical into the spent fuel pool, based on the routing, to facilitate a reaction with the atmospheric effluent to substantially neuter any deleterious environmental impact of the atmospheric effluent.

Abstract: A power generating machine system is connected to the thermodynamic field similar to a steam power plant that can be used both mobile and in a fixed manner, which uses fluid liquid nitrogen and/or liquid air mixture and atmosphere air as an energy source. The power generating machine system is not harmful to the environment.

Abstract: An anti-surge recycle valve system for a natural gas line using a pipeline rotary control valve for controlling gas flow through the gas line and a valve controller having a surge-programmable feature including a threshold setpoint deviation limit, which is used to control first and second control valve loops. The first solenoid valve loop drives a rotary high-pressure piston actuator when the linear position sensor determines a setpoint deviation in gas flow below the threshold deviation, and the second solenoid valve loop drives the rotary high-pressure piston actuator when the linear position sensor determines a setpoint deviation in gas flow above the threshold deviation. The system provides ultra-rapid stroking speed in tandem with highly accurate and stable positioning.

Abstract: A system of Structural Members that interconnect or attach to each other to create an Outer Structural Shell to strengthen and protect against failure of Reactor Containment/Shield Buildings and other concrete structures or supports such as pillars, columns and piers. When interconnected, the Structural Members are tensioned to create a protective Outer Structural Shell to contain and restrict degraded or cracked concrete from further cracking and eventual delamination, by applying a supportive compression force to outer concrete wall(s) and surfaces.

Abstract: Aspects of the present disclosure relate to electromagnetic vaporizer assembly, electronic cigarette having electromagnetic vaporizer assembly, and methods of using the same. In certain embodiments, electromagnetic vaporizer assembly includes: an electromagnetic vaporizer, and an electromagnetic heating controller. Electromagnetic vaporizer includes an electromagnetic heating coil to heat a cigarette. Electromagnetic heating controller allows a user to control and use an electronic cigarette having electromagnetic vaporizer assembly. When user inserts the cigarette into a cigarette holder, and presses a push button, the electromagnetic heating controller provides a predetermined AC voltage to the electromagnetic heating coil to heat up the cigarette, and the user enjoys vaporized cigarette.

Abstract: A multi-modular power plant may include a plurality of on-site nuclear power modules configured to generate a power plant output, wherein one or more of the nuclear power modules may be designated as service module units which are configured to generate a first portion of the power plant output. A remainder of the nuclear power modules may be configured to generate a second portion of the power plant output. A number of power plant systems may be configured to operate using electricity associated with a house load of the power plant, wherein the first portion of the power plant output is equal to or greater than the house load. Additionally, a switchyard may be configured to electrically connect the power plant to a distributed electrical grid. The distributed electrical grid may be configured to service a plurality of geographically distributed consumers, and the switchyard may be configured to apply the second portion of the power plant output to the distributed electrical grid.

Abstract: A system for removing the residual power of a pressurized water nuclear reactor, includes a reserve of water, a steam generator, wherein the primary water heated by the core either circulates in a forced manner during power operation, or circulates naturally when the primary pump is stopped, and a condenser housed in the containment vessel. The condenser includes a recovery unit for recovering the condensed water and a condenser link to ensure the circulation of water in a closed circuit between the reserve and the condenser. The system further includes a device for circulating the secondary water between the steam generator and the condenser, the device being activated without an external supply of electrical energy, when an operating parameter characteristic of excessive heating of the primary water reaches a certain threshold, such that the primary water heated by the core and circulating in the steam generator vaporizes the secondary water.

Abstract: A radiation monitor includes an AC control section and a DC control section. The AC control section outputs an AC power source instantaneous power failure detection signal to the DC control section when a decrease in AC voltage is detected. The DC control section measures a duration time of an AC power source instantaneous power failure detection signal when the AC power source instantaneous power failure detection signal is received from the AC control section and outputs an instantaneous power failure restart signal to the AC control section if the AC voltage is restored within a time shorter than a set value. The AC control section performs switching control from close to open of the sampling solenoid valve, the purge solenoid valve, and the exhaust solenoid valve, and restarts the pump after a constant time when the instantaneous power failure restart signal is received from the DC control section.

