Modeling the tensile behavior of fiber bundles with irregular constituent fibers

Abstract

In this paper, the effect of fiber dimensional irregularities on the tensile behavior of fiber bundles is modeled, using the finite element method (FEM). Fiber dimensional irregularities are simulated with sine waves of different magnitude. The specific stress-strain curves of fiber bundles and the constituent single fibers are obtained and compared. The results indicate that fiber diameter irregularity along fiber length has a significant effect on the tensile behavior of the fiber bundle. For a bundle of uniform fibers of different diameters, all constituent fibers will break simultaneously regardless of the fiber diameter. Similarly, if fibers within a bundle have the same pattern and level of diameter irregularity along fiber length, the fibers will break at the same time also regardless of the difference in average diameter of each fiber. In these cases, the specific stress and strain curve for the bundle overlaps with that of the constituent fibers. When the fiber bundle consists of single fibers with different levels of diameter irregularity, the specific stress-strain and load-elongation curves of the fiber bundle exhibit a stepped or "ladder" shape. The fiber with the highest irregularity breaks first, even when the thinnest section of the fiber is still coarser than the diameter of a very thin but uniform fiber in the bundle. This study suggests that fiber diameter irregularity along fiber length is a more important factor than the fiber diameter itself in determining the tensile behavior of a fiber bundle consisting of irregular fibers.

Improved Limiting Irregularity and Effective Fineness Models for Wool Yarn

“…This was done using a Single Fibre Analyser (SIFAN). The importance of within-fibre diameter variations on fibre mechanical properties has been examined in the literature (He & Wang, 2004 Ignoring the within-fibre variability may underestimate yarn limiting irregularity as well as effective fineness. This study examines how within-fibre diameter variation affects yarn limiting irregularity and effective fineness.…”

Nonlinear fiber-bundle-cells-based phenomenological modeling of human tissue samples

“…Results of testing and analyzing woven fabric samples showed that instead of linear fiber elements, nonlinear elements had to be used for modeling tensile behavior (Vas et al 2013 ). The use of such type of bundles can be found in some papers dealing with other structures as well (Goh et al 2013 ; He and Wang 2004 ). We had similar results when testing biological (plant, animal, and human) tissues (Hangody et al 2017 ).…”