Thermal conductivity of gaseous and liquid n-pentane

Abstract Absolute measurements of the thermal conductivity of n-hexane performed in a coaxial cylinder cell operating under steady state conditions are reported. The measurements of the thermal conductivity of n-hexane were carried out in the liquid along nine quasi-isotherms below the critical temperature ( T c  = 507.82 K), in the low-pressurized gas at some temperatures below the critical temperature, and in the compressed gas along nine quasi-isotherms above the critical temperature. Additional thermal conductivity measurements were also performed in the liquid and the gas along the isobar at 0.101325 MPa and in the vapor close to the saturation curve for temperatures below the boiling temperature ( T b  = 341.865 K). The present 577 data cover roughly the temperature range from 293 K to 612 K and the pressure range from 0.01 to 40 MPa. An analysis of the different sources of error leads to an estimated uncertainty of approximately 1.5%. The experimental results are correlated separating the additional contributions of the temperature effect and the density effect (in the density range from 0 to 670 kg m −3 ). A brief comparison is shown with previous experimental measurements of the thermal conductivity of n-hexane.