Measurements and Theoretical Modeling of Tension Transmission of Yarns Traversing Cylinders From Diverse Spatial Angles

Abstract The yarn tension in the weaving region is critical to ensure the structure and quality of manufactured composite preforms. In the industrial production of three-dimensional (3D) woven carbon fiber preforms, thousands of carbon fiber yarns traverse cylindrical rods from diverse spatial angles. However, the effect of spatial angles on tension transmission remains unexplored. In this work, experiments and theoretical analyses are conducted to investigate the tension transmission of carbon fiber yarns interacting with cylindrical rods from various spatial angles. It is found that the output tension drops monotonically with increments in the wrap angle or cylinder radius. As the spatial angle is enlarged, the output tension gains a substantial increase. We derive a formula for the tension transmission of yarns over cylindrical surfaces that incorporates the effect of spatial angles and the power-law friction relation. The predictions from the theoretical model satisfactorily match the experimental data over a wide range of spatial angles, wrap angles, and cylinder radii. The model can provide theoretical guidance for precise tension control and could be applied in the tension control algorithms of weaving machines.