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Atlanta, GA|Atlanta Marriott Marquis
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ANS joins others in seeking to discuss SNF/HLW impasse
The American Nuclear Society joined seven other organizations to send a letter to Energy Secretary Christopher Wright on July 8, asking to meet with him to discuss “the restoration of a highly functioning program to meet DOE’s legal responsibility to manage and dispose of the nation’s commercial and legacy defense spent nuclear fuel (SNF) and high-level radioactive waste (HLW).”
N. Spinks
Nuclear Science and Engineering | Volume 30 | Number 2 | November 1967 | Pages 182-187
Technical Paper | doi.org/10.13182/NSE67-A17329
Articles are hosted by Taylor and Francis Online.
From an empirical choice of the shadowing of one control-plate element by another, expressions are derived for the reactivity worth of systems of circumferential control plates. The expressions contain three parameters which are determined when independent calculations of three control systems have been made. The parameters can be expressed in terms of the worth of the complete control plate, the increase in reactivity due to unshadowing of an end of a control plate and the decay constant of the assumed exponentially decaying shadowing function. Application of the expressions to a particular reactor design, where circumferential control plates separate core from radial reflector, shows that the analysis is accurate for those situations where the number of control plates is not large. The analysis neglects neutron absorption by the edge of a control plate so that it underestimates reactivity worth in situations involving large numbers of control plates where the surface area of the plate edges becomes significant.