Ultrasonic Velocity and Attenuation Coefficient, Density and Adiabatic Compressibility of Petroleum Ether under High Hydrostatic Pressure

An apparatus for measuring ultrasonic velocity of liquid under different hydrostatic pressure was specially designed with the method of Pulse-Echo-overlap. Under the hydrostatic pressure ranged from 0.1 to 650 MPa, we measured ultrasonic velocity and attenuation coefficient of petroleum ether which is an important liquid-medium for transmitting pressure. An empirical formula of experimental data was obtained. The pressure dependence of ultrasonic velocity c is as follows: c=1. 063+6.77110-3p-2.28210-5p2+5.44910-8p3-6.07710-11p4+ 2.436 10-14p5 (0p700 MPa). In addition, we measured mass and compressed volume, getting the variation of density of petroleum ether with pressure: =0.6246+1.00710-3p-1.82310-6p2+2.54810-9p3-1.39310-12p4 (0p700 MPa). Finally, according to the equation c=(1/)1/2, the relation between hydrostatic pressure and adiabatic compressibility coefficient of petroleum ether were obtained.