G21C3/048

PELLET HANDLING APPARATUS AND FUEL ROD LOADING METHOD
20200203030 · 2020-06-25 ·

A pellet magazine includes a plurality of pellet bores sized to receive pellets for loading into a fuel rod. A fuel rod loading system includes a plurality of pellet loading stations each designated to load a single pellet type into one or more pellet bores of the pellet magazine, a rod loading station configured to unload pellets from the pellet bores of the pellet magazine into a fuel rod, and a conveyance system configured to transport the pellet magazine to the loading stations and then to the rod loading station in a defined sequence.

High Yield ICF Target for Large Radiation Gains

A target assembly for Inertial Confinement Fusion (ICF) achieving a high yield energy output. This high gain target has a low Z fuel/shell region which is lined with a thin layer of a high Z material on the inner surface and then surrounds a low density hotspot region. Adding a thin high Z liner to the inside of the low Z fuel shell has many advantages. As the shell region compresses and heats the central low density hotspot region, the radiation will be contained, and unable to leave the core. This will lower the ignition temperature of target considerably (around a factor of 4). A high Z shell liner may also increase the burn fraction of the fuel as well as increase the areal density (r) of the hotspot.

THORIUM-BASED FUEL DESIGN FOR PRESSURIZED HEAVY WATER REACTORS
20240021328 · 2024-01-18 ·

Thorium-based fuel bundles are used in existing PHWR reactors (e.g., Indian 220 MWe PHWR, Indian 540 MWe PHWR, Indian 700 MWe PHWR, CANDU 300/600/900) in place of conventional uranium-based fuel bundles, with little or no modifications to the reactor. The fuel composition of such bundles is 60+ wt % thorium, with the balance of fuel provided by low-enriched uranium (LEU), which has been enriched to 13-19.95% .sup.235U. According to various embodiments, the use of such thorium-based fuel bundles provides (1) 100% of the nominal power over the entire life cycle of the core, (2) high burnup, and (3) non-proliferative spent fuel bundles having a total isotopic uranium concentration of less than 12 wt %. Reprocessing of spent fuel bundles is also avoided.

NUCLEAR FUEL PELLET HAVING ENHANCED THERMAL CONDUCTIVITY AND METHOD OF MANUFACTURING THE SAME

Disclosed are a nuclear fuel pellet having enhanced thermal conductivity and a method of manufacturing the same, the method including (a) a step of manufacturing a mixture including a nuclear fuel oxide powder and a thermally conductive plate-shaped metal powder; and (b) a step of molding and then heat-treating the thermally conductive plate-shaped metal powder to have an orientation in a horizontal direction in the mixture, thereby forming a pellet.

Thorium-based fuel design for pressurized heavy water reactors

Thorium-based fuel bundles according to one or more embodiments of the present invention are used in existing PHWR reactors (e.g., Indian 220 MWe PHWR, Indian 540 MWe PHWR, Indian 700 MWe PHWR, CANDU 300/600/900) in place of conventional uranium-based fuel bundles, with little or no modifications to the reactor. The fuel composition of such bundles is 60+ wt % thorium, with the balance of fuel provided by low-enriched uranium (LEU), which has been enriched to 13-19.95% 235U. According to various embodiments, the use of such thorium-based fuel bundles provides (1) 100% of the nominal power over the entire life cycle of the core, (2) high burnup, and (3) non-proliferative spent fuel bundles having a total isotopic uranium concentration of less than 12 wt %. Reprocessing of spent fuel bundles is also avoided.

HIGH ENERGY NUCLEAR FUEL, FUEL ASSEMBLY, AND REFUELING METHOD

Provided herein is a nuclear fuel assembly for a pressurized water reactor. The nuclear fuel assembly comprises: a plurality of nuclear fuel rods configured to contain a fissile material, wherein the nuclear fuel assembly is configured such that a hydrogen to uranium ratio for the fuel assembly, when coolant and the fissile material are present under operating conditions, is at least 4.0. Also provided herein is a method for refueling a pressurized water nuclear reactor comprising a nuclear fuel assembly of the present disclosure.

FUNCTIONALLY GRADED LATTICE CERMET FUEL STRUCTURE WITH SHAPE CORRESPONDING TO A MATHEMATICALLY-BASED PERIODIC SOLID, PARTICULARLY FOR NUCLEAR THERMAL PROPULSION APPLICATIONS

Nuclear propulsion fission reactor structure has an active core region including fuel element structures, a reflector with rotatable neutron absorber structures (such as drum absorbers), and a core former conformal mating the outer surface of the fuel element structures to the reflector. Fuel element structures are arranged abutting nearest neighbor fuel element structures in a tri-pitch design. Cladding bodies defining coolant channels are inserted into and joined to lower and upper core plates to from a continuous structure that is a first portion of the containment structure. The body of the fuel element has a structure with a shape corresponding to a mathematically-based periodic solid, such as a triply periodic minimal surface (TPMS) in a gyroid structure. The nuclear propulsion fission reactor structure can be incorporated into a nuclear thermal propulsion engine for propulsion applications, such as space propulsion.

THORIUM-BASED FUEL DESIGN FOR PRESSURIZED HEAVY WATER REACTORS
20240266079 · 2024-08-08 ·

Thorium-based fuel bundles according to one or more embodiments of the present invention provide a fresh fuel bundle comprising a first ring of fuel pins and a second ring of fuel pins. Each ring fuel pin has a fuel composition comprising uranium and thorium. The first ring fuel pins differ from the second ring fuel pins in each of the thorium wt %, uranium wt %, and .sup.235U enrichment.

ANNULAR NUCLEAR FUEL PELLETS WITH DISCRETE BURNABLE ABSORBER PINS

An annular nuclear fuel pellet in combination with an inserted discrete neutron absorber. The pellet/absorber may be compatible with existing or future nuclear fuel assembly designs. The concept involves the use of nuclear fuel (e.g., uranium dioxide or uranium silicide) formed into annular fuel pellets which can then have a discrete absorber material inserted into the center of the pin. Preferably, the discrete absorber is a non-parasitic absorber. The resulting pellet/absorber can then be stacked into a fuel rod which is arranged in a nuclear fuel assembly. Dimensioning of the annular pellet and absorber and selection of the absorber material and density can allow the concept to be tailored for various nuclear fuel applications.

SPHERICAL FUEL ELEMENT FORMING APPARATUS

A spherical fuel element forming apparatus comprises a fuel area forming system, a fuel-free area shaping system and a green sphere pressing system connected sequentially. The fuel area forming system is used for evenly mixing a core sphere matrix powder with nuclear fuel particles and then pressing the mixed core sphere matrix powder and nuclear fuel particles into core spheres. The fuel-free area shaping system is used for preparing a spherical fuel element from the core spheres covered by a fuel-free matrix powder. The green sphere pressing system is used for pressing the spherical fuel elements into green spheres. The spherical fuel element forming apparatus is distributed according to a technical process flow line operation, and is compact in structure and convenient to operate. Sphere greens after being finally pressed are high in sphericity, fuel element cost is lowered, and the finished product rate is high.