void coefficient


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void coefficient

[′vȯid ‚kō·i‚fish·ənt]
(nucleonics)
A rate of change in the reactivity of a water reactor system resulting from a formation of steam bubbles as the power level and temperature increase.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
References in periodicals archive ?
Secondly, this particular reactor core has a negative void coefficient. "If you lose coolant, the reaction slows down, so it's no longer going to be an issue with giving off excess heat," Johnson explained.
This does not present a problem in a small reactor like EBR II but large fast reactor cores tend to have positive void coefficients, resulting in a runaway power excursion if the sodium boils.