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A numerical study on the laminar vortex shedding frequency on a porous and partially porous circular tube has been made. Porous tubes characterised by an inner and outer diameter of the porous zone are subjected to a uniform flow. The porous region is divided in eight segments of 45° with a different porous structure. The porous behaviour has been modelled by a Darcy-equation. To ensure a laminar vortex shedding, the Reynolds number has been chosen between 40 and 200. The influence of the Reynolds number and the properties of the porous zone (thickness, pressure drop), characterised by a dimensionless thickness Λ and a Darcy number Da on vortex shedding frequency (dimensionless Strouhal number Sr) and volume flow through the porous zone (dimensionless volume flow Π) has been analysed.
CFD, cylinder, frequency, porous, segment, vortex shedding
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