The present disclosure relates to reducing losses in the effective delayed neutron fraction during the operation of a reactor, making it possible to provide for a high efficiency of burning out of minor actinides, and also that of increasing the leak-tight integrity of the primary circuit and the reliability of the reactor. The above-mentioned technical result is achieved in an integral molten salt fast reactor with a circulating fuel composition, comprising a vessel with inlet and outlet secondary circuit pipelines and a connection pipe for initial filling and replenishment with molten salt coolant, heat exchangers of the primary/secondary circuit, a side reflector, an upper reflector and a lower reflector, a core with a shell, and a main circulation pipe, wherein the side reflector is made of sections between which the heat exchangers of the primary/secondary circuit are arranged such that they lie flush against the shell of the core.

The present disclosure relates to reducing losses in the effective delayed neutron fraction during the operation of a reactor, making it possible to provide for a high efficiency of burning out of minor actinides, and also that of increasing the leak-tight integrity of the primary circuit and the reliability of the reactor. The above-mentioned technical result is achieved in an integral molten salt fast reactor with a circulating fuel composition, comprising a vessel with inlet and outlet secondary circuit pipelines and a connection pipe for initial filling and replenishment with molten salt coolant, heat exchangers of the primary/secondary circuit, a side reflector, an upper reflector and a lower reflector, a core with a shell, and a main circulation pipe, wherein the side reflector is made of sections between which the heat exchangers of the primary/secondary circuit are arranged such that they lie flush against the shell of the core.

Ensuring a high output temperature while preventing leakage of radioactive substances, etc. A nuclear reactor includes a fuel unit; a shield unit that covers a circumference of the fuel unit for shielding from radioactive rays; and a heat conductive portion that penetrates the shield unit, is arranged such that the heat conductive portion extends to inside of the fuel unit and outside of the shield unit, and transfers heat of the fuel unit to the outside of the shield unit by solid heat conduction.

Disclosed herein is a reactor including a reactor vessel and a containment vessel configured to surround the reactor vessel. The containment vessel includes a thermal radiation shield disposed on an inner wall, and a gap between the reactor vessel and the containment vessel is in an atmospheric pressure and air atmosphere state.

A system for transferring heat from a nuclear reactor comprises a nuclear reactor comprising a nuclear fuel and a reactor vessel surrounding the nuclear reactor and a heat transfer system surrounding the nuclear reactor. The heat transfer system comprises an inner wall surrounding the nuclear reactor vessel, first fins coupled to an outer surface of inner wall, an outer wall between the inner wall and a surrounding environment, and second fins coupled to an inner surface of the outer wall and extending in a volume between the outer surface of the inner wall and the inner surface of the outer wall, the outer surface of the inner wall and the first fins configured to transfer heat from the nuclear reactor core to the second fins and the inner surface of the outer wall by thermal radiation. The heat transfer system may be directly coupled to the nuclear reactor vessel, or may be coupled to an external reflector surrounding the nuclear reactor vessel. Related heat transfer systems and systems for selectively removing heat from a nuclear reactor are disclosed.

A system for transferring heat from a nuclear reactor comprises a nuclear reactor comprising a nuclear fuel and a reactor vessel surrounding the nuclear reactor and a heat transfer system surrounding the nuclear reactor. The heat transfer system comprises an inner wall surrounding the nuclear reactor vessel, first fins coupled to an outer surface of inner wall, an outer wall between the inner wall and a surrounding environment, and second fins coupled to an inner surface of the outer wall and extending in a volume between the outer surface of the inner wall and the inner surface of the outer wall, the outer surface of the inner wall and the first fins configured to transfer heat from the nuclear reactor core to the second fins and the inner surface of the outer wall by thermal radiation. The heat transfer system may be directly coupled to the nuclear reactor vessel, or may be coupled to an external reflector surrounding the nuclear reactor vessel. Related heat transfer systems and systems for selectively removing heat from a nuclear reactor are disclosed.

A fuel core for a nuclear reactor in one embodiment includes an upper internals unit and a lower internals unit comprising nuclear fuel assemblies. The assembled fuel core includes an upper core plate, a lower core plate, and a plurality of channel boxes extending therebetween. Each channel box comprises a plurality of outer walls and inner walls collectively defining a longitudinally-extending interior channels or cells having a transverse cross sectional area configured for holding no more than a single nuclear fuel assembly in some embodiments. A cylindrical reflector circumferentially surrounds channel boxes and is engaged at opposing ends by the upper and lower core plates. Adjacent cells within each channel box are formed on opposite sides of inner walls such that the cells are separated from each other by the inner walls alone without any water gaps therebetween which benefits neutronics for some small modular reactor designs.

A fuel core for a nuclear reactor in one embodiment includes an upper internals unit and a lower internals unit comprising nuclear fuel assemblies. The assembled fuel core includes an upper core plate, a lower core plate, and a plurality of channel boxes extending therebetween. Each channel box comprises a plurality of outer walls and inner walls collectively defining a longitudinally-extending interior channels or cells having a transverse cross sectional area configured for holding no more than a single nuclear fuel assembly in some embodiments. A cylindrical reflector circumferentially surrounds channel boxes and is engaged at opposing ends by the upper and lower core plates. Adjacent cells within each channel box are formed on opposite sides of inner walls such that the cells are separated from each other by the inner walls alone without any water gaps therebetween which benefits neutronics for some small modular reactor designs.

A nuclear power generation system includes a nuclear reactor that includes a reactor core fuel and a nuclear reactor vessel, the nuclear reactor vessel covering a surrounding of the reactor core fuel, shielding a space in which the reactor core fuel is present, and shielding radioactive rays; a heat conductive portion that is disposed in at least a part of the nuclear reactor vessel to transfer heat inside the nuclear reactor vessel to an outside by solid heat conduction; a heat exchanger that performs heat exchange between the heat conductive portion and a refrigerant; a refrigerant circulation unit that circulates the refrigerant passing through the heat exchanger; a turbine that is rotated by the refrigerant circulated by the refrigerant circulation unit; and a generator that rotates integrally with the turbine.

A nuclear power generation system includes a nuclear reactor that includes a reactor core fuel and a nuclear reactor vessel, the nuclear reactor vessel covering a surrounding of the reactor core fuel, shielding a space in which the reactor core fuel is present, and shielding radioactive rays; a heat conductive portion that is disposed in at least a part of the nuclear reactor vessel to transfer heat inside the nuclear reactor vessel to an outside by solid heat conduction; a heat exchanger that performs heat exchange between the heat conductive portion and a refrigerant; a refrigerant circulation unit that circulates the refrigerant passing through the heat exchanger; a turbine that is rotated by the refrigerant circulated by the refrigerant circulation unit; and a generator that rotates integrally with the turbine.