Patent Number: 
Section: claims

1. A nuclear fission reactor fuel assembly configured for controlled removal of a volatile fission product released by a burn wave in a traveling wave nuclear fission reactor, comprising:a porous nuclear fuel body having a volatile fission product therein;an enclosure enclosing the porous nuclear fuel body therein;a fluid control subassembly coupled to the enclosure to control removal of at least a portion of the volatile fission product from the porous nuclear fuel body; anda control unit coupled to the fluid control subassembly to control operation of the fluid control subassembly to controllably release the volatile fission product in response to a selected parameter in the traveling wave nuclear fission reactor. 2. The nuclear fission reactor fuel assembly according to claim 1, wherein the selected parameter includes a power level in the traveling wave nuclear fission reactor. 3. The nuclear fission reactor fuel assembly according to claim 1, wherein the selected parameter includes a neutron population level in the traveling wave nuclear fission reactor. 4. The nuclear fission reactor fuel assembly according to claim 1, wherein the selected parameter includes a volatile fission product pressure level in the traveling wave nuclear fission reactor. 5. The nuclear fission reactor fuel assembly according to claim 1, wherein said the control unit is adapted to permit a controlled release of the volatile fission product in response to a time schedule associated with the traveling wave nuclear fission reactor. 6. The nuclear fission reactor fuel assembly according to claim 1, wherein the control unit is adapted to permit a controlled release of the volatile fission product in response to an amount of time the traveling wave nuclear fission reactor is operated. 7. The nuclear fission reactor fuel assembly according to claim 1, wherein the fluid control subassembly is adapted to permit a controlled release of the volatile fission product in response to a position of the burn wave in the traveling wave nuclear fission reactor. 8. The nuclear fission reactor fuel assembly according to claim 1, wherein a fissile material forms the porous nuclear fuel body. 9. The nuclear fission reactor fuel assembly according to claim 1, wherein a fertile material forms the porous nuclear fuel body. 10. The nuclear fission reactor fuel assembly according to claim 1, wherein a mixture of fissile and fertile material forms the porous nuclear fuel body. 11. The nuclear fission reactor fuel assembly according to claim 1, wherein the porous nuclear fuel body defines a plurality of channels. 12. The nuclear fission reactor fuel assembly according to claim 11, wherein the porous nuclear fuel body has a plurality of particles defining the plurality of channels therebetween. 13. The nuclear fission reactor fuel assembly according to claim 1, wherein the porous nuclear fuel body has a plurality of pores, at least some of the plurality of pores being of a predetermined configuration for allowing at least a portion of the volatile fission product to escape the pores of the nuclear fuel body within a predetermined response time. 14. The nuclear fission reactor fuel assembly according to claim 1, wherein the porous nuclear fuel body has a plurality of pores for allowing at least a portion of the volatile fission product to escape within a predetermined response time of between approximately 10 seconds and approximately 1,000 seconds. 15. The nuclear fission reactor fuel assembly according to claim 1, wherein the porous nuclear fuel body has a plurality of pores for allowing at least a portion of the volatile fission product to escape within a predetermined response time of between approximately one second and approximately 10,000 seconds. 16. The nuclear fission reactor fuel assembly according to claim 1, wherein the porous nuclear fuel body has a cylindrical-shaped geometry. 17. The nuclear fission reactor fuel assembly according to claim 1, wherein the porous nuclear fuel body has a polygonal-shaped geometry. 18. The nuclear fission reactor fuel assembly according to claim 1, wherein the porous nuclear fuel body has a plurality of pores for acquiring the volatile fission product released by the burn wave in the traveling wave nuclear fission reactor. 19. The nuclear fission reactor fuel assembly according to claim 1, wherein the porous nuclear fuel body has a plurality of pores for transporting the volatile fission product through the porous nuclear fuel body. 20. The nuclear fission reactor fuel assembly according to claim 1, further comprising a reservoir coupled to the fluid control subassembly for receiving the volatile fission product. 