Abstract: Example embodiments provide a Basemat-Internal Melt Arrest and Coolability device (BiMAC) that offers improved spatial and mechanical characteristics for use in damage prevention and risk mitigation in accident scenarios. Example embodiments may include a BiMAC having an inclination of less than 10-degrees from the basemat floor and/or coolant channels of less than 4 inches in diameter, while maintaining minimum safety margins required by the Nuclear Regulatory Commission.

Abstract: A nuclear fuel cladding is provided. The nuclear fuel cladding includes a base cladding; and at least one nanomaterial layer deposited on a surface of the base cladding, the nanomaterial layer having an average grain size of between 5 to 400 nanometers. A method of manufacturing nuclear fuel cladding is also provided. The method includes depositing nanoparticles on a base cladding to form at least one nanomaterial layer, the nanoparticles having an average grain size of between 5 to 400 nanometers.

Abstract: There is provided a holding device which can hold a molten corium for a predetermined period even when the molten corium is exposed to heat or undergoes any chemical reaction and which is applicable to practical use. There is provided a holding device provided below a nuclear reactor pressure vessel for holding a molten corium, wherein the holding device includes a base material in contact with a cooling medium, and a multilayer stack structure on the base material. The multilayer stack structure has a first layer having heat-resistant property, a second layer formed on the first layer and having heat-resistant property with lower heat conductivity than that of the first layer, and a third layer formed on the second layer and having corrosion-resistant property and impact-absorbing property.

Abstract: A gas supply apparatus of the present invention includes: an operating valve that is placed in the middle of a piping for letting at least gas in a plant flow and that operates a valve main body by the gas flowing in the piping; a first electromagnetic valve that is placed in the middle of the piping and that opens or closes a flow of the gas to the operating valve; and a gas supply source that supplies the first electromagnetic valve with the gas. A gas discharge line of the first electromagnetic valve has a switching valve placed therein and has a second electromagnetic valve placed between the switching valve and the gas supply source. The switching valve switches between a gas discharge from the first electromagnetic valve and a gas supply to the first electromagnetic valve. When a power source is lost, the switching valve is switched to connection to the gas supply source so as to supply the first electromagnetic valve with the gas.

Abstract: A nuclear steam supply system utilizing gravity-driven natural circulation for primary coolant flow through a fluidly interconnected reactor vessel and a steam generating vessel. In one embodiment, the steam generating vessel includes a plurality of vertically stacked heat exchangers operable to convert a secondary coolant from a saturated liquid to superheated steam by utilizing heat gained by the primary coolant from a nuclear fuel core in the reactor vessel. The secondary coolant may be working fluid associated with a Rankine power cycle turbine-generator set in some embodiments. The steam generating vessel and reactor vessel may each be comprised of vertically elongated shells, which in one embodiment are arranged in lateral adjacent relationship. In one embodiment, the reactor vessel and steam generating vessel are physically discrete self-supporting structures which may be physically located in the same containment vessel.

Abstract: Disclosed is a coolant with dispersed neutron poison micro-particles, used in a supercritical water-cooled reactor (SCWR) emergency core cooling system. Since the neutron poison micro-particles are uniformly dispersed in the coolant of the emergency core cooling system for a long period time, their fluidity is not lowered even though the polarity of water is changed in a supercritical state. Therefore, the neutron poison micro-particles absorb neutrons produced from nuclear fission in a nuclear reactor core. Accordingly, the neutron poison micro-particles can be appropriately used as a means for controlling neutrons and stopping a nuclear reactor in the SCWR emergency core cooling system.

Abstract: A nuclear power plant with an improved cooling system using nanoparticles in solid or fluid form is provided. The nanoparticles are delivered in locations such as the cold leg accumulator and high and low pressure pumps of an emergency core cooling system. Motor driven valves and pressurization can aid in the delivery. Methods for providing the nanoparticles are also provided.

Abstract: Filtering systems and methods remove debris from coolant in a nuclear reactor setting. One or more filters are installed outside coolant reservoirs specifically where coolant will flow toward the reservoir, such as during a transient or other coolant leak event. Useable filters permit coolant through-flow while catching, straining, diverting, or otherwise removing debris from the coolant without significant interference with the coolant flow. Filters can be installed at any location in a flow path for coolant flowing toward the reservoir, including pipes draining into a suppression pool, floor or personnel platform gratings, areas around main steam legs or steam generators, in a reactor drywell, etc. One or more filters are installed by securing the filter in a coolant flow path into a coolant source. Installation and maintenance can be performed during any maintenance period.

