Open AccessDETERMINATION OF THE NONLINEAR PARAMETER AND INTERNAL PRESSURE IN A LIQUID BY THE ACOUSTIC METHOD
Author(s) -
Jr. Dudzinskii,
Н. С. Титова,
N. V. Manicheva,
Anna Zakharova
Publication year - 2021
Publication title -
trudy odesskogo politehničeskogo universiteta
Language(s) - English
Resource type - Journals
eISSN - 2223-3814
pISSN - 2076-2429
DOI - 10.15276/opu.1.63.2021.09
Subject(s) - acoustics , harmonics , materials science , nonlinear system , signal (programming language) , amplitude , linearity , harmonic , acoustic wave , acoustic resonance , sound pressure , optics , physics , optoelectronics , computer science , quantum mechanics , voltage , resonator , programming language
An acoustic method is proposed for assessing the molecular properties of a liquid, determining the nonlinear parameter of liquids from the ratio of the first and second harmonics when the acoustic wave changes, and using this parameter to measure the internal pressure. In addition, the proposed method measures intermolecular distances for the studied liquids. In organ fluids, the effects of sound scattering and wave interaction are enhanced. In body fluids, at the molecular level, there is a small amount of microscopic bubbles. This leads to the appearance of the phenomenon of cavitation. These phenomena can be harmful, but not always. There are devices for biological and pharmaceutical technologies, medical devices that successfully use these effects. The paper presents a functional diagram of the experiment, identifies the oscillograms of acoustic signals of finite amplitude at different distances from the emitter. The same devices based on quartz plates 25 mm in diameter with a resonance frequency of 3 MHz were used as the emitter and receiver. This difference of approximately three times the resonance frequencies of the sensors and the acoustic signal ensures the linearity of the amplitude-frequency response of both sensors. Nonlinear acoustic methods are a global trend in biomedical research, as they open up new opportunities and prospects in the development of medical devices. The appearance of higher harmonics in the curvature of the initial harmonic wave of finite amplitude can be used for express analysis of the physical properties of pure liquids and especially aqueous solutions of organic substances. This method of experimental determination of the nonlinear parameter and internal pressure in a liquid is more convenient than the static one, since it does not require the use of high excess static pressures. The proposed acoustic method gives less error than the dynamic one. The accuracy of such a determination can be sufficient to judge the change in the intermolecular interaction in liquids.