Time characteristics of reactor noise parameters and vibrations of the IBR-2 reactor moving reflectors

The energy noise of power pulses and the vibrations of the moving reflectors (MR) during the IBR-2 reactor operation from 1983-1986 at a power of 1-2 MW were experimentally studied. An analysis is made of the influence of various random processes due to MR on the time dependence of the principal parameters of reactor noises. The data were processed with statistical methods. It was shown that long period trends of reactor noises (within 4 years) depend essentially on a change of MR vibrations. The change of the parameters of noises during some cycles of measurement (going for less than 18 days) depend also on instability of the sodium component of the reactor noise. There is reported that the reactor noise charateristics during the whole period of operation of the reactor with the reactivity modulators of first generation (additional moving reflector shaped as a trident and main moving reflector - blade) meet the design requirements. This is mainly due to a high stability of operation of the principal systems of the reactor: the cooling system and the reactivity modulation one