Abstract: Internal head vents are usable in nuclear reactors and include piping inside of the reactor pressure vessel with a vent in the reactor upper head. Piping extends downward from the upper head and passes outside of the reactor to permit the gas to escape or be forcibly vented outside of the reactor without external piping on the upper head. The piping may include upper and lowers section that removably mate where the upper head joins to the reactor pressure vessel. The removable mating may include a compressible bellows and corresponding funnel. The piping is fabricated of nuclear-reactor-safe materials, including carbon steel, stainless steel, and/or a Ni—Cr—Fe alloy. Methods install an internal head vent in a nuclear reactor by securing piping to an internal surface of an upper head of the nuclear reactor and/or securing piping to an internal surface of a reactor pressure vessel.

Abstract: A system and method isolate a nuclear power plant from effects of seismic action. An artificial lake is formed as a depressed area in the ground surrounded by walls or banks to constrain a volume of water within the depressed area. The lake has a concrete reinforced bed. The lake is surrounded by a land-based support area. The lake is filled from a source of water in liquid communication with the lake. The source is controlled to release water into the lake to maintain the lake at a selected level. At least one vessel floats on the surface of the water. The vessel is connected to the walls or banks of the lake with a plurality of shock absorbers to dampen movement of the vessel. A nuclear power plant erected on the vessel includes at least one cooling tower that receives cooling water from the lake.

Abstract: A nuclear reactor includes a pressure vessel and a nuclear reactor core disposed in the pressure vessel. A subterranean containment structure contains the nuclear reactor. An ultimate heat sink (UHS) pool is disposed at grade level, and an upper portion of the subterranean containment structure defines at least a portion of the bottom of the UHS pool. In some embodiments, the upper portion of the subterranean containment structure comprises an upper dome, which may protrude above the surface of the UHS pool to define an island surrounded by the UHS pool. In some embodiments, a condenser comprising a heat exchanger including hot and cold flow paths is disposed inside the subterranean containment structure; and cooling water lines operatively connect the condenser with the UHS pool.

Abstract: An earthquake-resistant reinforcement assembly according to one embodiment of the present invention comprises: a rod of which one end is hinge-coupled to an upper structure; a combination pin which is formed at the other end of the rod and is extended to diametrically cross the rod; and a bracket which is provided on a partition wall of a nuclear reactor containment building and is coupled with the other end, wherein the bracket can withstand a tensile load and a torsional load by including first and second members which face each other and are extended in parallel to load the rod thereon, and groove portions which are formed at the first and second members to be coupled with the combination pin to form the shape of a double bracket.

Abstract: Exemplary embodiments provide automated nuclear fission reactors and methods for their operation. Exemplary embodiments and aspects include, without limitation, re-use of nuclear fission fuel, alternate fuels and fuel geometries, modular fuel cores, fast fluid cooling, variable burn-up, programmable nuclear thermostats, fast flux irradiation, temperature-driven surface area/volume ratio neutron absorption, low coolant temperature cores, refueling, and the like.

Abstract: Heat from an ex-vessel mass of core material is removed to cooler regions of a containment envelope via liquid and/or vapor phase transport. Various aspects provide for contacting the ex-vessel core material with a material having properties including melting point, boiling point, and condensation kinetics such that condensation of the material in cooler regions of the containment envelope is at least as fast as evaporation of the material due to heat absorption from the core material and associated species.

Abstract: A nuclear reactor module includes a reactor vessel and a reactor housing mounted inside the reactor vessel, wherein the reactor housing comprises a shroud and a riser located above the shroud. The nuclear reactor module further includes a heat exchanger proximately located about the riser, and a reactor core located in the shroud. A steam generator by-pass system is configured to provide an auxiliary flow path of primary coolant to the reactor core to augment a primary flow path of the primary coolant out of the riser and into the shroud, wherein the auxiliary flow path of primary coolant exits the reactor housing without passing by the heat exchanger.

