Nonequilibrium molecular dynamics study of molecular contributions to the thermal conductivity of carbon dioxide
نویسندگان
چکیده
We calculate the thermal conductivity of supercritical and liquid carbon dioxide using a recently developed nonequilibrium molecular dynamics (NEMD) algorithm for molecular fluids. We evaluate the translational, rotational, potential energy and force contributions to the heat flux separately. We find that at high density both the rotational contribution for a nonspherical molecule and the contribution from the total force acting on the molecule are important for predicting the thermal conductivity accurately. The NEMD results for the thermal conductivity agree well with experimental data. At a near critical state point, we observed a phase separation induced by the fictitious external field. The contribution to the thermal conductivity from the Lennard-Jones potential energy becomes important at this state point.
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