Effect of gas molecular properties on the flow and heat transfer in the porous media with micro-/nanoscale structures

Gas transport and heat transfer in porous media is of scientific and technological interest due to its direct applicability in many industrial processes, environmental flows as well as biological applications. However, if the... [ view full abstract ]

Gas transport and heat transfer in porous media is of scientific and technological interest due to its direct applicability in many industrial processes, environmental flows as well as biological applications. However, if the length scales of the pores are small enough, the collisions between gas molecules and solid walls are much obvious, and both the velocity and temperature profiles behave differently with that predicted by conventional macroscopic theory. Gas permeability also differs from the intrinsic permeability of the porous media, which is caused by the Klinkenberg effect. In this study, pressure driven gas transport and heat transfer characteristics in porous materials with micro-/nanoscale pores has been investigated by the direct simulation Monte Carlo method. Different gas species are considered as the working fluid, and molecular structural parameters such as molecular diameter, mass, degrees of freedom and viscosity–temperature index on the macroscopic behavior of gases are investigated in detail. Pore scale flow patterns are obtained for different Knudsen numbers, and the apparent permeability for different species are integrated by Darcy law, which fit well with the available Klinkenberg correlations.