Numerical Modeling and Simulation of Turbulent Flow of Newtonian Fluids through Porous Media Using Rans and Les Approach

The numerical analysis of the mechanisms governing the flow in the porous region is of a priority interest for modeling porous media flows. The present study is a prerequisite for elaborating the efficient turbulence modeling techniques in porous media flows. The main objective of present study is to provide a detailed pore scale description of fluid flow and to analyze the formation of the coherent structures in the wake region close to the solid wall, subjected to the effects of the finescale turbulence. The computation was performed in a three dimensional representative elementary volume (REV) of porous media that are composed of a periodic array of circular cylinders. Two flow-modeling strategies were employed: steady RANS and the transient LES approach. In the RANS modeling framework both standard k– and low Re-k- turbulence models have been used. The porosity () of the porous REV has been varied from 0.3 to 0.8 and Reynolds number based on cylinder diameter (ReD) is varied from 100 to 40000. The effect of porosity and ReD on pore scale velocity distribution, overall macroscopic pressure gradient and turbulence statics have been investigated. The detailed flow characteristics obtained from the RANS and LES calculations within the porous REV have been compared. The results of comprehensive computations over three dimensional REV is compared with analytical solutions of the Darcy–Forchheimer law. The good agreement between computational predictions and the empirical laws demonstrated the validity of the numerical method to simulate the macroscopic flow behavior in porous media.