Heat Transfer Predictions Using Accommodation Coefficients for a Dense Gas in a Micro/Nano-Channel

Abstract

The influence of gas-gas and gas-wall interactions on the heat flux predictions for a dense gas confined between two parallel walls of a micro/nano-channel is realized using combined Monte Carlo (MC) and Molecular Dynamics (MD) techniques. The accommodation coefficients are computed from explicit MD simulations. These MD coefficients are then used as effective accommodation coefficients in Maxwell-like boundary conditions in MC simulations. We find that heat flux predictions from MC based on these coefficients compare good with the results of explicit simulations except the case when there are hydrophobic gas-wall/gas-gas interactions. For this case an artificial wall was introduced in order to measure these MD accommodation coefficients at this artificial border. Good agreement is found then for both hydrophilic and hydrophobic gas-wall interactions and we show this by confronting the heat fluxes from explicit MD simulations with the the MC heat flux predictions for all the generic accommodation coefficients.