Speed of sound in helium-xenon mixtures in wide ranges of state parameters.

Using an ultrasonic interferometer in the temperature range from 293 to 393 K at pressures from 0.13 to 1.5–2.8 MPa, the speed of sound (U) was measured in helium-xenon gas mixtures with a helium content of 60.34; 71.72 and 85.32 at. %. The measurement errors of temperature, pressure, and speed of sound were ±20 mK, ±4 kPa, and ± (0.15–0.30) %, respectively. By approximating the experimental data for each composition, equations were obtained to describe changes of the speed of sound as a function of pressure and temperature over the entire measurement range. The existing reference and experimental data on the speed of sound in inert gases and He-Xe mixtures were analyzed. A method for calculating U of mixtures with a helium content above 71.7 at. % He to a temperature of 1500 K and a pressure of up to 7 MPa was developed. [ABSTRACT FROM AUTHOR]