THERMAL POWER REACTOR

Abstract

A thermal power reactor (100) includes a reactor core (102) that generates thermal energy and a solid state thermal conductor (106) extending into and thermally integrated with the reactor core (102). The solid state thermal conductor (106) transfers thermal energy generated by the reactor core (102) away from the reactor core (102).

Claims

1. A thermal power reactor comprising: a reactor core arranged to generate thermal energy; and a solid state thermal conductor extending into and thermally integrated with the reactor core, wherein the solid state thermal conductor is arranged to transfer thermal energy generated by the reactor core away from the reactor core.

2. The thermal power reactor as claimed in claim 1, wherein the solid state thermal conductor comprises an internal portion extending into the thermal reactor core and an external portion extending away from the reactor core.

3. The thermal power reactor as claimed in claim 2, wherein the internal portion and the external portion of the solid state thermal conductor are thermally connected to each other.

4. The thermal power reactor as claimed in claim 2, wherein the internal portion and the external portion are formed from different materials.

5. The thermal power reactor as claimed in claim 2, wherein the internal portion of the solid state thermal conductor comprises a mesh extending within the reactor core.

6. The thermal power reactor as claimed in claim 2, wherein the internal portion of the solid state thermal conductor comprises a plurality of layers.

7. The thermal power reactor as claimed in claim 6, further comprising a plurality of fuels discs positioned between the plurality of layers of the solid state thermal conductor.

8. The thermal power reactor as claimed in claim 2, wherein the internal solid state thermal conductor comprises graphite and/or a metal alloy.

9. The thermal power reactor as claimed in claim 2, wherein the external portion of the solid state thermal conductor comprises a plurality of layers of graphene.

10. The thermal power reactor as claimed in claim 9, wherein the external portion of the solid state thermal conductor comprises one or more intermediate separating layers that interleave the plurality of layers of graphene.

11. The thermal power reactor as claimed in claim 10, wherein the one or more intermediate separating layers comprise copper.

12. (canceled)

13. The thermal power reactor as claimed in claim 1, wherein the thermal power reactor comprises a heat conversion unit for converting thermal energy to electricity which is thermally connected to the reactor core via the solid state thermal conductor.

14. (canceled)

15. The thermal power reactor as claimed in claim 13, wherein the heat conversion unit comprises a solid state heat conversion unit.

16. The thermal power reactor as claimed in claim 13, wherein the heat conversion unit comprises a Stirling engine.

17. The thermal reactor as claimed in claim 16, wherein an external portion of the solid state thermal conductor extends into the Stirling engine, or wherein an external portion of the solid state thermal conductor is arranged to transfer thermal energy to a working fluid of the Stirling engine.

18. The thermal reactor as claimed in claim 16, wherein the external portion of the solid state thermal conductor comprises graphene, wherein the graphene is wrapped around the Stirling engine.

19. The thermal reactor as claimed in claim 16, wherein the Stirling engine is remote from the reactor core.

20. (canceled)

21. The thermal power reactor as claimed in claim 1, wherein the thermal power reactor comprises a shield encasing the reactor core and the heat conversion unit comprises a solid state heat conversion unit and the solid state heat conversion unit is located at the shield of the reactor core.

22. The thermal power reactor as claimed in claim 1, wherein the thermal power reactor comprises a shield encasing the reactor core and the solid state thermal conductor extends through the shield.

23. The thermal power reactor as claimed in claim 22, wherein the solid state thermal conductor comprises a non-linear portion that extends through the shield wherein the non-linear portion comprises an S-shaped, a U-shaped or a labyrinthine path.

24. (canceled)

25. (canceled)

Description

[0043] Certain embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings in which:

[0044] FIG. 1 shows schematically a thermal power reactor according to an embodiment of the present invention;

[0045] FIGS. 2 and 3 show cross-sections of a reactor core for use with a thermal power reactor according to an embodiment of the present invention;

[0046] FIG. 4 shows a cross-section through the wall of a reactor core for use with a thermal power reactor according to an embodiment of the present invention; and

[0047] FIG. 5 shows schematically a reactor core for use with a thermal power reactor according to an embodiment of the present invention.

[0048] Various embodiments of a thermal power reactor will now be described. The thermal power reactors shown may be suitable for use in space, e.g. to act as a power source for a spacecraft or space probe, or on a surface landing mission.

[0049] FIG. 1 shows schematically a thermal power reactor 100 in accordance with an embodiment of the present invention. The thermal power reactor 100 may be a nuclear fusion reactor used for commercial power generation. In such examples, the thermal power reactor 100 may be large scale, capable of producing a commercially beneficial power output. The thermal power reactor 100 may also be a nuclear fusion reactor implemented in a spacecraft or a space probe. In such examples, the thermal power reactor 100 may be a compact, small reactor providing the small amount of power required by the spacecraft. It will also be appreciated by a person skilled in the art that the thermal power reactor 100 may be a nuclear fusion reactor or furnace, e.g. for burning coal.

[0050] The thermal power reactor 100 comprises a reactor core 102. The type of reactor core 102 used corresponds to the type of thermal power reactor 100. For example, when the thermal power reactor 100 is a nuclear fission reactor, the reactor core 102 is a nuclear fission core. The reactor core 102 further comprises a fuel (not shown in FIG. 1) for generating thermal energy. In the example of a nuclear fission reactor, the fuel may contain nuclear isotopes (e.g. uraninum-235, plutonium-239 and/or uranium-238) that are used in fission reactions to generate thermal energy. The fuel may be a mixture of such nuclear isotopes depending on the requirements of the thermal power reactor 100.

