Thermal Conductivity of Gaseous and Liquid Hydrogen

Abstract

The thermal conductivity of gaseous and liquid hydrogen has been measured with a guarded horizontal flat‐plate calorimeter at temperatures between 17 and 200°K and at pressures to 15 MN/m2. The data have been analyzed as a function of density at fixed temperatures and as a function of temperature at fixed densities. Outside the critical region the thermal conductivity of both the gas and the liquid increases continuously with temperature and density. In the compressed liquid the temperature derivative at fixed density is positive and unusually large compared to that for most other simple liquids. In the critical region the thermal conductivity increases rapidly with both temperature and density as these parameters approach their critical values. The thermal conductivity of the dilute gas is consistent with the kinetic theory expression, K 0 (T) = f ME (T)C υ 0 (T)η 0 (T) / M , and the dilute gas viscosities to better than 3%.