International Journal of Thermophysics, Vol. 4, No. 3, 1983 Thermal Conductivity of Five Hydrocarbons Along the Saturation Line J. C. G. Calado, 1 J. M. N. A. Fareleira, l C. A. Nieto de Castro,1 and W. A. Wakeham 2 Received May 4, 1983 The paper presents the results of new, absolute measurements of the thermal conductivity of five alkanes as a function of temperature at their saturation vapor pressure. The alkanes studied include the four normal alkanes n-octane, n-nonane, n-undecane, and n-tetradecane as well as the branched alkane, iso-octane. The results, which extend over the temperature range 282-373 K, have an estimated uncertainty limit of 1.5% deriving mainly from a correction for the effects of radiation absorption in the measurement process. The results are employed to generate effective core volumes for the fluids studied which may be employed to predict the density dependence of the thermal conductivity by means of an existing correlation. KEY WORDS: alkanes; hydrocarbons; liquids; thermal conductivity. 1. INTRODUCTION In a series of earlier papers [1-5], we have described the design and development of a transient hot-wire instrument for accurate measurements of the thermal conductivity of liquids along their saturation line. In continuation of this work, we present here results of measurements upon a series of four normal alkanes (octane, nonane, undecane, and tetradecane) and one branched alkane (iso-octane) in the temperature range 282-373 K. For the first time in our work it has proved possible to correct the experimental data for the effects of radiative heat transport so that the present results enjoy a higher level of accuracy than hitherto, and prove to be consistent with independent measurements at elevated pressures [6, 7]. 1Centro de Quimica Estrutural, instituto Superior Tecnico, Lisbon, Portugal. 2Department of Chemical Engineering and Chemical Technology, Imperial College, London S.W.7., England. 193 0195-928X/83/0900-0193503.00/0 c~1983Plenum Publishing Corporation