Abstract: According to an embodiment, a pressurized water reactor plant has a primary system which includes: a reactor vessel for housing a reactor core which is cooled by a primary coolant, a single steam generator, a hot leg pipe for connecting the reactor vessel and the steam generator, cold leg pipes, at least two primary coolant pumps, and a pressurizer for pressurizing the primary coolant pressure boundary in which the primary coolant flows. The plant also has: a passive cooling and depressurization system which is a primary depressurization means for equalizing the primary system pressure to the secondary system pressure at the time of a tube rupture accident of the steam generator, and a reactor containment vessel containing the primary system and cooling the primary system by air cooling. Thus, a compact pressurized water rector with high economic efficiency, safety, and reliability can be provided.

Abstract: An integrated reactor missile shield and crane assembly (IRMSCA) is disclosed and claimed. The IRMSCA replaces the existing concrete missile shields and reactor services crane. The IRMSCA is moveable such that the missile shield can be moved away from the reactor head, allowing the integral crane to lift the control rod drive mechanism components and other routine loads at the refueling cavity.

Abstract: A system and method for assessing failure of fuel rods are disclosed. The method may include monitoring fuel rod operational conditions, comparing the fuel rod parameters to parameters limits, calculating the fuel rod performance parameters to determine the likelihood of failure of individual fuel rods, and updating plant operating parameters based on the calculated fuel rod parameters. The system may input the calculated fuel rod parameters into a fuel failure model to assess the probability of failure, and predict the probability of failure of individual fuel rods based on fuel rod parameters in the fuel failure model.

Abstract: A radiation exposure reduction method includes the steps of: injecting iron into a coolant which flows from the reactor cooling system to the reactor core in a nuclear power plant; and ferritizing and fixing radionuclides or parent nuclides thereof, which are contained in the coolant, on the surface of a reactor core structure, wherein an iron citrate which is soluble organic iron, or iron oxalate or iron fumarate which has a particle diameter of 3 ?m or less, is used as the iron to be injected into the coolant.

Abstract: There is provided a fuel rod assembly comprising a first component of a zirconium-based material. The first component is in contact with or is located adjacent to a second component of a material different from the zirconium-based material, e.g. a nickel-based or iron-based alloy. A coating is disposed on an outer surface of the first component, which is effective to reduce an electrochemical corrosion potential difference between the first component and the second component relative to an electrochemical corrosion potential difference between the first component and the second component without the coating.

Abstract: Illustrative embodiments provide systems, methods, apparatuses, and applications related to annealing nuclear fission reactor materials.

Abstract: A device for detecting steel is provided. The steel is used in a nuclear plant. The device has a detecting circuit of electrochemical corrosion potential (ECP) and alternative current (AC) impedance. An environment in a boiling water reactor (BWR) is simulated under hydrogen water chemistry (HWC). The environment is used for detecting intergranular stress corrosion cracking (IGSCC) of components coated with different precious metals. Thus, effect of coating different precious metals on steels can be evaluated for HWC.

Abstract: Nuclear reactor systems and methods are described having many unique features tailored to address the special conditions and needs of emerging markets. The fast neutron spectrum nuclear reactor system may include a reactor having a reactor tank. A reactor core may be located within the reactor tank. The reactor core may include a fuel column of metal or cermet fuel using liquid sodium as a heat transfer medium. A pump may circulate the liquid sodium through a heat exchanger. The system may include a balance of plant with no nuclear safety function. The reactor may be modular, and may produce approximately 100 MWe.

Abstract: A power module assembly includes a reactor vessel containing a reactor core surrounded by a primary coolant. A containment vessel is adapted to be submerged in a containment cooling pool and to prohibit a release of the primary coolant outside of the containment vessel. A secondary cooling system is configured to remove heat generated by the reactor core. The heat is removed by circulating liquid from the containment cooling pool through the primary coolant.

Abstract: An apparatus for reinforcing a jet pump riser includes: an elbow upper clamp for covering a riser elbow coupled to a thermal sleeve from an upper side thereof; an elbow lower clamping member for clamping the riser elbow from a lower side thereof; an elbow vertical portion clamping member for covering a vertical portion of the riser elbow; and an elbow horizontal portion clamping member for covering a horizontal portion of the riser elbow. These members are disposed in different orientations with respect to the elbow upper clamp so as to fix the thermal sleeve, the riser elbow and the riser pipe.

Abstract: In a nuclear reactor building of a steel plate concrete structure that houses a pressure containment vessel formed with a plurality of penetration ports penetrating the pressure containment vessel on the periphery thereof and includes a biological shielding wall disposed outside the pressure containment vessel. The pressure containment vessel is vertically divided into a plurality of blocks so that each of the blocks has one or more pressure containment vessel penetration ports arranged on a same horizontal plane, and the reactor building including the biological shielding wall is divided into a plurality of modules by the horizontal plane.

