General Electric Company

Global Nuclear Fuel - Americas, LLC

Global Nuclear Fuel-Japan Co., Ltd.

Russell M Fawcett

Russell Edward Stachowski

Lukas Trosman

David Grey Smith

William Earl Russell, Ii

Michael T Kiernan

Russell Patrick Higgins

Robert Bryant James

Steven Bruce Shelton

Randy Peter Gonzales

Larry E Fennern

Roy C Challberg

Robert B Elkins

Steven P Congdon

Cary L Kunz

David Joseph Kropaczek

Charles W Dillmann

Michael Scott DeFilippis

Christian Carlos Oyarzun

Steven Barry Sutton

Carlton Wayne Clark

Harold E Townsend

Anthony P Reese

William Charles Cline

Irvin R Kobsa

Gerald Anthony Luciano

Roland Otto Jackson

John Frederick Schardt

Glen Alan Watford

Richard Carl Longren

Richard A Ose

Steven A Hucik

Robert A Rand

Daisuke Goto

Sten O Akerlund

Peter J Savoia

Shingo Fujimaki

Nilkanth T Patel

Russell E Stachowski

A nuclear reactor fuel bundle assembly including: a fuel bundle including an array of fuel rods and water rods mounted in an upper tie plate and housed in walls of a channel, and a pore type debris shield mounted at least partially in the channel, above or below the upper tie plate, the shield extending to or over the walls of the channel, whereby deflecting and/or capturing falling debris from entering the fuel assembly, wherein the shield is design to be durable, yet flexible, and porous.

Debris shield upper tie plate for nuclear fuel assembly and method to shield assembly from debris

In a method of producing isotopes in a light water power reactor, one or more targets within the reactor may be irradiated under a neutron flux to produce one or more isotopes. The targets may be assembled into one or more fuel bundles that are to be loaded in a core of the reactor at a given outage. Power operations in the reactor irradiate the fuel bundles so as to generate desired isotopes, such as one or more radioisotopes at a desired specific activity or stable isotopes at a desired concentration.

Method of producing isotopes in power nuclear reactors

A rod assembly for a fuel bundle of a nuclear reactor may include an upper end piece, lower end piece and a plurality of rod segments attached between the upper and lower end pieces and to each other so as to form an axial length of the rod assembly. The rod assembly may include an adaptor subassembly provided at given connection points for connecting adjacent rod segments or a given rod segment with one of the upper and lower end pieces. The connection points along the axial length of the rod assembly may be located where the rod assembly contacts a spacer in the fuel bundle. One (or more) of the rod segments may include an irradiation target therein for producing a desired isotope when a fuel bundle containing one (or more) rod assemblies is irradiated in a core of the reactor.

Rod assembly for nuclear reactors

A reactor fuel bundle includes both full-length fuel rods and part-length fuel rods. The part-length rods are clumped in two groups&#x2014;a first rod group surrounds one or more water passages which are generally centrally disposed in a channel of the fuel bundle, and a second rod group is distributed about an inner perimeter wall of the channel.

Distributed clumping of part-length rods for a reactor fuel bundle

In a method of determining an operating margin to a given operating limit in a nuclear reactor, operational plant data from an on-line nuclear reactor plant is accessed, and reactor operation is simulated off-line using the operational plant data to generate predicted dependent variable data representative of the given operating limit. The predicted dependent variable data is normalized for evaluation with normalized historical dependent variable data from stored operating cycles of plants having a similar plant configuration to the on-line plant. A time-dependent average bias and a time-dependent uncertainty value for the predicted dependent variable data are determined using the normalized historical dependent variable data, and a risk-tolerance level for the on-line plant is obtained. An operating margin to the given operating limit is determined based on the determined time time-dependent average bias value and time-dependent uncertainty value so as to satisfy the risk-tolerance level of the evaluated plant.

