Computer Geometric Modeling and CFD Simulation of Air Permeability in Knitted Fabrics

The purpose of this study is to model the geometry of knitted fabric structures to predict air permeability using computational fluid dynamics (CFD). Rib 1×1 and interlock structures were simulated with varying loop densities and plain weft-knitted fabric models. The geometrical models of plain weft-knitted fabrics were studied using the Peirce model, the Leaf and Glaskin model, the Vassiliadis model, and Kurbak model, which considers the real shape of knit loops in three-dimensional space. A unit cell for each model was created with a single line of yarn path using SolidWorks software. Computational fluid dynamics analysis was then conducted on all samples using the SolidWorks Flow Simulation package. The numerical results demonstrated good agreement with the experimental data. The presented models provide a useful framework for predicting the air permeability of knitted fabrics by employing unit cells of the knitted fabric structure. This approach reduces operational complexity and significantly shortens solution time.