2.14 - Properties of liquid metal coolants

Liquid metals, such as sodium (Na), lead (Pb) and lead–bismuth eutectic (Pb–Bi(e)), are considered as potential coolants for the fast spectrum nuclear reactors of the next generation. Intensive studies have been performed in different countries aiming at a better understanding of their properties needed for the design and safety analysis of nuclear installations. This article gives a brief review of the compilations and recommendations developed for the main thermophysical properties of Na, Pb, and Pb–Bi. The properties of theses coolants were measured in many laboratories, but mainly at the normal atmospheric pressure and at relatively low temperatures (except for Na). In general, the reliability of data is satisfactory, however, a large uncertainty still exists in some properties of Pb and Pb–Bi. A set of correlations for estimation of the main properties of Na, Pb, and Pb-Bi is proposed. For prognosis of the missing properties at high temperatures and pressures, a relevant equation of state (EOS) based on the proven physical models and available experimental data is suggested. The critical parameters are not well defined yet, and this hinders the EOS validation at high temperatures and pressures.