Abstract
We perform direct numerical simulations of turbulent flow at friction Reynolds number Reτ≈ 500 - 2000 grazing over perforates plates with moderate viscous-scaled orifice diameter d+≈ 40 - 160 and analyse the relation between permeability and added drag. Unlike previous studies of turbulent flows over permeable surfaces, we find that the flow inside the orifices is dominated by inertial effects, and that the relevant permeability is the Forchheimer and not the Darcy one. We find evidence of a fully rough regime where the relevant length scale is the inverse of the Forchheimer coefficient, which can be regarded as the resistance experienced by the wall-normal flow. Moreover, we show that, for low porosities, the Forchheimer coefficient can be estimated with good accuracy using a simple analytical relation.
Original language | English |
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Pages (from-to) | 1241-1254 |
Number of pages | 14 |
Journal | Flow, Turbulence and Combustion |
Volume | 109 |
Issue number | 4 |
DOIs | |
Publication status | Published - 2022 |
Bibliographical note
In this article the author name Stefan Hickel was incorrectly written as Hickel Stefan. The original article has been corrected.Keywords
- Direct numerical simulation
- Forchheimer permeability
- Perforated plates
- Permeable walls
- Wall turbulence