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MARVEL PDSA approval could serve as blueprint
MARVEL, the Microreactor Applications Research Validation and Evaluation project at Idaho National Laboratory, has had its preliminary documented safety analysis approved by the Department of Energy, marking a milestone in its development and serving as a potential outline for other microreactors in development.
Dawk Hwan Ahn, Samuel H. Levine
Nuclear Technology | Volume 71 | Number 3 | December 1985 | Pages 535-547
Technical Paper | Fission Reactor | doi.org/10.13182/NT85-A33676
Articles are hosted by Taylor and Francis Online.
A new method has been developed to automatically reload and deplete a pressurized water reactor (PWR) so that both the enriched inventory requirements during the reactor cycle and the cost of reloading the core are minimized. This is achieved through four stepwise optimization calculations: (a) determination of the minimum fuel requirement for an equivalent three-region core model, (b) optimal selection and allocation of fuel assemblies for each of the three regions to minimize the reload cost, (c) optimal placement of fuel assemblies to conserve regionwise optimal conditions, and (d) optimal control through poison management to deplete individual fuel assemblies to maximize end-of-cycle keff. The new method differs from previous methods in that the optimization process automatically performs all tasks required to reload and deplete a PWR. In addition, the previous work that developed optimization methods principally for the initial reactor cycle was modified to handle subsequent cycles with fuel assemblies having burnup at beginning of cycle. Application of the method to the fourth reactor cycle at Three Mile Island Unit I has shown that both the enrichment and the number of fresh reload fuel assemblies can be decreased and fully amortized fuel assemblies can be reused to minimize the fuel cost of the reactor.