Abstract: In a cooling structure and a cooling method for a control rod drive mechanism and in a nuclear reactor, a housing (59) in which magnetic jacks are housed is fixed to an upper portion of a reactor vessel (41), and an air intake unit (102) that takes cooling air into the housing (59), a first exhaust duct (104) that is arranged side by side with the air intake unit (102) in a circumferential direction of the housing (59), into which cooling air in the housing (59) is suctioned through a first inlet (109) at a lower portion thereof, and that guides the cooling air upward, a second exhaust duct (105) that is disposed below the air intake unit (102), into which cooling air in the housing (59) is suctioned through a second inlet (110), and that guides the cooling air to the first exhaust duct (104), and a discharging unit (111) that is formed at an upper portion of the housing (59) and discharges cooling air in the first exhaust duct (104) to the exterior are provided.

Abstract: A surface conditioning scheduling process is used to mitigate susceptibility to crack initiation or crack growth in a boiling water nuclear reactor using a plurality of working crews. A plurality of working zones are defined in an annulus region of a reactor vessel flange, and a plurality working zones are defined in a core region of the reactor vessel. One of the working crews is positioned in each of the annulus region working zones, and one of the working crews is positioned in each of the core region working zones. The working crews perform surface conditioning in areas of the reactor vessel accessible from their respective working zones such that the surface conditioning process can be completed in no more than thirty days.

Abstract: The present invention relates to tubular elements, such as fuel assembly tubes, which are designed to be used in high pressure and high temperature water in nuclear reactors, such as pressurized water nuclear reactors. In particular, the present invention relates to a method of improving wear resistance and corrosion resistance by depositing a protective coating having a depth of from about 5 to about 25 ?m on the surface of the tubular elements. The coating is provided by nitriding the tubular element at a temperature of from about 400° C. to about 440° C. The nitridation of the tubular element can be carried out for a duration of from about 12 hours to about 40 hours.

Abstract: A computer-implemented system and method for managing operations in a nuclear power plant generates an electronic request for a permit to perform work in the plant, performs a risk assessment using a rules engine to determine a level of fire risk posed by the work, automatically determines one or more compensatory measures to provide protection against the level of fire risk posed by work, generates a risk score based the probabilistic assessment, and generates electronic authorization for the permit based on the risk score.

Abstract: The invention relates to a method and an arrangement for providing an emergency supply to a nuclear installation. The arrangement comprises a container (10) with a plurality of permanently installed devices and at least one motor (22), one generator (26), one pump (24), one fuel tank (14) and one transformer (34), wherein the pump and the generator are functionally connected to the motor in order to activate said motor.

Abstract: The present invention provides a method of manufacturing a core shroud for a nuclear plant and a nuclear power plant structure in which a groove portion is easily assembled in the case of manufacturing the core shroud having a weld structure of a nuclear power plant by a laser welding, and it is possible to obtain a weld joint portion in which a plastic distortion region and a residual stress are as small as possible, going with a solidification shrinkage of the weld portion. At a time of welding butted portions of a plurality of members constructing a core shroud, a root face is provided in the butted portion, a length of the root face is set to 25% to 95% of a thickness of the thinner one of the butted portions of a plurality of members, a narrow groove is provided in the other than the root face, and the butted portions are welded by a laser welding using a weld wire.

Abstract: A neutron absorbing insert for use in a fuel rack and method of manufacturing the same. In ones aspect, the invention is a neutron absorbing apparatus comprising: 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.

Abstract: In a nuclear power plant, a corrosion-resistant oxide film on a surface of the metal component of a reactor structure is exposed to a high-temperature water, the corrosion-resistant oxide film containing an oxide having a property of a P-type semiconductor, and a catalytic substance having a property of an N-type semiconductor is deposited on the oxide film. The oxide film maintains the property of the P-type semiconductor.

Abstract: Example embodiments relate to a method and apparatus for reducing electrostatic deposition of charged particles on wetted surfaces that are exposed, periodically or substantially continuously, to high velocity fluid flow within a coolant flow path in a nuclear reactor. The method may include depositing a first or base dielectric layer and a second or outer dielectric layer on a conductive surface that forms a portion of a high velocity flow path to attain the apparatus. The first dielectric layer material is selected to provide improved adhesion and insulation to the conductive surface and the second dielectric layer material is selected to provide suitable adhesion to the first dielectric layer and improved corrosion and/or mechanical resistance in the anticipated operating environment.

