Simulation of the flow through woven fabrics

Filament-level three-dimensional simulations of the flow through single layer woven fabrics were done using FLUENTTM. For screen Reynolds numbers, Res, between 50 and 300, CFD simulations reproduce experimental measurements of wind tunnel screen pressure drops to within ±10%. Simulations of woven fabrics with geometric non-uniformities have also been undertaken. In these simulations one or more strands of the fabric is shifted laterally relative to its undisturbed location. If the filament displacement, normalized by the centre-to-centre separation between filaments, is ε, the enhancement in the flow rate through the enlarged opening in the fabric is given by approximately 2ε. A very simplified model of the geometry is consistent with this enhanced flow rate. The findings of this research are relevant to both wind tunnel and papermachine forming fabric design.