An enhanced architecture for a nuclear reactor core includes several technologies: (1) nuclear fuel tiles (S-Block); and (2) a high-temperature thermal insulator and tube liners with a low-temperature solid-phase moderator (U-Mod) to improve safety, reliability, heat transfer, efficiency, and compactness. In S-Block, nuclear fuel tiles include a fuel shape designed with an interlocking geometry pattern to optimize heat transfer between nuclear fuel tiles and into a fuel coolant and bring the fuel coolant in direct contact with the nuclear fuel tiles. Nuclear fuel tiles can be shaped with discontinuous nuclear fuel lateral facets and have fuel coolant passages formed therein to provide direct contact between the fuel coolant and the nuclear fuel tiles. In U-Mod, tube liners with low hydrogen diffusivity retain hydrogen in the low-temperature solid-phase moderator even at elevated temperatures and the high-temperature thermal insulator insulates the solid-phase moderator from the nuclear fuel tiles.

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.

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.

Passive reactivity control technologies that enable reactivity control of a nuclear thermal propulsion (NTP) system with little to no active mechanical movement of circumferential control drums. By minimizing or eliminating the need for mechanical movement of the circumferential control drums during an NTP burn, the reactivity control technologies simplify controlling an NTP reactor and increase the overall performance of the NTP system. The reactivity control technologies mitigate and counteract the effects of xenon, the dominant fission product contributing to reactivity transients. Examples of reactivity control technologies include, employing burnable neutron poisons, tuning hydrogen pressure, adjusting wait time between burn cycles or merging burn cycles, and enhancement of temperature feedback mechanisms. The reactivity control technologies are applicable to low-enriched uranium NTP systems, including graphite composite fueled and tungsten ceramic and metal matrix (CERMET), or any moderated NTP system, such as highly-enriched uranium graphite composite NTP systems.

Passive reactivity control technologies that enable reactivity control of a nuclear thermal propulsion (NTP) system with little to no active mechanical movement of circumferential control drums. By minimizing or eliminating the need for mechanical movement of the circumferential control drums during an NTP burn, the reactivity control technologies simplify controlling an NTP reactor and increase the overall performance of the NTP system. The reactivity control technologies mitigate and counteract the effects of xenon, the dominant fission product contributing to reactivity transients. Examples of reactivity control technologies include, employing burnable neutron poisons, tuning hydrogen pressure, adjusting wait time between burn cycles or merging burn cycles, and enhancement of temperature feedback mechanisms. The reactivity control technologies are applicable to low-enriched uranium NTP systems, including graphite composite fueled and tungsten ceramic and metal matrix (CERMET), or any moderated NTP system, such as highly-enriched uranium graphite composite NTP systems.

A control drum system for a nuclear reactor including a reactor core, including an ex-core reflector including a plurality of cylindrical apertures, a plurality of control drum assemblies, each control drum assembly including a drive shaft, a drum cylinder affixed to a bottom end of the drive shaft, and a planetary gear attached to a top end of the drive shaft, wherein each drum cylinder is rotatably received in a cylindrical aperture, a first control drum drive motor operably connected to a first control drum assembly, and an annular ring gear that is operably connected to the planetary gear of each of the control drum assemblies so that all the control drum assemblies rotate simultaneously.

A radioactive power generation system is disclosed, the system comprising a radioactive power generator and a releasable antiproton containment. The radioactive power generator includes a radioisotope material. The releasable antiproton containment comprising a plurality of antiprotons contained in isolation from the radioisotope material. The releasable antiproton containment is configured to selectively release the antiprotons from the releasable antiproton containment such that the antiprotons can annihilate the radioisotope material in a fission event to reenergize the radioactive power generator.

Provided herein is a neutron moderation module and a thermal-neutron nuclear micro-reactor.

Provided herein is a neutron moderation module and a thermal-neutron nuclear micro-reactor.

An exemplary embodiment can include an apparatus including: an internal-external hybrid nuclear reactor, which can include: at least one reciprocating internal engine; and at least one external reactor integrated with said at least one reciprocating internal engine. The reciprocating engine can receive nanofuel (including moderator, nanoscale molecular dimensions & molecular mixture) internally in an internal combustion engine that releases nuclear energy. A method of operating the hybrid nuclear reactor can include operating the reciprocating internal engine loaded with nanofuel in spark or compression ignition mode. A method of cycling the reciprocating internal engine, can include compressing nanofuel; igniting nanofuel; capturing energy released in nanofuel, which is also the working fluid; and using the working fluid to perform mechanical work or generate heat.