21. The nuclear fission reactor fuel assembly according to claim 1, wherein the fluid control subassembly is configured for circulating a fission product removal fluid through the porous nuclear fuel body, at least a portion of the volatile fission product being removed from the porous nuclear fuel body while the fluid control subassembly circulates the fission product removal fluid through the porous nuclear fuel body. 22. The nuclear fission reactor fuel assembly according to claim 21, wherein the fluid control subassembly includes an inlet subassembly for supplying the fission product removal fluid to the porous nuclear fuel body. 23. The nuclear fission reactor fuel assembly according to claim 21, wherein the fluid control subassembly includes an outlet subassembly for removing the fission product removal fluid from the porous nuclear fuel body. 24. The nuclear fission reactor fuel assembly according to claim 21, further comprising a reservoir coupled to the fluid control subassembly for receiving the fission product removal fluid. 25. The nuclear fission reactor fuel assembly according to claim 21, further comprising a reservoir coupled to the fluid control subassembly for supplying the fission product removal fluid. 26. The nuclear fission reactor fuel assembly according to claim 1, wherein the porous nuclear fuel body defines a plurality of pores therein and wherein the fluid control subassembly is configured for circulating a gas through the pores of the porous nuclear fuel body. 27. The nuclear fission reactor fuel assembly according to claim 1, wherein the porous nuclear fuel body defines a plurality of pores therein and wherein the fluid control subassembly is configured for circulating a liquid through the pores of the porous nuclear fuel body. 28. The nuclear fission reactor fuel assembly according to claim 1, wherein the fluid control subassembly includes a pump. 29. The nuclear fission reactor fuel assembly according to claim 1, further comprising a pump integrally connected to the fluid control subassembly for pumping a fluid from the fluid control subassembly to the porous nuclear fuel body. 30. The nuclear fission reactor fuel assembly according to claim 1, further comprising a valve interposed between the enclosure and the fluid control subassembly for controlling flow of a fluid between the enclosure and the fluid control subassembly. 31. The nuclear fission reactor fuel assembly according to claim 30, wherein the valve includes a back-flow prevention valve. 32. The nuclear fission reactor fuel assembly according to claim 1, wherein the fluid control subassembly includes a valve. 33. The nuclear fission reactor fuel assembly according to claim 1, wherein the fluid control subassembly includes a controllably breakable barrier. 34. The nuclear fission reactor fuel assembly according to claim 33, wherein the barrier breaks at a predetermined pressure. 35. The nuclear fission reactor fuel assembly according to claim 33, wherein the barrier breaks by operator action. 36. The nuclear fission reactor fuel assembly according to claim 1, further comprising a controllably breakable barrier interposed between the enclosure and the fluid control subassembly. 37. A nuclear fission reactor fuel assembly configured for controlled removal of a volatile fission product released by a burn wave in the nuclear fission reactor fuel assembly, comprising:a heat-generating nuclear fuel body defining a plurality of pores having a volatile fission product therein;an enclosure enclosing the heat-generating nuclear fuel body therein;a fluid control subassembly coupled to the enclosure to control removal of at least a portion of the volatile fission product from the pores of the nuclear fuel body and to controllably remove at least a portion of the heat generated by the nuclear fuel body; anda control unit coupled to the fluid control subassembly to control operation of the fluid control subassembly to controllably release the volatile fission product in response to a selected parameter in the traveling wave nuclear fission reactor. 38. The nuclear fission reactor fuel assembly according to claim 37, wherein a fissile material forms the nuclear fuel body. 39. The nuclear fission reactor fuel assembly according to claim 37, wherein a fertile material forms the nuclear fuel body. 40. The nuclear fission reactor fuel assembly according to claim 37, wherein a mixture of fissile and fertile material forms the nuclear fuel body. 41. The nuclear fission reactor fuel assembly according to claim 37, wherein the fluid control subassembly controls release of the volatile fission product in response to a position of the burn wave in the traveling wave nuclear fission reactor. 