@InProceedings{ Verleye.Croce.Griebel.ea:2008*1, author = {B. Verleye and R. Croce and M. Griebel and M. Klitz and S.V. Lomov and G. Morren and H. Sol and I. Verpoest and D. Roose}, title = {Permeability of textile reinforcements:simulation; influence of shear, nesting and boundary conditions; validation}, booktitle = {Proceedings of the 9th International Conference on Flow Processes in Composite Materials}, year = {2008}, publisher = {International Conference on Flow Processes in Composite Materials edition}, annote = {series}, volume = {9}, address = {Qu\'ebec}, abstract = {A fast an accurate simulation tool for the permeability of textiles is presented, based on a finite difference discretisation of the Stokes equations. Results for single layer, multi layer and sheared models are discussed. The influence of intrayarn flow and periodic respectively wall boundary conditions are considered. Simulated permeability values are compared with experimental data. For the creation of the textile model the WiseTex software is used, which implements a generalised description of internal structure of textile reinforcements on the unit cell level. A finite difference Navier-Stokes solver, NaSt3DGP, was developed at the Institute for Numerical Simulation at the University of Bonn. The flow solver employs a Chorin projection on a staggered grid for the solution of the Navier-Stokes. In the staggered grid approach, the pressure is discretised at the centre of the cells, while the velocities are discretised on the edges. This discretisation leads to a strong coupling between pressure and velocities, and therefore avoids the occurrence of unphysical oscillations in the pressure. The experimental validation is performed with a highly automated central injection rig PIERS.}, pdf = {http://wissrech.ins.uni-bonn.de/research/pub/croce/FlowProcCompMat2008.pdf} }