Abstract: Disclosed herein is a fully passive decay heat removal system utilizing a partially immersed heat exchanger, the system comprising: a hot pool; an intermediate heat exchanger which heat-exchanges with the sodium of the hot pool; a cold pool; a support barrel extending vertically through the boundary between the hot pool and the cold pool; a sodium-sodium decay heat exchanger received in the support barrel; a sodium-air heat exchanger provided at a position higher than the sodium-sodium decay heat exchanger; an intermediate sodium loop connecting the sodium-sodium decay heat exchanger with the sodium-air heat exchanger; and a primary pump, wherein a portion of the effective heat transfer tube of the sodium-sodium decay heat exchanger is immersed in the cold pool, particularly in a normal operating state, and the surface of the lower end of a shroud for the sodium-sodium decay heat exchanger, the lower end being immersed in the sodium of the cold pool, has perforated holes.

Abstract: A computer-implemented system and method for managing operations in a nuclear power plant generates an electronic request for a permit to perform work in the plant, performs a risk assessment using a rules engine to determine a level of fire risk posed by the work, automatically determines one or more compensatory measures to provide protection against the level of fire risk posed by work, generates a risk score based the probabilistic assessment, and generates electronic authorization for the permit based on the risk score.

Abstract: The present invention relates to a longitudinally divided emergency core cooling (ECC) duct in order to efficiently inject safety water to core of a pressurized light-water nuclear reactor. The ECC duct includes side supports for preventing the flow-induced vibration in the annular downcomer, and has structural stability while thermally expanding and contracting. A longitudinally divided ECC duct for emergency core cooling water injection of a nuclear reactor is provided on the periphery of a core barrel of a nuclear reactor, includes an emergency core cooling water inlet facing a direct vessel injection nozzle, and extends in a longitudinal direction of the core barrel. The longitudinally divided ECC duct is divided into a plurality of longitudinally-divided ducts in the longitudinal direction of the longitudinally divided ECC duct.

Abstract: Provided is a modular reactor head area assembly. The modular reactor head area assembly is installed on a reactor head, and includes: a seismic support structure that performs functions of lifting, moving and reinstallation of the reactor head and control rod driving apparatuses, cooling of the control rod driving apparatuses, shielding of missile parts, and supporting with respect to a seismic load, and disperses a load applied to the control rod driving apparatuses; an upper module that is an assembly of components located at an upper portion of the seismic support structure for the control rod driving apparatuses; and a lower module that is an assembly of components located at a lower portion of the seismic support structure for the control rod driving apparatuses. The upper module and the lower module are 252 detachably coupled to each other so that maintenance of the control rod driving apparatus can be performed easily.

Abstract: A system includes a containment vessel configured to prohibit a release of a coolant, and a reactor vessel mounted inside the containment vessel. An outer surface of the reactor vessel is exposed to below atmospheric pressure, wherein substantially all gases are evacuated from within the containment vessel.

Abstract: The present invention provides a method of operating a Boiling Water Reactor, having the steps of analyzing LPRM signals for oscilliatory behavior indicative of neutron-flux-coupled density wave oscillations, determining if oscilliatory behavior is present in the signals; initiating a reactor protective corrective action if the oscilliatory behavior is determined, and in addition, initiating corrective actions if neutron uncoupled oscillations are possible. Detecting the later is performed through analytically determined exclusion zone on the power flow map or by on-line stability calculations for several high power channels.

Abstract: Method of repairing nuclear reactors that include one or more submerged lines welded to one or more support brackets may include: removing a damaged section of one of the one or more submerged lines; and replacing the damaged section of the one of the one or more submerged lines without welding. Methods of operating nuclear reactors that include one or more submerged lines welded to one or more support brackets may include: shutting down the nuclear reactor; repairing damage to at least one of the one or more submerged lines without welding; and starting up the nuclear reactor. Methods of operating nuclear reactors that include one or more submerged lines welded to one or more support brackets may include: cooling down the nuclear reactor; repairing damage to at least one of the one or more submerged lines without welding; and heating up the nuclear reactor.