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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Leading the charge: INL’s role in advancing HALEU production
Idaho National Laboratory is playing a key role in helping the U.S. Department of Energy meet near-term needs by recovering HALEU from federal inventories, providing critical support to help lay the foundation for a future commercial HALEU supply chain. INL also supports coordination of broader DOE efforts, from material recovery at the Savannah River Site in South Carolina to commercial enrichment initiatives.
G. Ivan Maldonado, Paul J. Turinsky, David J. Kropaczek,Geoffrey T. Parks
Nuclear Science and Engineering | Volume 121 | Number 2 | October 1995 | Pages 312-325
Technical Paper | doi.org/10.13182/NSE95-A28567
Articles are hosted by Taylor and Francis Online.
The computer code FORMOSA-P (Fuel Optimization for Reloads Multiple Objectives by Simulated Annealing—PWR) has been developed to address pressurized water reactor (PWR) in-core nuclear fuel management optimization. Until recently, the optimization objectives available to the user included minimization of relative power peaking throughout the cycle, maximization of the end-of-cycle reactivity, and maximization of region-average discharge burnup. In addition, during an optimization, various core attributes (including the preceding objectives) can be optionally activated as constraints via penalty functions or to directly reject sampled loading patterns that violate established design limits. The underlying theoretical framework that enables the accurate and efficient calculation of objective and constraint values within the FORMOSA-P code is its higher order, nodal generalized perturbation theory (GPT) neutronics model. The utility of the FORMOSA-P code has been extended to include a traditionally out-of-core decision variable, namely, the fresh (i.e., feed) reload fuel enrichment. This is accomplished by formulating the feed enrichment as a GPT variable that can be adjusted concurrently with changes in the core loading pattern to enforce a target cycle length. This provides a reload designer with the capability to minimize feed enrichment during an in-core optimization while enforcing all other constraints (e.g., power peaking limit, cycle energy requirement, degree of eighth-core power tilt, discharge burnup limit, and moderator temperature coefficient limit).