Nuclear fuel rods and heat pipes in a graphite moderator matrix for a micro-reactor, with the fuel rods having fuel pellets in a BeO sleeve
A reactor unit cell is disclosed including a graphite moderator structure, a heat pipe positioned in the graphite moderator structure, and a fuel assembly positioned in the graphite moderator structure. The fuel assembly comprises at least one fuel rod. Each fuel rod comprises a beryllium-oxide sleeve and nuclear fuel positioned in the beryllium-oxide sleeve.
1. A reactor unit cell, comprising:
a graphite moderator structure;
a heat pipe positioned in the graphite moderator structure; and
a fuel rod positioned in the graphite moderator structure, wherein the fuel rod comprises:
a beryllium-oxide sleeve; and
nuclear fuel positioned in the beryllium-oxide sleeve, wherein the beryllium-oxide sleeve directly surrounds the nuclear fuel such that the beryllium-oxide sleeve provides protection to the nuclear fuel from migrating metal isotopes from the heat pipe.
2. The reactor unit cell of claim 1 , wherein the fuel rod further comprises a plurality of beryllium-oxide pellets positioned in the beryllium-oxide sleeve.
3. The reactor unit cell of claim 2 , wherein the fuel rod further comprises an end cap coupleable with the beryllium-oxide sleeve, and wherein the beryllium-oxide pellets are positioned between the end cap and the nuclear fuel.
4. The reactor unit cell of claim 1 , wherein a radial gap is defined between the nuclear fuel and the beryllium-oxide sleeve.
5. The reactor unit cell of claim 4 , wherein the radial gap comprises helium gas.
6. The reactor unit cell of claim 4 , wherein the radial gap is in the range of 0.007 cm to 0.01 cm.
7. The reactor unit cell of claim 1 , wherein a radial gap is defined between the fuel rod and the graphite moderator structure.
8. The reactor unit cell of claim 7 , wherein the radial gap comprises helium gas.
9. The reactor unit cell of claim 7 , wherein the radial gap is in the range of 0.1 cm to 0.2 cm.
10. The reactor unit cell of claim 1 , wherein the beryllium-oxide sleeve comprises a wall thickness in the range of 0.15 cm to 0.4 cm.
11. The reactor unit cell of claim 1 , wherein the nuclear fuel comprises TRISO fuel.
12. The reactor unit cell of claim 1 , wherein the beryllium-oxide sleeve directly surrounds the nuclear fuel such that the beryllium-oxide sleeve further provides neutron moderation to the nuclear fuel and a reactivity contribution to the nuclear fuel.
13. A reactor unit cell, comprising:
a graphite moderator matrix;
a heat pipe positioned in the graphite moderator matrix; and
a fuel rod positioned in the graphite moderator matrix, wherein the fuel rod comprises a beryllium-oxide sleeve, wherein nuclear fuel is positionable in the beryllium-oxide sleeve, wherein the beryllium-oxide sleeve directly surrounds the nuclear fuel such that the beryllium-oxide sleeve provides protection to the nuclear fuel from migrating metal isotopes from the heat pipe.
14. The reactor unit cell of claim 13 , wherein the fuel rod further comprises a plurality of beryllium-oxide pellets positioned in the beryllium-oxide sleeve.
15. The reactor unit cell of claim 14 , wherein the fuel rod further comprises:
the nuclear fuel; and
an end cap coupleable with the beryllium-oxide sleeve, wherein the beryllium-oxide pellets are positioned between the end cap and the nuclear fuel.
16. The reactor unit cell of claim 13 , further comprising the nuclear fuel, wherein a radial gap is defined between the nuclear fuel and the beryllium-oxide sleeve.
17. The reactor unit cell of claim 16 , wherein the radial gap comprises helium gas.
18. The reactor unit cell of claim 16 , wherein the radial gap is in the range of 0.007 cm to 0.01 cm.
19. The reactor unit cell of claim 13 , wherein a radial gap is defined between the fuel rod and the graphite moderator matrix.
20. The reactor unit cell of claim 19 , wherein the radial gap comprises helium gas.
21. The reactor unit cell of claim 19 , wherein the radial gap is in the range of 0.1 cm to 0.2 cm.
22. The reactor unit cell of claim 13 , wherein the beryllium-oxide sleeve directly surrounds the nuclear fuel such that the beryllium-oxide sleeve further provides neutron moderation to the nuclear fuel and a reactivity contribution to the nuclear fuel.