METHOD OF DETERMINING VOID RATE BY NONLINEAR ACOUSTIC RESONANCE SPECTROMETRY IN A BIPHASE MEDIUM AND APPLICATION IN A NUCLEAR REACTOR

摘要

The invention relates to a method of determining the void rate in a biphase gas/liquid medium, corresponding to the volume fraction of gas corresponding to the presence of bubbles in the liquid medium in a total volume of gas and liquid, characterized in that it comprises the following steps: - the placing of an elastic bulk wave resonator in contact and coupled acoustically with the biphase medium; - the measurement by nonlinear ultrasound resonance spectroscopy of the biphase medium comprising the scanning in terms of frequency and amplitude in a given frequency range and in a given amplitude range, of elastic bulk waves emitted and detected at said resonator placed in said medium and leading to the obtaining of a set of resonance curves exhibiting maxima; - the determination of a straight line defined by the set of maxima of said curves and of the slope (α) of said straight line; - the determination of the void rate on the basis of said slope. The invention also relates to the application of the method of determining the void rate in a gas/liquid biphase medium according to the invention, to a nuclear reactor that may be a fast neutron reactor.