Molecular Dynamics Simulation of Heat-Conducting Near-Critical Fluids

Toshiyuki Hamanaka; Ryoichi Yamamoto; Akira Onuki

doi:10.1103/physreve.71.011507

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Molecular Dynamics Simulation of Heat-Conducting Near-Critical Fluids

Toshiyuki Hamanaka·Ryoichi Yamamoto·Akira Onuki

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Abstract

Using molecular dynamics simulations, we study supercritical fluids near the gas-liquid critical point under heat flow in two dimensions. We calculate the steady-state temperature and density profiles. The resultant thermal conductivity exhibits critical singularity in agreement with the mode-coupling theory in two dimensions. We also calculate distributions of the momentum and heat fluxes at fixed density. They indicate that liquid-like (entropy-poor) clusters move toward the warmer boundary and gas-like (entropy-rich) regions move toward the cooler boundary in a temperature gradient. This counterflow results in critical enhancement of the thermal conductivity.

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Toshiyuki Hamanaka, Ryoichi Yamamoto, Akira Onuki. 2004-09-03. Molecular Dynamics Simulation of Heat-Conducting Near-Critical Fluids. https://doi.org/10.1103/physreve.71.011507

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