Mathematical Simulation of Fabric Bagging

A mathematical model is developed to simulate the rheological behavior of fabric bagging. The model is based on the assumption that stress-strain relationships in fabric consist of three essential components: elastic deformation and viscoelastic deformation of fibers and the friction between fibers and yarns within the fabric structure. The nonlinear strain of the fabric, the elastic and viscoelastic deformation of fibers, and interfiber friction during the bagging process have been taken into account in the model. By specifying the fundamental parameters of fiber mechanical properties and yarn-fabric structural features, the model is able to predict fabric bagging behavior under test conditions, such as loading and unloading processes in each cycle, change of bagging force with cycles, relative contributions of the three components (elasticity, viscoelasticity, and frictional forces) in each cycle, and residual bagging height in each cycle. A comparison of theoretical predictions with experimental measurements for two wool fabrics with different structures reveals good agreement between them. The results indicate that the mathematical model is able to quantitatively simulate fabric bagging rheological behavior and predict fabric bagging performance by specifying basic fiber mechanical properties and yarn-fabric structural parameters.