42. The nuclear fission reactor fuel assembly according to claim 37, wherein the selected parameter includes a power level in the traveling wave nuclear fission reactor. 43. The nuclear fission reactor fuel assembly according to claim 37, wherein the selected parameter includes a neutron population level in the traveling wave nuclear fission reactor. 44. The nuclear fission reactor fuel assembly according to claim 37, wherein the selected parameter includes a volatile fission product pressure level in the traveling wave nuclear fission reactor. 45. The nuclear fission reactor fuel assembly according to claim 37, wherein the fluid control subassembly controls release of the volatile fission product in response to a time schedule associated with the traveling wave nuclear fission reactor. 46. The nuclear fission reactor fuel assembly according to claim 37, wherein the fluid control subassembly controls release of the volatile fission product in response to an amount of time the traveling wave nuclear fission reactor is operated. 47. The nuclear fission reactor fuel assembly according to claim 37, wherein the fluid control subassembly is configured for circulating a fission product removal fluid through the pores of the nuclear fuel body, at least a portion of the volatile fission product being removed from the pores of the nuclear fuel body while the fluid control subassembly circulates the fission product removal fluid through the pores of the nuclear fuel body. 48. The nuclear fission reactor fuel assembly according to claim 47, further comprising a reservoir coupled to the fluid control subassembly for receiving the fission product removal fluid. 49. The nuclear fission reactor fuel assembly according to claim 47, further comprising a reservoir coupled to the fluid control subassembly for supplying the fission product removal fluid. 50. The nuclear fission reactor fuel assembly according to claim 47, wherein the fluid control subassembly includes an inlet subassembly for supplying the fission product removal fluid to the pores of the nuclear fuel body. 51. The nuclear fission reactor fuel assembly according to claim 47, wherein the fluid control subassembly includes an outlet subassembly for removing the fission product removal fluid from the pores of the nuclear fuel body. 52. The nuclear fission reactor fuel assembly according to claim 37, wherein the fluid control subassembly is configured for circulating a heat removal fluid through the pores of the nuclear fuel body, at least a portion of the heat generated by the nuclear fuel body being removed from the nuclear fuel body while the fluid control subassembly circulates the heat removal fluid through the pores of the nuclear fuel body. 53. The nuclear fission reactor fuel assembly according to claim 52, further comprising a reservoir coupled to the fluid control subassembly for receiving the heat removal fluid. 54. The nuclear fission reactor fuel assembly according to claim 52, further comprising a reservoir coupled to the fluid control subassembly for supplying the heat removal fluid. 55. The nuclear fission reactor fuel assembly according to claim 52, further comprising a heat sink coupled to the fluid control subassembly and in heat transfer communication with the heat removal fluid for removing heat from the heat removal fluid. 56. The nuclear fission reactor fuel assembly according to claim 52, further comprising a heat exchanger coupled to the fluid control subassembly and in heat transfer communication with the heat removal fluid for removing heat from the heat removal fluid. 57. The nuclear fission reactor fuel assembly according to claim 37, wherein the fluid control subassembly simultaneously circulates a fission product removal fluid and a heat removal fluid. 58. The nuclear fission reactor fuel assembly according to claim 37, wherein the fluid control subassembly sequentially circulates a fission product removal fluid and a heat removal fluid. 59. The nuclear fission reactor fuel assembly according to claim 37, further comprising a pump integrally connected to the fluid control subassembly for circulating a fluid between the fluid control subassembly and the pores of the nuclear fuel body. 60. The nuclear fission reactor fuel assembly according to claim 37, wherein the fluid control subassembly includes a pump. 61. The nuclear fission reactor fuel assembly according to claim 37, further comprising a fission product reservoir coupled to the fluid control subassembly for receiving the volatile fission product. 