Method of determining margins to operating limits for nuclear reactor operation

In an embodiment of the present invention, the core of a nuclear reactor includes a plurality of fuel cells and a plurality of large control rods. Each large control rod is about two times the width of a conventional control rod and includes four control rod blades extending radially from a central portion and arranged at right angles to each other. The blades define four fuel bundle receiving channels. The core is configured so that the control rods are-arranged in a plurality of staggered rows with four fuel bundles in each receiving channel.

Core configuration for a nuclear reactor

A nuclear fuel bundle has differential peak power limits for the edge or peripheral fuel rods and the interior fuel rods. Also, the magnitude of nuclear fuel in the edge or peripheral rods is decreased in comparison with the magnitude of nuclear fuel in the interior rods. The nuclear reactor can thus operate at higher power output by decreasing the margins between the power outputs and peak power limit of the interior rods, as well as by decreasing the margins between the power outputs of the edge or peripheral rods and the increased peak power limit of those rods. The outer or peripheral edge rods can also be enriched for enhanced power output.

Nuclear fuel bundle having different peak power limits

Fuel bundle and control rod assemblies for a nuclear reactor are described. In one embodiment of the apparatus, the nuclear reactor includes several conventional size fuel bundles and at least one large control rod. The large control rod includes four fuel bundle receiving channels, and each such channel is sized to receive four conventional size fuel bundles.

Fuel bundle and control rod assembly for a nuclear reactor

A boiling water reactor includes a pressure vessel containing a reactor core, chimney, steam separator assembly, and steam dryer assembly therein, with the vessel being filled with reactor water to a normal water level through the steam separator assembly. A plurality of control rod drives extend downwardly from the bottom of the pressure vessel and are operatively joined to control rods extending downwardly into the reactor core. The chimney includes a plurality of channels disposed above the core and laterally spaced apart to define guide slots for receiving the control rods as they are selectively translated upwardly out of the core by the control rod drives. The chimney has a vertical height for increasing the normal water level above the reactor core and for providing a space for the control rods withdrawn from the reactor core by the bottom-mounted control rod drives. The control rods are selectively withdrawn upwardly from the core and inserted downwardly into the core by the control rod drives, which also are effective for selectively releasing the control rods for allowing gravity to insert the control rods into the core.

Boiling water reactor including split control rod drives

A reactor core removable fuel assembly includes upper and lower tie plates having pluralities of fuel rods and hollow control rods extending therebetween. The lower tie plate includes a lower manifold therein joined in flow communication with a reservoir containing a neutron absorbing control liquid, with the reservoir being removable from the reactor core together with the fuel assembly. The control liquid is selectively pumped from the reservoir through the lower manifold and into the control rods for selectively varying the level of the control liquid therein for controlling reactivity.

Reactivity controlled fuel assembly

Fresh fuel bundles are inserted into core locations with small coolant flow orifices, while mid-life fuel bundles are inserted into core locatiosn with large coolant flow locations. Thus, fissile fuel production is promoted at the expense of fissioning early in a bundle lifetime, increasing the effective quantity of fuel available for energy production. Moreover, fissioning is promoted at the expense of conversion later in the bundle lifetime to enhance reactivity of the remaining fissile material and to minimize the further production of fissile fuel. The net result is longer fuel lifetimes and reduced radioactive waste.

Seed and blanket fuel arrangement for dual-phase nuclear reactors

Fuel assemblies of a boiling-water nuclear reactor are inverted during refueling methods. Assemblies burned in a first orientation are subjected to greater burnup near their bottoms and greater conversion of fertile fuel to fissile fuel near their tops. Inverting the assemblies promotes burnup of the actinide products from the conversion of the last cycle. Thus, the procedure greater energy production efficiency and reduced actinide radioactive waste are achieved. One inverted fuel assemblies can be removed for disposal. Alternatively, they can be reinverted to burnup actinide fissile fuel generated at the bottom (while it was downstream of the top) during the second operating cycle. Further inversions are provided for, but the major gains occur during the first and second inversions.

Fuel-assembly inversion for dual-phase nuclear reactors

Growing community of inventors

San Jose, CA, United States of America

Russell M Fawcett