Coolant Flow Rate Measurement Technique for Nuclear Power Reactor Control Systems

The problem of ensuring an error of no more than 1% in monitoring the coolant flow rate in the piping of the first loop of the reactor in nuclear power plants is examined. A method for measuring the coolant flow rate based on recording the γ-radiation during the variation of the oxygen activity of the coolant is proposed. A measurement device is created for recording bursts of γ-radiation which contain probes based on fiber optics and ways of placing it on the piping are described. To implement the proposed method, an optical flowmeter has been developed for monitoring the coolant flow in laminar and turbulent flow regimes at different temperatures. An optimum doping for the core of the fiber optic with germanium oxide is established for measurements of the coolant flow rate for different intensities of the oxygen activity. A method is proposed for recovery of the transmission of the optical fiber in measurements of the coolant flow rate in the presence of γ-radiation. A technique for measuring the coolant flow rate is examined in detail and features of its implementation are noted. Results from a study of the optical flowmeter on a test stand are presented.