Influence of nonlinear effects on the results of measuring the ratio of ultrasound absorption in a liquid by the cavity method

We consider the problem of the influence of nonlinear effects on the results of measuring the ratio of ultrasound absorption by using a resonator cavity. The relative amplitudes and the frequency response function of a nonlinear ultrasonic cavity with plane piezoelectric converters were calculated. The ranges of operating frequencies, at which the influence of nonlinear effects is significant, are determined. It is shown that in the case of nonlinear oscillations, the relaxation time of the fundamental harmonic is significantly shorter than that for the linear regime, which leads to overestimation of the measured ultrasound absorption rate.