METHOD FOR DETERMINING REACTIVITY COEFFICIENTS IN NUCLEAR REACTORS

摘要

Method may be carried out at any steady state condition without interfering with the operation of the reactor, by the use of neutrons, temp., pressure or other detectors. The method involves the simultaneous measurement of the neutron fluctuation and the fluctuation of at least one other parameter (pressure, temp., etc.), then, using a known method, the frequency region is determined in which the causative relation exists between the fluctuation of the measured parameter and the neutron fluctuation. Also, using a known method the cross performance density function (CPSD(NS)) and the measured parameters cross performance function (APSD(S)) is set up. Then, knowing the reactor transfer function /G(if)/ formula (I) can be used to determine the reactivity coefft. - In (I), r = reactivity; s = the parameter in question (temp., pressure, etc.); G(if) = reactor transfer function; CPSD(NS) = cross performance density function; APSD(S) = cross performance density function of the parameter. - The integrals refer to the frequency region determined by causation methods.