Prediction of thermal conductivities for n-alkanes in liquid and supercritical phase

In this paper, a new model for thermal conductivity was proposed and applied for predicting thermal conductivities of n-alkanes in compressed liquid and supercritical phase. The new model was based on the modified Enskog theory and the Peng-Robinson Equation of State, with modifications made to improve the predictive accuracy of the former. Moreover, the new model can be utilized over a wide range of temperatures and pressures. The newly derived equation was then used to calculate the thermal conductivities of 16 n-alkanes (methane to n-hexadecane) in liquid and supercritical phase to check its accuracy. A comparison between the calculated data and the corresponding literature data was performed, yielding good agreement between values and an uncertainty of 6.2% (at the 95% confidence level). In addition, predicted performance of the present method was compared with that of previously reported models in the literature and the results indicated that the present model is generally superior to the conventional models, with respect to the accuracy. This suggests that the proposed model may be a useful tool for accurately calculating the thermal conductivities of liquid and supercritical n-alkanes. (C) 2020 Elsevier B.V. All rights reserved.