FIELD: instrumentation.
SUBSTANCE: with the help of an ultrasonic converter they excite in two thin waveguides various zero modes of normal waves, measure coefficients of attenuation of each type of the wave in waveguides and calculate longitudinal and shift impedances of the investigated liquid, at the same time waveguides of the acoustic block are manufactured as thin strips of various thickness, they excite a Lamb wave zero mode in them, calibrate the acoustic block by means of serial measurement of Lamb wave zero mode attenuation coefficients in both waveguides with their serial submersion into two liquids with available longitudinal and shift impedances, from the produced equations they calculate coefficients that relate impedances of liquid with coefficient of Lamb wave absorption in waveguides, then waveguides are submerged into the investigated liquid, they measure coefficients of attenuation of Lamb wave zero mode in both waveguides and with the help of found numerical values of coefficients by available ratios they calculate longitudinal and shift impedances of the investigated liquid.
EFFECT: provision of possibility of automatic control of liquid state under conditions of their operation without measurement of zero mode of a horizontally polarised normal wave.
2 dwg
