Standing wave nuclear fission reactor and methods
Disclosed embodiments include nuclear fission reactor cores, nuclear fission reactors, methods of operating a nuclear fission reactor, and methods of managing excess reactivity in a nuclear fission reactor.
1 . A nuclear fission reactor core comprising:
a central core region including:
a plurality of fissile nuclear fuel assemblies;
ones of a plurality of fertile nuclear fuel assemblies; and
a plurality of movable reactivity control assemblies; and
a peripheral core region including:
others of the plurality of fertile nuclear fuel assemblies; and
a plurality of neutron absorber assemblies.
2 . The nuclear fission reactor core of claim 1 , wherein fertile material in the plurality of fertile nuclear fuel assemblies includes U 238 .
3 . The nuclear fission reactor core of claim 2 , wherein the U 238 includes at least one type of uranium chosen from natural uranium and depleted uranium.
4 . The nuclear fission reactor core of claim 2 , wherein the U 238 in ones of the plurality of nuclear fuel assemblies includes natural uranium and the U 238 in others of the plurality of nuclear fuel assemblies includes depleted uranium.
5 . The nuclear fission reactor core of claim 1 , wherein the plurality of fissile nuclear fuel assemblies include enriched fissile material.
6 . The nuclear fission reactor core of claim 5 , wherein the enriched fissile material includes U 235 .
7 . The nuclear fission reactor core of claim 1 , wherein the plurality of fissile nuclear fuel assemblies includes:
a plurality of enriched fissile nuclear fuel assemblies; and
a plurality of bred fissile nuclear fuel assemblies.
8 . The nuclear fission reactor core of claim 7 , wherein enriched fissile material in the plurality of enriched fissile nuclear fuel assemblies includes U 235 and bred fissile material in the plurality of bred fissile nuclear fuel assemblies includes PU 239 .
9 . The nuclear fission reactor core of claim 7 , wherein the peripheral core region further includes ones of the plurality of bred fissile nuclear fuel assemblies.
10 . The nuclear fission reactor core of claim 7 , wherein the peripheral core region further includes selected ones of the plurality of enriched fissile nuclear fuel assemblies having at least a predetermined burnup level.
11 . The nuclear fission reactor core of claim 7 , wherein the peripheral core region further includes selected ones of the plurality of bred fissile nuclear fuel assemblies having at least a predetermined burnup level.
12 . The nuclear fission reactor core of claim 7 , wherein the peripheral core region further includes ones of the plurality of bred fissile nuclear fuel assemblies having less than a predetermined burnup level.
13 . The nuclear fission reactor core of claim 1 , wherein:
the plurality of fissile nuclear fuel assemblies includes a plurality of bred fissile nuclear fuel assemblies; and
the core peripheral region includes a plurality of enriched fissile nuclear fuel assemblies having at least a predetermined burnup level.
14 . The nuclear fission reactor core of claim 13 , wherein the peripheral core region further includes ones of the plurality of bred fissile nuclear fuel assemblies.
15 . The nuclear fission reactor core of claim 14 , wherein the peripheral core region further includes selected ones of the plurality of bred fissile nuclear fuel assemblies having at least a predetermined burnup level.
16 . The nuclear fission reactor core of claim 14 , wherein the peripheral core region further includes ones of the plurality of bred fissile nuclear fuel assemblies having less than a predetermined burnup level.
17 . The nuclear fission reactor core of claim 1 , wherein at least one of the plurality of fissile nuclear fuel assemblies includes fissile material discharged from a nuclear fission reactor.
18 . The nuclear fission reactor core of claim 17 , wherein the plurality of fissile nuclear fuel assemblies that includes fissile material discharged from a nuclear fission reactor includes at least one re-clad fissile fuel assembly.
19 . The nuclear fission reactor core of claim 1 , further comprising a plurality of fuel assembly flow receptacles defining:
a first plurality of reactor coolant flow orifices in the central core region; and
a second plurality of reactor coolant flow orifices in the peripheral core region.
20 . The nuclear fission reactor core of claim 19 , wherein the first plurality of reactor coolant flow orifices includes a plurality of reactor coolant flow orifice groups.
21 . The nuclear fission reactor core of claim 20 , wherein flow rate through a selected one of the plurality of reactor coolant flow orifice groups is based upon a power profile at a radial location of the selected one of the plurality of reactor coolant flow orifice groups.
22 . The nuclear fission reactor core of claim 19 , wherein flow rate through the second plurality of reactor coolant flow orifices includes a predetermined flow rate based upon power level in the peripheral core region.
23 . The nuclear fission reactor core of claim 19 , wherein the first and second pluralities of reactor coolant flow orifices include fixed orifices.
24 . The nuclear fission reactor core of claim 19 , wherein the first and second pluralities of reactor coolant flow orifices include variable orifices.
25 . The nuclear fission reactor core of claim 19 , wherein the first and second pluralities of reactor coolant flow orifices include fixed orifices and variable orifices.
