A Facility for Investigating Ultrasound Velocity and Absorption in Light and Heavy Water at High Temperatures and High Pressures

An experimental facility was designed to study the velocity and absorption factor of ultrasound in light and heavy water at high temperatures (up to 550 degree C) and high pressures (as great as 550 atm.) using the continuous variable-baseline interferometer method. The facility is composed of an autoclave, a liquid nitric thermostat, systems for temperature and pressure measurements and control, mechanical and electrical systems of the acoustical interferometer, and a deaeration and filling unit. Due to the design features of the facility and the measuring technique, which ensure a low temperature gradient and a small ballast volume, the velocity and absorption factor of ultrasound can be simultaneously measured with a high degree of accuracy (0.05-0.09% and 7-10%, respectively), and their frequency dependences can be obtained in the range 0.5-10.0 MHz even in the critical region.