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The paper deals with a CFD based study of the transverse permeability of a textile woven structure. The reported numerical investigation is preconditioned by both previous experimental and CFD study on jet systems. It is also based on detailed experimental investigation of the porous structure of single layer woven fabrics, made of staple fiber yarns. The flow in through-thickness direction of the woven structures is presented as jet systems, issuing from set of orifices. Two different types of jet system (3×3 jets and 5×5 jets) with two types of jet cross sections (square and circular), corresponding to two different woven structures, are simulated. An analysis is made in terms of the structure of the woven fabrics (area and shape of the interstices between the threads), the parameters of the flow passing through the textile (velocity profiles and velocity fields through isosurfaces), the role of the type of the jet systems, representing the flow and the influence of the shape of the interstices between the threads on the flow pattern. It was found that the applied approach could be effectively used for studying of the transverse permeability of the woven fabrics.

The paper presents computational fluid dynamics-based numerical simulation of the through-thickness air permeability of woven structures, applying the theory of jet systems. The flow through the interstices between the warp and weft threads is modeled as an ''in-corridor''-ordered jet system, formed by nine jets, issuing from nine pores of the woven structure. Fifteen cases were simulated and three different turbulence models were applied in the simulation: k-", k-! and Reynolds stress model. The five simulated woven structures were manufactured and their air permeability was measured experimentally. The performed validation of the numerical results with the experimental values of the air permeability showed very good correlation with the experimental results. The analysis and the verification showed that the method can be applied for further investigation not only of the woven fabrics' air permeability, but also for investigation of the flow after a textile barrier of a woven type.

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