Patent Number: 
Section: claims

1. A method of improving nuclear reactor performance, comprising:implementing an operational solution generated for the nuclear reactor using an objective function including at least one of a spatially dependent and exposure dependent constraint accounting for a problem with operation of the nuclear reactor, the problem being an unintended change in reactor performance or configuration and capable of being represented by the at least one of the spatially dependent constraint and the exposure dependent constraint in the objective function, and the objective function producing a figure of merit for the operational solution. 2. The method of claim 1, wherein the constraint is a spatially dependent power distribution constraint. 3. The method of claim 2, wherein the spatially dependent power distribution constraint accounts for one or more leaking fuel rods. 4. The method of claim 2, wherein the spatially dependent power distribution constraint accounts for one or more corrosion-susceptible locations. 5. The method of claim 2, wherein the spatially dependent power distribution constraint accounts for degradation in reactor flow. 6. The method of claim 2, wherein the spatially dependent power distribution constraint accounts for degraded exit steam quality. 7. The method of claim 1, wherein the constraint is an exposure dependent constraint. 8. The method of claim 7, wherein the exposure dependent constraint accounts for exposure dependency of thermal limit. 9. The method of claim 7, wherein the exposure dependent constraint accounts for one or more parameters having exposure dependency when the nuclear reactor operates beyond an anticipated cycle length. 10. The method of claim 1, further comprising:modifying the constraint based on performance of the nuclear reactor following the implementing step; andrepeating the implementing step using the modified constraint. 11. A method of improving nuclear reactor performance, comprising:generating an operational solution for the nuclear reactor using an objective function including at least one of a spatially dependent and exposure dependent constraint accounting for a problem with operation of the nuclear reactor, the problem being an unintended change in reactor performance or configuration and capable of being represented by the at least one of the spatially dependent constraint and the exposure dependent constraint in the objective function, the objective function producing a figure of merit for the operational solution, andimplementing the operational solution. 12. The method of claim 11, wherein the constraint is a spatially dependent power distribution constraint. 13. The method of claim 12, wherein the spatially dependent power distribution constraint accounts for one or more leaking fuel rods. 14. The method of claim 12, wherein the spatially dependent power distribution constraint accounts for one or more corrosion-susceptible locations. 15. The method of claim 12, wherein the spatially dependent power distribution constraint accounts for degradation in reactor flow. 16. The method of claim 12, wherein the spatially dependent power distribution constraint accounts for degraded exit steam quality. 17. The method of claim 11, wherein the constraint is an exposure dependent constraint. 18. The method of claim 17, wherein the exposure dependent constraint accounts for exposure dependency of thermal limit. 19. The method of claim 17, wherein the exposure dependent constraint accounts for one or more parameters having exposure dependency when the nuclear reactor operates beyond an anticipated cycle length. 20. The method of claim 11, further comprising:developing the constraint; anddeveloping the objective function including the constraint. 21. The method of claim 20, wherein the developing the objective function step modifies a pre-existing objective function by adding the constraint to the objective function. 22. The method of claim 11, wherein the generating step is a constraint based optimization operation. 23. The method of claim 11, further comprising:modifying the constraint based on performance of the nuclear reactor following the implementation of the operational solution; and repeating the generating step using the modified constraint. 24. A method of improving nuclear reactor performance, comprising:generating an operational solution for the nuclear reactor using an objective function including a constraint tailored to a problem with operation of the nuclear reactor, the problem being an unintended change in reactor performance or configuration and capable of being represented by the at least one of the spatially dependent constraint and the exposure dependent constraint in the objective function, the objective function producing a figure of merit for the operational solution, andimplementing the operational solution.