[0051] The thermal power reactor 100 further comprises a heat conversion unit 104. The heat conversion unit 104 may, for example, be a thermoelectric generator or a Stirling engine. The heat conversion unit 104 converts thermal energy produced in the reactor core 102 to another form of energy, which may be more suitable for particular applications. For example, the heat conversion unit 100 may convert the thermal energy into kinetic energy (e.g. when the heat conversion unit 100 comprises a Stirling engine). This kinetic energy may be used to drive a turbine to be converted into electrical energy. The heat conversion unit 100 may also convert the thermal energy directly into electrical energy (e.g. when the heat conversion unit 100 comprises a thermoelectric generator).

[0052] In order for thermal energy to be transferred from the reactor core 102 to the heat conversion unit 104, the reactor core 102 and the heat conversion unit 104 must be thermally connected such that thermal energy can flow between them. This thermal connection is provided by the solid state thermal conductor 106 that is arranged between, and in good thermal contact with, the reactor core 102 and the heat conversion unit 104.

[0053] The solid state thermal conductor 106 is formed at least partially from graphene, e.g. in the section extending between the reactor core 102 and the heat conversion unit 104. This may be seen in embodiments in which the heat conversion unit is located at some distance from the reactor core. In this section, the solid state thermal conductor 106 comprises multiple layers of graphene ribbons. The multiple layers of graphene ribbons are interleaved by multiple layers of copper separating the layers of graphene and covered in an outer layer of gold foil. When the heat conversion unit 104 comprises a Stirling engine, the layers of graphene are wrapped around the hot end of the Stirling engine to transfer heat generated in the reactor core 102 into the working fluid of the Stirling engine.

[0054] To transfer thermal energy between the reactor core 102 and the heat conversion unit 104, the solid state thermal conductor 106 is in thermal contact with both. In the embodiment shown in FIG. 1, the solid state thermal conductor 106 has an internal portion 108 which extends into the reactor core 102. Exemplary arrangements of the internal portion 108 of the solid state thermal conductor 106 and the reactor core 102 are shown in FIGS. 2, 3 and 5. In the embodiment shown in FIG. 1, the solid state thermal conductor has an external portion 110 which extends into the heat conversion unit 104. Both or one of the portions 108, 110 may be formed from graphene, or may be formed from a high conductivity metal alloy.

[0055] FIG. 2 shows a cross-section of a reactor core for use with a thermal power reactor according to an embodiment of the present invention. FIG. 2 shows an exemplary arrangement of the internal portion 208 of a solid state thermal conductor 206 within a reactor core 202. In the arrangement shown in FIG. 2, the reactor core 202 contains a plurality of (e.g. TRISO packed, prismatic graphite) fuel discs 210. The fission reactions that generate thermal energy occur within the fuel discs 210.

[0056] The internal portion 208 of the solid state thermal conductor 206 comprises multiple sheets, e.g. of graphite or metal (e.g. tungsten-rhenium) alloy. A sheet is placed between each fuel disc 210. The fuel discs 210 are stacked in a manner such as to form a cylinder of discs, with each disc 210 being separated from the adjacent disc 210 in the cylinder by a sheet of the internal portion 208 of the solid state thermal conductor 206. Each sheet conducts thermal energy produced in the fuel discs out of the reactor core 202, and into the remainder of the solid state thermal conductor 206. FIG. 3 shows a different cross-section of the reactor core 202 shown in FIG. 2, showing the solid state thermal conductor 206.

[0057] In both FIGS. 2 and 3, a reflecting shield 212 is shown encasing the fuel discs 210 in the reactor core 202. The shield 212 helps to contain (by reflecting or absorbing) contaminating (e.g. radioactive) materials that are produced by the reactions in the reactor core 202. The shield 212 is manufactured from steel, or formed from a combination of layers of different materials.

[0058] The solid state thermal conductor 206 extends through the shield 212. As shown in FIG. 3, the internal portion 208 of the solid state thermal conductor 206 extends through the shield 212 and is connected to an external portion 216 of the extends through the shield 212 by a thermally conductive coupling 214.

[0059] It will be appreciated that in the embodiment shown in FIGS. 2 and 3, the internal portion 208 of the solid state thermal conductor 206 extending through the shield 212 may form a path through the shield 212 through which contaminating materials can escape the from the reactor core 202. FIG. 4 demonstrates a solution to this problem.

[0060] FIG. 4 shows a cross-section through the wall of a reactor core for use with a thermal power reactor according to an embodiment of the present invention. FIG. 4 shows a section of the reactor core 410 and a reflecting shield 414 surrounding the reactor core 410. The internal portion 408 of the solid state thermal conductor 406 penetrates out from the reactor core 410 and through the shield 414. The section of the solid state thermal conductor 406 passing through the shield 414 comprises an S-bend 416. The bend 416 results in the solid state thermal conductor 406 having a non-linear path through the shield 414. This decreases the risk of harmful contaminants escaping from the reactor core 410 through the shield 414, as there is no linear route through the solid state thermal conductor 406 along which any contaminating materials (e.g. radioactive particles) could pass without interacting with the shield 414 (which may reflect or absorb them).

[0061] FIG. 5 shows schematically a reactor core 502 for use with a thermal power reactor according to another embodiment of the present invention. In this embodiment, the internal portion 508 of the solid state thermal conductor is arranged as a mesh, e.g. formed from graphite or a metal (e.g. tungsten-rhenium) alloy. The fuel 510 of the reactor core 502 (e.g. in the form of a metallic alloy fuel) is moulded around the mesh.

[0062] It will be seen from the above that in at least preferred embodiments a thermal power reactor is provided in which heat is transported away from the reactor core by a solid state thermal conductor, e.g. comprising graphene. This helps to reduce or eliminate the need for a fluid coolant which has the associated risks of moving parts and failure owing to fluid leakage. Thus embodiments of the thermal power reactor may be suitable for use in space.