Fiber motion in rotor spinning unit airflow: Numerical simulation and experimental validation

Airflow-assisted manufacturing holds significant promise across various applications, including rotor spinning, where airflow is crucial for fiber transfer and ultimately affects yarn performance. This study introduces a three-dimensional model of flexible fiber motion within the flow field of a rotor spinning unit. The fiber is modeled as cylindrical segments connected by rigid joints, with the segments experiencing fluid torques and the joints subjected to fluid forces. The model accounts for the fiber bending and torsional deformation. Fiber motion is determined by solving the translational and rotational equations, alongside the fiber–wall interactions. Emphasis is placed on the fiber stripping process from the opening roller. Supported by the numerical methods validated through visualization experiments and further corroborated by spinning examinations, we advance the understanding of the motion behavior of fibers released from different initial positions in the rotor spinning unit, and specifically, delve into the impact of airflow patterns on fiber movement. The developed numerical methodology and findings are vital for optimizing rotor spinning unit design and effectively harnessing airflow technology in processing.