СЕРПІМДІ ТОЛҚЫННЫҢ ЖЫЛДАМДЫҒЫНЫҢ НЬЮТОНДЫҚ ЕМЕС СҰЙЫҚТЫҢ ТЕМПЕРАТУРАСЫНА ТӘУЕЛДІЛІГІН ЗЕРТТЕУ

Abstract

In this study, an automated pulsed ultrasonic system was assembled to investigate the temperature dependence of the velocity of ultrasonic waves in liquids with properties close to those of biological fluids. The system includes a piezoelectric transducer with a resonant frequency of 5 MHz, a signal generator, an amplifier, an oscilloscope, a heater, an AC power source, a copper-constantan thermocouple, and a temperature controller. Temperature dependencies of the velocity and density of longitudinal waves at atmospheric pressure were measured in solutions of varying density, and the corresponding graphs were constructed for the first time. Using the experimentally obtained physical parameters, the temperature dependence of the elastic properties of the studied liquid sample under atmospheric pressure was calculated based on known physical laws and formulas. A single piezoelectric transducer was used both as the source of the elastic wave and as the receiver of the wave reflected from a mirror placed on the upper surface of the sample. The time taken by the ultrasonic wave to travel to and from the reflecting surface was determined by aligning the transmitted and reflected pulses displayed on the oscilloscope screen. To evaluate the accuracy of the measurements, distilled water – a well-studied liquid with a known ultrasonic wave speed – was used. The results obtained from the assembled system matched the reference data, confirming the system's accuracy and reliability.