Measurements of the thermal conductivity of propane at the approach of the coexistence line

We report the first measurements of the thermal conductivity of propane which show a steep increase of the thermal conductivity when approaching the coexistence line, in vapor and liquid phases. Measurements of the thermal conductivity of propane were performed in a coaxial cylinder cell operating in steady state conditions. The measurements of the thermal conductivity of propane were carried out along six isotherms below the critical temperature of propane (369.825 K). The present data cover the temperature range from 364.65 K to 369.12 K, and the pressure range 0.1-15 MPa. The analysis of the various sources of error leads to an estimated uncertainty of approximately ±3%, near the saturation curve. In order to analyze the subcritical enhancement of the thermal conductivity as a function of temperature and density at the approach of the saturation curve, background equations were used.