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November 8–12, 2025
Washington, DC|Washington Hilton
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DNFSB’s Summers ends board tenure, extending agency’s loss of quorum
Lee
Summers
The Defense Nuclear Facilities Safety Board, the independent agency responsible for ensuring that Department of Energy facilities are protective of public health and safety, announced that the board’s acting chairman, Thomas Summers, has concluded his service with the agency, having completed his second term as a board member on October 18.
Summers’ departure leaves Patricia Lee, who joined the DNFSB after being confirmed by the Senate in July 2024, as the board’s only remaining member and acting chair. Lee’s DNFSB board term ends in October 2027.
Atul A. Karve, Paul J. Turinsky
Nuclear Technology | Volume 131 | Number 1 | July 2000 | Pages 48-68
Technical Paper | Fuel Cycle and Management | doi.org/10.13182/NT00-A3104
Articles are hosted by Taylor and Francis Online.
As part of the continuing development of the boiling water reactor in-core fuel management optimization code FORMOSA-B, the fidelity of the core simulator has been improved and a control rod pattern (CRP) sampling capability has been added. The robustness of the core simulator is first demonstrated by benchmarking against core load-follow depletion predictions of both SIMULATE-3 and MICROBURN-B2 codes. The CRP sampling capability, based on heuristic rules, is next successfully tested on a fixed fuel loading pattern (LP) to yield a feasible CRP that removes the thermal margin and critical flow constraint violations. Its performance in facilitating a spectral shift flow operation is also demonstrated, and then its significant influence on the cost of thermal margin is presented. Finally, the heuristic CRP sampling capability is coupled with the stochastic LP optimization capability in FORMOSA-B - based on simulated annealing (SA) - to solve the combined CRP-LP optimization problem. Effectiveness of the sampling in improving the efficiency of the SA adaptive algorithm is shown by comparing the results to those obtained with the sampling turned off (i.e., only LP optimization is carried out for the fixed reference CRP). The results presented clearly indicate the successful implementation of the CRP sampling algorithm and demonstrate FORMOSA-B's enhanced optimization features, which facilitate the code's usage for broader optimization studies.
