METHOD OF DETERMINATION OF NONLINEAR ULTRASONIC PARAMETER OF LIQUIDS AND DEVICE FOR ITS IMPLEMENTATION Russian patent published in 2014 - IPC G01N29/02 G01S15/88 

FIELD: physics, acoustics.

SUBSTANCE: invention relates to the field of physical acoustics and is intended for study of ultrasonic properties of liquids, such as marine water and various process fluids. The method includes the generation and reception of signals of minimum two different frequencies, passed through the measuring section, by a single emitter operating in the mode "generation - reception". The time interval between impulses is selected so that the previous impulse has been damped. The measuring section is a distance between the emitter surface and the reflecting surface located axially with it in a parallel plane. The signals area filtered at the difference frequency with measurement of amplitudes of pressure of waves of difference frequency and then the parameter of nonlinearity is determined by the value of nonlinear ultrasonic parameter (ε) according to the formula ε=ε₀[P_Ω(r)/P_Ω0(r)], where ε - value of nonlinear ultrasonic parameter in the studied medium, P_Ω(r) - amplitude of pressure of the wave of difference frequency at the distance r in the studied medium, and ε₀ and P_Ω0(r) - are the values of nonlinear ultrasonic parameter and amplitude of pressure of the wave of difference frequency at the distance (r) in known medium, respectively, determined earlier by calibration.

EFFECT: improvement of resolving ability spatially, sensitivity to manifestation of weak nonlinear effects, and also improvement of reliability of measuring at a small measuring base due to a possibility to accumulate nonlinear effects at a great distance of run of pump waves, which is restricted only by attenuation distance of the sound impulse.

2 cl, 3 dwg