Nuclear reactor control method and apparatus

Abstract

A method for controlling a nuclear reactor is disclosed. The method includes providing a moderator zone in a core of the nuclear reactor, providing a fuel in the moderator zone, and providing one or more housings, each having a cavity, adjacent to the fuel. The method also includes allowing movement of a moderator between the moderator zone and the cavity of the one or more housings at a lower portion of the one or more housings. The method further includes confining moderator in the cavity of the one or more housings at an upper portion of the one or more housings.

What is claimed is: 
     
         1 . An apparatus for a nuclear reactor, comprising:
 a containment structure, with the following being disposed in the containment structure:
 a reactor core that includes a fuel assembly, the fuel assembly including a plurality of fuel elements; 
 a reflector zone that surrounds the reactor core; 
 neutron moderating material, wherein at least some of the neutron moderating material is a fluid and the fluid neutron moderating material is disposed in both the reactor core and the reflector zone; 
 a plurality of housings disposed adjacent to the fuel elements, each housing having a cavity and wherein a lower portion of each housing is open for movement of fluid neutron moderating material into and out of the cavity and an upper portion of each housing is closed for movement of fluid neutron moderating material into or out of the upper portion of the cavity; and 
 a plurality of cone assemblies that encircle the fuel elements; 
   wherein the fluid neutron moderating material moves from at least one of the plurality of housings to the reflector zone through the lower portion of at least one of the plurality of housings, and the fluid neutron moderating material moves from the reflector zone to at least one of the plurality of housings through the lower portion of at least one of the plurality of housings.   
     
     
         2 . The apparatus of  claim 1 , wherein each cone assembly has an inner cone assembly and an outer cone assembly. 
     
     
         3 . The apparatus of  claim 2 , wherein the inner cone assembly of each cone assembly encircles a portion of the fuel elements, and the outer cone assembly of each cone assembly encircles the inner cone assembly of each cone assembly. 
     
     
         4 . The apparatus of  claim 2 , wherein the inner cone assembly of each cone assembly includes a cone having a height that is about twice a height of each of the housings. 
     
     
         5 . The apparatus of  claim 4 , wherein each cone passes through one of a plurality of apertures disposed at a top portion of one of the plurality of housings. 
     
     
         6 . The apparatus of  claim 4 , wherein a lower portion of a first cone of a first inner cone assembly overlaps with an upper portion of a second cone of a second inner cone assembly, the lower portion of the first cone encircling the upper portion of the second cone. 
     
     
         7 . The apparatus of  claim 6 , wherein a passage is formed between the lower portion of the first cone and the upper portion of the second cone. 
     
     
         8 . The apparatus of  claim 2 , wherein the outer cone assembly of each cone assembly includes an interior cone and an exterior cone. 
     
     
         9 . The apparatus of  claim 8 , wherein the interior cone of the outer cone assembly of each cone assembly encircles a portion of the inner cone assembly of each cone assembly. 
     
     
         10 . The apparatus of  claim 8 , wherein the exterior cone of the outer cone assembly of each cone assembly encircles a portion of the interior cone of the outer cone assembly of each cone assembly. 
     
     
         11 . The apparatus of  claim 8 , wherein the interior cone of the outer cone assembly of each cone assembly has a height that is slightly less than a height of each of the housings. 
     
     
         12 . The apparatus of  claim 8 , wherein the exterior cone of the outer cone assembly of each cone assembly has a height that is less than a height of the interior cone of the outer cone assembly of each cone assembly. 
     
     
         13 . The apparatus of  claim 8 , wherein a cavity is formed between the interior cone and the exterior cone of the outer cone assembly of each cone assembly. 
     
     
         14 . The apparatus of  claim 8 , wherein the inner cone assembly of each cone assembly includes a cone, a passageway being formed between the cone of the inner cone assembly of each cone assembly and the interior cone of the outer cone assembly of each cone assembly. 
     
     
         15 . The apparatus of  claim 1 , wherein at least some of the neutron moderating material is in a liquid state and at least some of the neutron moderating material is in a gaseous state in both the reflector zone and in at least some of the cone assemblies. 
     
     
         16 . The apparatus of  claim 1 , wherein the fluid neutron moderating material disposed in the cone assemblies is heavy water (D 2 O). 
     
     
         17 . The apparatus of  claim 1 , wherein the fluid neutron moderating material disposed in the cone assemblies is light water (H 2 O).