62. The nuclear fission reactor fuel assembly according to claim 37, wherein the fluid control subassembly includes a plurality of first components that enable the fluid control subassembly to circulate a fission product removal fluid through the pores of the nuclear fuel body, at least a portion of the volatile fission product being removed from the pores of the nuclear fuel body while the plurality of first components enable the fluid control subassembly to circulate the fission product removal fluid through the pores of the nuclear fuel body. 63. The nuclear fission reactor fuel assembly according to claim 62, wherein the fluid control subassembly comprises a plurality of second components that enable the fluid control subassembly to circulate a heat removal fluid through the pores of the nuclear fuel body, at least a portion of the heat generated by the nuclear fuel body being removed from the nuclear fuel body while the plurality of second components enable the fluid control subassembly to circulate the heat removal fluid through the pores of the nuclear fuel body. 64. The nuclear fission reactor fuel assembly according to claim 63, wherein at least one of the first components and at least one of the second components are identical. 65. The nuclear fission reactor fuel assembly according to claim 37, wherein the fluid control subassembly includes a dual-purpose circuit for selectively removing the volatile fission product and heat from the nuclear fuel body. 66. The nuclear fission reactor fuel assembly according to claim 37, wherein the fluid control subassembly is configured for circulating a gas through the pores of the nuclear fuel body. 67. The nuclear fission reactor fuel assembly according to claim 37, wherein the fluid control subassembly is configured for circulating a liquid through the pores of the nuclear fuel body. 68. The nuclear fission reactor fuel assembly according to claim 37, wherein said enclosure is adapted to enclose a nuclear fuel body defining a plurality of channels. 69. The nuclear fission reactor fuel assembly according to claim 68, wherein the nuclear fuel body has a plurality of particles defining the plurality of channels therebetween. 70. The nuclear fission reactor fuel assembly according to claim 37, wherein the plurality of pores acquires the volatile fission product released by the burn wave in the traveling wave nuclear fission reactor. 71. The nuclear fission reactor fuel assembly according to claim 37, wherein one or more of the plurality of pores is of a predetermined configuration for allowing at least a portion of the volatile fission product to escape the nuclear fuel body within a predetermined response time. 72. The nuclear fission reactor fuel assembly according to claim 37, wherein the plurality of pores allows at least a portion of the volatile fission product to escape the nuclear fuel body within a predetermined response time of between approximately 10 seconds and approximately 1,000 seconds. 73. The nuclear fission reactor fuel assembly according to claim 37, wherein the plurality of pores allows at least a portion of the volatile fission product to escape the nuclear fuel body within a predetermined response time of between approximately one second and approximately 10,000 seconds. 74. The nuclear fission reactor fuel assembly according to claim 37, wherein the plurality of pores transports the volatile fission product through the nuclear fuel body. 75. The nuclear fission reactor fuel assembly according to claim 37, wherein the nuclear fuel body has a cylindrical-shaped geometry. 76. The nuclear fission reactor fuel assembly according to claim 37, wherein the nuclear fuel body has a polygonal-shaped geometry. 77. The nuclear fission reactor fuel assembly according to claim 37, wherein the fluid control subassembly includes a valve. 78. The nuclear fission reactor fuel assembly according to claim 77, wherein the valve includes a back-flow prevention valve. 79. The nuclear fission reactor fuel assembly according to claim 37, further comprising a valve interposed between the enclosure and the fluid control subassembly for controlling flow of a fluid between the enclosure and the fluid control subassembly. 80. The nuclear fission reactor fuel assembly according to claim 37, wherein the fluid control subassembly includes a controllably breakable barrier. 81. The nuclear fission reactor fuel assembly according to claim 80, wherein the barrier breaks at a predetermined pressure. 82. The nuclear fission reactor fuel assembly according to claim 80, wherein the barrier breaks by operator action. 83. The nuclear fission reactor fuel assembly according to claim 37, further comprising a controllably breakable barrier interposed between the enclosure and the fluid control subassembly.