FRAMATOME

A method for simulating an ultrasonic response of a metal part is carried out by an electronic simulating device. The method includes computing a first distribution of ultrasonic waves for the part without defect, in response to an ultrasonic excitation toward said part computing a second distribution of ultrasonic waves for a predefined zone (S 3 k ) of the part, including a defect ( 20 ), in response to an ultrasonic excitation toward said zone (S 3 k ), with the computation of elementary distributions, each corresponding to an ultrasonic response received by a receiver located at a border (F) of said zone; and determining a resultant distribution of ultrasonic waves for the part with defect, from the first and second computed distributions, the resultant distribution forming a simulation of an ultrasonic response received from the part including the defect ( 20 ), in response to an ultrasonic excitation toward said part.

A method for calculating a PCI margin associated with a loading pattern of a nuclear reactor including a core into which fuel assemblies are loaded according to the loading pattern is implemented by an electronic system. The fuel assemblies include fuel rods each including fuel pellets of nuclear fuel and a cladding surrounding the pellets. This method includes calculating ( 100 ) a reference principal PCI margin for a reference loading pattern of the fuel assemblies in the core; calculating ( 110 ) a reference secondary PCI margin for the reference pattern; calculating ( 120 ) a modified secondary PCI margin for a modified loading pattern of the fuel assemblies in the core, and calculating ( 130 ) a modified principal PCI margin for the modified pattern, depending on a comparison of the modified secondary PCI margin with the reference secondary PCI margin.

A tubular component for a pressurised-water nuclear reactor, has the following composition by weight: 0.8%≤Nb≤2.8%; traces≤Sn≤0.65%; 0.015%≤Fe≤0.40%; preferably 0.020%≤Fe≤0.35%; traces≤C≤100 ppm; 600 ppm≤O≤2300 ppm; preferably 900 ppm≤O≤1800 ppm; 5 ppm≤S≤100 ppm; preferably 8 ppm≤S≤35 ppm; traces≤Cr+V+Mo+Cu≤0.35%; traces≤Hf≤100 ppm; F≤1 ppm; the remainder being zirconium and impurities resulting from production. The tubular component has an outer surface with a roughness Ra less than or equal to 0.5 μm, obtained following a final mechanical polishing step. The outer surface has a roughness Rsk≤1 in absolute value and a roughness Rku≤10.

A boring assembly extends along a main axis and comprises a boring head comprising at least one first nozzle and at least one second nozzle The or each second nozzle is different from the or each first nozzle. The boring assembly includes a first delivery device configured to deliver a jet of abrasive-free water at a pressure comprised between 2000 bar and 4000 bar to the at least one first nozzle. The boring assembly includes a second delivery device configured to deliver a jet containing at least one abrasive material at a pressure comprised between 2000 bar and 6000 bar to the at least one second nozzle.

A leakage testing device for testing leakage of a nuclear fuel assembly ( 18 ) by sipping. The device includes a collection assembly ( 32 ) that is configured to close an upper end ( 24 A) of a cell ( 24 ) of a storage rack ( 22 ) for storing nuclear fuel assemblies discharged from a nuclear reactor ( 4 ). The closing prevents water contained in the cell from escaping via the upper end of the cell. The collection assembly is configured to collect products containing possible fission products released by a nuclear fuel assembly contained in the cell.

A method for calculating a PCI margin associated with a loading pattern of a nuclear reactor including a core into which fuel assemblies are loaded according to the loading pattern is implemented by an electronic system. The fuel assemblies include fuel rods each including fuel pellets of nuclear fuel and a cladding surrounding the pellets. This method includes calculating a reference principal PCI margin for a reference loading pattern of the fuel assemblies in the core; calculating a reference secondary PCI margin for the reference pattern; calculating a modified secondary PCI margin for a modified loading pattern of the fuel assemblies in the core, and calculating a modified principal PCI margin for the modified pattern, depending on a comparison of the modified secondary PCI margin with the reference secondary PCI margin.

A system ( 1 ) includes a module ( 30 ) for calculating a design of experiment comprising a plurality of software tasks to be performed in order to solve a predetermined physical problem. The software tasks of the design of experiment have a first priority level. The system also includes a module ( 4 ) for scheduling the execution of software tasks by the computing system, configured to check for the presence of at least one software task with a second priority level higher than the first priority level waiting to be executed; in case of the presence of at least one such software task, obtaining freed-up computational resources for executing said at least one software task of a second priority level; in the absence of at least one such software task, allocate at least some of the software tasks of the first priority level to the available computational resources.

The method comprises the following steps: acquisition of a plurality of quantities characterizing the operation of the nuclear reactor; calculation of at least one critical thermal flux ratio using a deep neural network, the entries of the deep neural network being determined by using the acquired quantities, the deep neural network comprising at least two hidden layers of at least five neurons each; calculation of the deviations between the at least one calculated critical thermal flux ratio and a plurality of predetermined reference threshold values; formulation of a control signal for a reactor control system by using the calculated deviations, the control signal being: automatic reactor shutdown or alarm; do nothing; emergency shutdown of the nuclear reactor or emission of an alarm signal if relevant.

A detector ( 10 ) for high-energy radiography includes, in the following order: a metal screen ( 12 ) arranged to receive incident radiation, at least part of the incident radiation being transmitted through the metal screen and forming a transmitted radiation, a scintillator component ( 14 ) arranged to convert the radiation transmitted by the metal screen into light, and a detection layer ( 16 ) arranged to detect the intensity of the light emitted by the scintillator component. The screen ( 12 ) is made of a metal having an atomic number that is strictly greater than 70 or is made of an alloy comprising at least 50% mass content of one or more metals having an atomic number that is strictly greater than 70 and in that the thickness of the screen is between 20 μm and 900 μm.

A method regulates operating parameters comprising at least the mean temperature of the core (T m ), and the axial power (AO) imbalance.The method includes development of a vector (Us) of control values of the nuclear reactor by a supervisor ( 31 ) implementing a predictive control algorithm; development of a vector (u K ) of corrective values of the nuclear reactor controls by a regulator ( 33 ) implementing a sequenced gain control algorithm; development of a vector (U) of corrected values of the commands of the nuclear reactor, by using the vector (U S ) of the values of the commands produced by the supervisor ( 31 ) and the vector (U K ) of the corrective values of the commands produced by the regulator ( 33 ); and regulation of the operating parameters of the nuclear reactor, by controlling actuators using the vector (U) of the corrected values of the controls.