Non-linear fast feedback innTHE DOUNREAY FAST REACTOR Its measurement and an explanation of its origin

摘要

To estimate the kinetic behaviour of the reactor under a wide range of conditions, including fault conditions, it is necessary to extrapolate the reactivity feedback to reactor powers beyond the normal range. Such extrapolation is simple if the feedback varies linearly with power.nEarly measurements on the Dounreay Fast Reactor showed that the temperatureinduced reactivity feedback was negative, linear and approximately as calculated. More recently the measurements showed that under certain conditions the fast acting feedback was reduced in amplitude and that its measured magnitude varied with the magnitude of the perturbation used in the measurement.