Fiber movement during twisting in air vortex spinning

Abstract

In order to clarify the twisting mechanism of the air vortex spinning machine, this paper investigates the motion law of air vortex spinning fiber from the guided access into the twisting chamber during the whole process. While considering the bi-directional coupling effects of the airflow and fiber, the airflow–fiber fluid–solid coupling solution model of the guiding parts is established, and the fluid–solid bi-directional coupling solution platform is built based on ANSYS Workbench software. The movement trajectories of fibers in the process of single and double fibers entering the twisting zone from the guiding channel to the hollow spindle guiding channel were obtained, respectively. Through the fluid–solid coupling analysis, (1) under the action of airflow, the fiber movement is complex and variable, while the movement of the fiber affects the distribution of the surrounding airflow velocity and pressure. (2) Due to the asymmetric structure of the guiding channel, the airflow distribution on both sides of the fiber in motion is uneven, so that the fiber as a whole is wavy forward, and from time to time collisions occur with the tube wall. (3) The fibers are sucked into the twisting chamber under the effect of pressure difference, and the fibers are twisted under the combined effect of axial airflow and tangential airflow. The head end of the fiber enters the guided access in the middle of the hollow spindle under the guidance of the guiding pins. (4) In double fiber movement, there will be mutual adsorption, fibers becoming closer together, contact, stagger, separation and other phenomena that also affect the fiber in the airflow under the action of the twisting winding movement process.