Molecular dynamics simulation of heat conduction in near-critical fluids

Toshiyuki Hamanaka, Ryoichi Yamamoto, and Akira Onuki

Phys. Rev. E 71, 011507 – Published 20 January 2005

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 liquidlike (entropy-poor) clusters move toward the warmer boundary and gaslike (entropy-rich) regions move toward the cooler boundary in a temperature gradient. This counterflow results in critical enhancement of the thermal conductivity.