Method of determining a fresh fuel bundle design for a core of a nuclear reactor

A method of determining a fresh fuel bundle design for a core of a nuclear reactor, comprising:

• employing at least one optimization routine to achieve a desired fuel bundle design meeting user-defined target conditions for up to N fresh fuel bundle groups of a given core being evaluated, the at least one optimization routine configured to:
• generate a response surface based on making single fuel rod-type exchanges in each (i,j) fuel rod location of each bundle of a given reference bundle design being evaluated for each of the N bundle groups, the response surface including a plurality of transfer functions;
• evaluate fuel rod type configurations of a plurality of candidate fresh fuel bundle design solutions, each candidate design solution generated by making multiple fuel rod-type exchanges made simultaneously across each of the N bundle groups using the generated response surface, with an objective function to converge to a desired fuel bundle design for each of the N bundle groups that satisfies the user-defined target conditions;
• and
• outputting data related to the desired fuel bundle design that satisfies the user-defined target conditions for each of the N bundle groups for display to a user,
• wherein generating the response surface includes
• perturbing a given reference bundle design for each of the N bundle groups by making a single fuel rod exchange at each (i,j) location of a given bundle in accordance with the given reference bundle design for each of the N bundle groups, wherein each of a plurality of fuel rod types stored in a fuel rod types database is selected to replace a given rod in each (i,j) location in a given bundle so as to generate a plurality of perturbed bundle designs for each of the N bundle groups,
• performing a bundle simulation of each of the bundles of the perturbed design to generate corresponding bundle simulation outputs,
• performing a core simulation of a virtual core loaded with the perturbed bundles of the perturbed design to generate core simulation outputs, and
• storing the bundle simulation outputs and core simulation outputs as data sets of the response surface, each data set of the response surface including a local response generated in accordance with a bundle simulation of a given perturbed bundle design due to the single fuel rod exchange and a global response generated in accordance with a core simulation of the perturbed bundle run through the bundle simulation.