Numerical Study of Flow and Heat Transfer of High Knudsen Number Flow Regimes in Nanochannels Filled with Porous Media

Abstract

Considering the dependency of viscosity on Kn, a unified flow model for all flow regimes with different Kn was obtained. Applying the Dary Brinkman – Forchheimer flow model with the slip boundary condition, finite difference solutions for fully developed velocity distribution in a nanochannel of circular cross section, filled with porous media was presented. Convection heat transfer of the system, reflected in Nu was analyzed using the temperature jump boundary condition. It is shown that despite of the fact that in most of previous researches, Kn was assumed constant along the channel, the variations of Kn due to the pressure variations, have considerable effects on heat transfer and temperature distribution across the channel cross section.