Flow Regimes and Types of Solid Obstacle Surface Roughness in Turbulent Heat Transfer Inside Periodic Porous Media

The role of solid obstacle surface roughness in turbulent convection porous media is not well understood, even though it frequently used for heat transfer enhancement many applications. focus this paper to systematically study the influence on microscale flow physics and report its effect macroscale drag Nusselt number. Reynolds-averaged field numerically simulated using realizable k-ε model a through periodic medium consisting an in-line arrangement square cylinders with particles cylinder surface. Two regimes are identified respect particle height—fine coarse regimes. fine regime limited near-wall boundary layer around In regime, modify entire pore space medium. from rough obstacles fluid inside less than that smooth obstacle. there Total reduction also observed smallest height. spacing determines fractional area covered by recirculating, reattached, stagnating flow. As increases, two competing factors rate—increase due more reattached decrease fewer Decreasing porosity increasing Reynolds number amplify results suggest can be enhanced, if increase overcome. show which encountered corrosion, detrimental performance media.