Theoretical modeling of spacer-yarn arrangement for warp-knitted spacer fabrics and experimental verification

Abstract

Different surface structure of spacer fabric implies different spacer yarn arrangement and therefore the compression resistance of fabric. The spacer yarns' arrangement modeling of warp knitted spacer fabrics having identical parameters (thickness, density, material etc.) but different surface structures on double-needle-bar Raschel knitting machine is presented in the study. In a sample, there are several spacer yarns' inclination directions, which differ according to surface structures despite the same lapping movement of spacer guide bars. To simplify the arrangement modeling, it was considered that there was only one inclination angle in a sample, and that was weighted average angle η. The theoretical compression curves were obtained by substituting η into derived equation then simulating by Matlab. To verify proposed arrangement modeling, the compression experiment was done to gain experimental compression curves. The curves of theoretical simulation and experiment of each sample were compared in a figure and the curves exhibited agreement with each other while there were still some deviations derived from the partial approximate substitutions of equations and arrangement angles, as well as the differences between theoretical and actual fabric parameters after removing from knitting machine such as thickness, density, and so on.