Comparison of the thermal conductivities of water and heavy water

New measurements of the thermal conductivity of H2O and D2O have been performed from critical temperature up to 5100C and from atmospheric pressure up to 100 MPA. As these measurements have been made with the same cell, a precise analysis of the isotopic effect as a function of temperature and density is possible. Our analysis is presented in terms of corresponding states. It is shown that the critical thermal conductivity excesses for H2O and D2O reduced by their respective background thermal conductivity terms are represented by single reduced isotherms