A laser wake-field acceleration (LWFA)-based nuclear fission system and related techniques are disclosed. In accordance with some embodiments, the disclosed system may be configured to accelerate charged particles, such as protons, to velocities close to the speed of light utilizing LWFA. The system also may be configured, in accordance with some embodiments, to use these high-energy relativistic charged particles in causing nuclear fission of a given downstream fissionable target, thereby releasing large amounts of harvestable energy. Optionally, the system further may be configured, in accordance with some embodiments, to utilize charged particles resulting from the fission in producing electrical energy.

Illustrative embodiments provide modular nuclear fission deflagration wave reactors and methods for their operation. Illustrative embodiments and aspects include, without limitation, modular nuclear fission deflagration wave reactors, modular nuclear fission deflagration wave reactor modules, methods of operating a modular nuclear fission deflagration wave reactor, and the like.

Provided are a plurality of embodiments, including, but not limited to, a device for generating efficient low and high average power output Gamma Rays via relativistic particle bombardment of element targets using an efficient particle injector and accelerator at low and high average power levels suitable for element transmutation and power generation with an option for efficient remediation of radioisotope release into any environment. The devices utilize diamond or diamond-like carbon materials and active cooling for improved performance.

Provided are a plurality of embodiments, including, but not limited to, a device for generating efficient low and high average power output Gamma Rays via relativistic particle bombardment of element targets using an efficient particle injector and accelerator at low and high average power levels suitable for element transmutation and power generation with an option for efficient remediation of radioisotope release into any environment. The devices utilize diamond or diamond-like carbon materials and active cooling for improved performance.

A nuclear fission reactor fuel assembly adapted to permit expansion of the nuclear fuel contained therein. The fuel assembly comprises an enclosure having enclosure walls to sealingly enclose a nuclear fuel foam defining a plurality of interconnected open-cell voids or a plurality of closed-cell voids. The voids permit expansion of the foam toward the voids, which expansion may be due to heat generation and/or fission gas release. The voids shrink or reduce in volume as the foam expands. Pressure on the enclosure walls is substantially reduced because the foam expands toward and even into the voids rather than against the enclosure walls. Thus, the voids provide space into which the foam can expand.

Illustrative embodiments provide a nuclear fission reactor, that includes a reactor vessel, a nuclear fission fuel element capable of generating a gaseous fission product, a valve body defining a plenum for receiving the gaseous fission product, and a valve in operative communication with the plenum for controllably venting the gaseous fission product from the plenum.

Disclosed embodiments include nuclear fission reactors, nuclear fission fuel pins, methods of operating a nuclear fission reactor, methods of fueling a nuclear fission reactor, and methods of fabricating a nuclear fission fuel pin.

Disclosed embodiments include nuclear fission reactors, nuclear fission fuel pins, methods of operating a nuclear fission reactor, methods of fueling a nuclear fission reactor, and methods of fabricating a nuclear fission fuel pin.

The fuel element of the present invention includes a cladding tube and a metal fuel contained in the cladding tube, in which a gas plenum region is formed above the metal fuel and inside the cladding tube and has a small-diameter portion in the gas plenum region. Further, the fuel assembly of the present invention includes the fuel element of the present invention and a wrapper tube surrounding the fuel element, in which a coolant material passage is formed between the fuel element and the fuel element. Further, the core of the present invention includes an inner core fuel region loaded with the fuel assembly according to the present invention, and an outer core fuel region loaded with the fuel assembly of the present invention.

An experimental system a method for studying jet impact characteristics at a core outlet of a fast reactor are provided. The system includes a jet impact main loop including a water storage tank, plunger pumps, a filter, preheaters, a jet impact chamber, a heat regenerator, a condenser, valves, flow meters and pipelines connecting these facilities; a cooling loop including cooling tower, a cooling pump, a regulating valve and a flow meter; and a makeup water loop including a deionized water machine, a makeup water tank and a plunger pump. Water in the water storage tank flows to the heat regenerator via the plunger pump, is preliminarily heated by the heat regenerator and then is divided into three branches to flow to the jet impact container.