A prediction model for thermal conductivity of supercritical carbon dioxide

Abstract

Thermal conductivity of supercritical carbon dioxide (scCO₂) plays a pivotal role in designing various industrial and energy devices. However, there is currently no universally accepted theoretical model to accurately describe its thermal conductivity. In this study, based on the thermal conductivity models for gaseous and liquid matters and kinetic theory, we propose a concise model to predict the thermal conductivity of supercritical fluids. This model effectively captures the thermal conductivity behavior of scCO₂, yielding the average absolute relative deviation of approximately 13.7% compared to the experimental data. With higher temperature and pressure, the prediction deviation of the model will be lower. Comparison with the other fluid thermal conductivity models and molecular dynamics (MD) simulation demonstrates that our model outperforms in prediction accuracy. This novel model presents a promising approach for accurately predicting the thermal conductivity of scCO₂.