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Fusion Science and Technology
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In transition: Commercializing fusion power
Commercial fusion power is closer than ever. There are now around 30 U.S. fusion companies, several of which claim to be on track to connect to the grid as early as the 2030s.
Tokamak and laser inertial confinement approaches benefit from decades of research at facilities such as the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory and ITER, with alternative concepts including stellarator, magnetic mirror, and Z-pinch confinement also making notable progress as private and government funding for fusion increases.
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).