A Reactivity Meter and Its Application

Abstract

In order to measure reactivity from instant to instant during reactor operation, real time computation based on reactor kinetic equations must be made.The authors developed some reactivity meters capable of such computation based on the analog computer technique. After their characteristics were checked by an analog computer and a kinetic simulator, they were applied to reactor experiments and operation. It was found that the reactivity meter method for measurement of reactivity worth (especially for control rod calibration) is better than other current methods, and the reactivity meter can also serve as a tool in nuclear instrumentation of reactors for its ability to indicate reactivity even in reactor start up conditions.

A proposal for a subcritical reactivity meter based on Gandini and Salvatores' point kinetics equations for multiplying subcritical systems

“…It is important to notice that an algorithm for the obtainment of the subcriticality index (ζ) may be find analogously starting from (5).…”

“…This device is also commonly used in nuclear reactors at the initialization process, after refueling or during any interruption. In research facilities, a reactivity meter may be used in much more occasions [5].…”