Measurement of the Kinematic Viscosity of the Eutectic LiF-AlF3

摘要

The kinematic viscosity of a eutectic salt mixture with the molar composition 0.855LiF-0.145AlF(3) at temperatures to 850A degrees C is measured by means of damped torsional vibrations of a cylinder with the experimental liquid. This salt mixture is of interest for separating actinides and lanthanides during reprocessing of spent nuclear fuel. Below 800A degrees C the behavior of the system is found to differ from that of a normal liquid. Such behavior is explained by precipitation on solid surfaces. The precipitated fraction of the material is evaluated as a function of temperature. An analytical expression is obtained for the kinematic viscosity at temperatures above 800A degrees C. The standard deviation of the kinematic viscosity evaluated assuming the dispersion to be independent of temperature equals 0.006 center dot 10(-6) m(2)/sec. The total error of measurement does not exceed 3%.