A method of controlling a plasma in a nuclear fusion reactor. The nuclear fusion reactor comprises sensors and plasma control inputs. An initial control model is provided, relating readings of at least a subset of the sensors to control of the plasma control inputs. A control loop is performed, comprising: operating the plasma control inputs in dependence upon the sensors according to the control model; determining correlations between readings of each of the sensors, and/or between readings of the sensors and states of the plasma control inputs; and adjusting the control model based on the determined correlations.

A method for analyzing a heat exchanger includes a structural model creation step (S1) of creating a structural model of a heat exchanger; a iron-linear model creation step (S4) of creating a iron-linear model in which a non-linear spring element in an out-of-plane direction, in which a load is generated only at me time of contact between a heat transfer tube and an anti-vibration member, is applied to an opposing portion between the heat transfer tube and the anti-vibration member in a structural model, and a load distribution acquisition step (S5) of performing analysis in which a load in the out-of-plane direction is applied to the non-linear model to acquire load distribution of the heat exchanger from a value of the load in each opposing portion.

A method of decommissioning a nuclear facility, including: exposing the plurality of upper penetration holes by removing the plurality of sandboxes; enlarging an upper space of the cavity by cutting an upper portion of the biological shield concrete that is disposed between the plurality of upper penetration holes and between the plurality of upper penetration holes and the cavity; and separating the nuclear reactor pressure vessel from the biological shield concrete.

Steam generators in power plants exchange energy from a primary medium to a secondary medium for energy extraction. Steam generators include one or more primary conduits and one or more secondary conduits. The conduits do not intermix the mediums and may thus discriminate among different fluid sources and destinations. One conduit may boil feedwater while another reheats steam for use in lower and higher-pressure turbines, respectively. Valves and other selectors divert steam and/or water into the steam generator or to other turbines or the environment for load balancing and other operational characteristics. Conduits circulate around an interior perimeter of the steam generator immersed in the primary medium and may have different cross-sections, radii, and internal structures depending on contained. A water conduit may have less flow area and a tighter coil radius. A steam conduit may include a swirler and rivulet stopper to intermix water in any steam flow.

A control assembly for a nuclear reactor includes a first reactivity control assembly having a first neutron modifying material, a second reactivity control assembly having a second neutron modifying material, and at least one drive mechanism coupled to the first neutron modifying material and the second neutron modifying material. The first neutron modifying material and the second neutron modifying material are selectively repositionable relative to a fuel region of the nuclear reactor. The at least one drive mechanism is configured to provide the first neutron modifying material and the second neutron modifying material in different directions through the fuel region thereby shifting a flux distribution within the fuel region away from the second neutron modifying material.

Reactor buildings and vessel systems are disclosed. A nuclear power system includes: a building structure that comprises at least two exterior side walls and two end walls, at least one of the exterior walls angled non-orthogonally relative to a floor of the building structure, the at least two exterior walls and two end walls defining an interior volume of the building structure; one or more nuclear reactor systems mounted at least partially in the interior volume of the building structure; and one or more heat exchanger systems mounted at least partially to at least one of the exterior walls. A nuclear reactor vessel system includes: a nuclear fission reactor; an inner vessel that defines an inner volume sized to at least partially enclose the nuclear fission reactor; and an outer vessel sized to wholly or substantially enclose the inner vessel, the inner vessel being removable from the outer vessel.

A method designs nuclear reactors using design variables and metric variables. A user specifies ranges for the design variables and threshold values for the metric variables and selects design parameter samples. For each sample, the method runs three processes, which compute metric variables for thermal-hydraulics, neutronics, and stress. The method applies a cost function to compute an aggregate residual of the metric variables compared to the threshold values. The method deploys optimization methods, either training a machine learning model using the samples and computed aggregate residuals, or using genetic algorithms, simulated annealing, or differential evolution. When using Bayesian optimization, the method shrinks the range for each design variable according to correlation between the respective design variable and estimated residuals using the machine learning model. These steps are repeated until a sample having a smallest residual is unchanged for multiple iterations. The final model assesses relative importance of each design variable.

A nuclear fuel includes a net neutron-producing material, a neutron-consuming material, and a neutron-moderating material. Upon exposure of the net-producing material, the neutron-moderating material, and the neutron-consuming material to a neutron source, a ratio of the net neutron-producing material to the neutron-consuming material and a ratio of the net neutron-producing material to the neutron moderating material are operable to convert neutrons into charged particles without producing net neutrons.

A method for determining at least one threshold value of at least one operating parameter of a nuclear reactor is implemented by an electronic determination system and includes the steps of determining a first threshold value of a respective operating parameter for an operation of the reactor at a first power; and determining a second threshold value of said parameter for an operation of the reactor at a second power. The operation at the lower power of the first and second powers is an operation continued for a duration of at least 8 hours over a 24-hour sliding window. The method also includes determining a third threshold value of said parameter for an operation of the reactor at a third power between the first power and the second power.

Electric An Electric Power Generation System generates electric power by capturing energy released from transmutation/conversion of one or more chemical element(s) into one or more other element/s, using any one or more elements of the periodic table. The captured energy is converted into electricity in a rector. The system preferably includes a transmutation reactor and an energy capturing system coupled to the reactor that converts captured energy into electricity, and connecting the electric energy to the electric grid or uses it on site power generation. In particular, the energy released in the of transmutation process is directly converted into electric power. Preferably, transmutation products that emerge in the form of charged particles, X-rays and heat, release energy removed from the fusion product ions as they spiral past electrodes of an inverse cyclotron converter.