26 . The nuclear fission reactor core of claim 1 , wherein the plurality of movable reactivity control assemblies and the plurality of neutron absorber assemblies include hafnium hydride.
27 - 160 . (canceled)
161 . A nuclear fission reactor core comprising:
a central core region including:
a plurality of fissile nuclear fuel assemblies;
ones of a plurality of fertile nuclear fuel assemblies, wherein fertile material in the plurality of fertile nuclear fuel assemblies includes U 238 ; and
a plurality of movable reactivity control assemblies; and
a peripheral core region including:
others of the plurality of fertile nuclear fuel assemblies, wherein fertile material in the plurality of fertile nuclear fuel assemblies includes U 238 ; and
a plurality of neutron absorber assemblies;
a plurality of fuel assembly flow receptacles defining:
a first plurality of reactor coolant flow orifices in the central core region; and
a second plurality of reactor coolant flow orifices in the peripheral core region.
162 . The nuclear fission reactor core of claim 161 , wherein the U 238 includes at least one type of uranium chosen from natural uranium and depleted uranium.
163 . The nuclear fission reactor core of claim 161 , wherein the U 238 in ones of the plurality of nuclear fuel assemblies includes natural uranium and the U 238 in others of the plurality of nuclear fuel assemblies includes depleted uranium.
164 . The nuclear fission reactor core of claim 161 , wherein the plurality of fissile nuclear fuel assemblies include enriched fissile material.
165 . The nuclear fission reactor core of claim 164 , wherein the enriched fissile material includes U 235 .
166 . The nuclear fission reactor core of claim 161 , wherein the plurality of fissile nuclear fuel assemblies includes:
a plurality of enriched fissile nuclear fuel assemblies; and
a plurality of bred fissile nuclear fuel assemblies.
167 . The nuclear fission reactor core of claim 166 , wherein enriched fissile material in the plurality of enriched fissile nuclear fuel assemblies includes U 235 and bred fissile material in the plurality of bred fissile nuclear fuel assemblies includes PU 239 .
168 . The nuclear fission reactor core of claim 166 , wherein the peripheral core region further includes ones of the plurality of bred fissile nuclear fuel assemblies.
169 . The nuclear fission reactor core of claim 166 , wherein the peripheral core region further includes selected ones of the plurality of enriched fissile nuclear fuel assemblies having at least a predetermined burnup level.
170 . The nuclear fission reactor core of claim 166 , wherein the peripheral core region further includes selected ones of the plurality of bred fissile nuclear fuel assemblies having at least a predetermined burnup level.
171 . The nuclear fission reactor core of claim 166 , wherein the peripheral core region further includes ones of the plurality of bred fissile nuclear fuel assemblies having less than a predetermined burnup level.
172 . The nuclear fission reactor core of claim 161 , wherein:
the plurality of fissile nuclear fuel assemblies includes a plurality of bred fissile nuclear fuel assemblies; and
the core peripheral region includes a plurality of enriched fissile nuclear fuel assemblies having at least a predetermined burnup level.
173 . The nuclear fission reactor core of claim 172 , wherein the peripheral core region further includes ones of the plurality of bred fissile nuclear fuel assemblies.
174 . The nuclear fission reactor core of claim 173 , wherein the peripheral core region further includes selected ones of the plurality of bred fissile nuclear fuel assemblies having at least a predetermined burnup level.
175 . The nuclear fission reactor core of claim 173 , wherein the peripheral core region further includes ones of the plurality of bred fissile nuclear fuel assemblies having r less than a predetermined burnup level.
176 . The nuclear fission reactor core of claim 161 , wherein at least one of the plurality of fissile nuclear fuel assemblies includes fissile material discharged from a nuclear fission reactor.
177 . The nuclear fission reactor core of claim 176 , wherein the plurality of fissile nuclear fuel assemblies that includes fissile material discharged from a nuclear fission reactor includes at least one re-clad fissile fuel assembly.
178 . The nuclear fission reactor core of claim 161 , wherein the first plurality of reactor coolant flow orifices includes a plurality of reactor coolant flow orifice groups.
179 . The nuclear fission reactor core of claim 178 , wherein flow rate through a selected one of the plurality of reactor coolant flow orifice groups is based upon a power profile at a radial location of the selected one of the plurality of reactor coolant flow orifice groups.
180 . The nuclear fission reactor core of claim 161 , wherein flow rate through the second plurality of reactor coolant flow orifices includes a predetermined flow rate based upon power level in the peripheral core region.
181 . The nuclear fission reactor core of claim 161 , wherein the first and second pluralities of reactor coolant flow orifices include fixed orifices.
182 . The nuclear fission reactor core of claim 161 , wherein the first and second pluralities of reactor coolant flow orifices include variable orifices.
183 . The nuclear fission reactor core of claim 161 , wherein the first and second pluralities of reactor coolant flow orifices include fixed orifices and variable orifices.
184 . The nuclear fission reactor core of claim 161 , wherein the plurality of movable reactivity control assemblies and the plurality of neutron absorber assemblies include hafnium hydride.