Airflow simulation in nozzle for hairiness reduction of ring spun yarns. Part Ⅱ: Influence of nozzle parameters

摘要

In this present work we report the influence of nozzle parameters viz., axial angle and diameter of the nozzle in reducing yarn hairiness during NozzleRing spinning. Three nozzles having varying nozzle axial angles of 40°, 45°, and 50° and a constant nozzle diameter of 2.2 mm, and another nozzle having axial angle of 40° with a nozzle diameter of 2.6 mm were placed at a fixed distance of 10 cm below the front roller nip at ring frame for reducing yarn hairiness. Thirty tex carded cotton yarns were produced with and without nozzles. A CFD (computational fluid dynamics) modeling of airflow inside the nozzle indicates that a nozzle axial angle of 45° and 2.2 mm diameter gives best results in terms of reduction of S3 values. Swirling intensity plays a major role in reduction of yarn hairiness. The change of nozzle diameter plays a lesser role in reducing the S3 values. The difference in yarn diameter and bending rigidity values of NozzleRing yarns and ring yarns spun without nozzle are not statistically significant. Fabrics made from NozzleRing yarns show lesser pilling tendency as compared to those produced from yarns spun without nozzles.