Numerical Study on the Solution Blowing Annular Jet and Its Correlation with Fiber Morphology

In this work, we investigated the turbulent airflow field of a solution-blowing annular jet using the computational fluid dynamic approach, captured the fiber flapping motion with a high-speed camera, and then correlated the fiber morphology with the physical quantities of the airflow field and fiber motion. The characteristics of the average flow fields of various nozzle configurations under different air pressures were calculated and compared. The simulations demonstrated that higher air pressure results in higher velocity and turbulent fluctuations. The experiments showed that polymer jet attenuation is due to the effects of stretching, bending instability, flapping motion, and solvent evaporation. The fiber diameters were found to decrease and become more uniform as the air pressure increased. However, the fiber morphology became worse, with the emergence of some fiber strands under even higher air pressures.