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ANS Student Conference 2025
April 3–5, 2025
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Candidates for leadership provide statements: ANS Board of Directors
With the annual ANS election right around the corner, American Nuclear Society members will be going to the polls to vote for a vice president/president-elect, treasurer, and members-at-large for the Board of Directors. In January, Nuclear News published statements from candidates for vice president/president-elect and treasurer. This month, we are featuring statements from each nominee for the Board of Directors.
Hsiang-Shou Cheng, Ming-Shih Lu, David J. Diamond
Nuclear Technology | Volume 41 | Number 3 | December 1978 | Pages 283-298
Technical Paper | Reactor | doi.org/10.13182/NT78-A32114
Articles are hosted by Taylor and Francis Online.
The space-time effects associated with the void reactivity feedback in a commercial boiling water reactor were studied with the aid of the two-dimensional (R,Z) time-dependent coupled neutronics thermal-hydraulics computer code BNL-TWIGL. The statistical weight factor (SWF), which equates a point-reactor model to an appropriate space-dependent model, was used to quantify these effects. The SWF varied for the different reference reactor conditions and types of void perturbations considered. Its significant magnitude demonstrated that unless proper account is taken of multidimensional effects in plant transient calculations, the void feedback will be incorrect, and this will lead to errors in power and temperature. The presence of bypass void was found to increase the void reactivity feedback. The influence of other feedback mechanisms was studied, and a suggestion was offered for obtaining a measurement of the void reactivity coefficient.