Numerical simulation into influence of airflow channel quantities on melt-blowing airflow field in processing of polymer fiber

To obtain better airflow field characteristics of melt-blowing and acquire slender melt-blowing fiber, a new die with multi-channel of melt-blowing airflow was designed. The airflow field under the spinneret hole of the melt-blowing die was simulated and analyzed using computational fluid dynamics method, and distribution rules of the ordinary die and the new die on the airflow field along the spinning centerline were compared and discussed. The melt-blowing fiber diameter distribution for the ordinary die and the new die was numerically calculated using a stretching model of the melt-blowing fiber. In contrast with an ordinary die, the new melt-blowing die enhances the average speed in main stretching zone by 89.8% and increases the peak speed by 50.4%. The higher airflow temperature of new die improves the softening degree and melting fluidity of the polymer. Meanwhile, the smaller turbulence intensity and the reverse speed of the new die make airflow more stable and reduce disturbance and adhesion of the fiber, and a larger pressure difference and a peak pressure can accelerate the refinement and attenuation of the fiber. The new melt-blowing die with airflow multi-channel is conducive to extension, which is a better choice in the manufacturing process of nonwoven melt-blowing fibers.