The Thermal Conductivity of Fluid Air

Based on available experimental data, the thermal conductivity of fluid air has been critically evaluated. A new set of recommended values is presented covering a pressure range from 1 to 1000 bar and a temperature range from 70 to 1000 K. Using the concept of residual thermal conductivity the recommended values are described by a 13-parameter equation of state in terms of temperature and density which may be applied up to a density of 900 kg/m3. From comparisons of all data sources, the uncertainty of the recommended values was estimated to be below ±4%. Additional experiments are needed, especially in the subcritical region of liquid air.