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Chitosan has been widely studied for use in many areas, such as for its applications in the biomedical, engineering and pharmaceutical fields, as well as in industry, because of its unique properties, including biodegradability, antimicrobial activity, polycationic nature and biocompatibility. Thanks to the rapid development of materials science, chitosan applications are now possible in textiles. However, there are still many limitations of chitosan fibers in terms of their high electrostaticity, poor mechanical properties and high cost, which are obstacles that inhibit potential applications of chitosan fiber in the industry. Generally, in order to achieve the best performance with chitosan and enhance its commercial value, chitosan fibers are usually blended with long cotton fibers in the textile industry. Therefore, based on preliminary experiments and feedback from the industry, this study was carried out to further investigate the relationship between fiber length, fiber interaction and yarn performance. The results of this study would therefore help to reduce the production cost of yarns with the blending parameters used and also expand the utilization and applications beyond medical applications to fashion-based functional wear. The sliver-blending method offers better tensile properties of yarn samples, while the fiber-blending method offers higher uniformity of fiber distribution. This study would help to reduce the production cost of yarns by blending and also to expand the utilization and application not limited to fashion-based functional wear.

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. A theoretical analysis is developed to predict and explain the observed dependence of the mean lift and drag on a.

To study the effect of the cone angle of the hollow spindle in the nozzle of Murata vortex spinning (MVS) on yarn properties, the k‐ε turbulence model is employed to simulate the airflow patterns inside the different nozzles with different spindle cone angles. A set of corresponding spinning experiments is designed to verify numerical predictions. The simulation results show that some factors, such as the counter-rotating vortex pair (CVP) over the spindle, high supersonic zone in the inlet of the swirling chamber, and the distribution of wall shear stress (WSS) along the outer wall of the spindle caused by variation of the cone angle of the spindle, are significantly related to fluid flow, and consequently to MVS yarn properties. A rational cone angle (Case 2) can form an axisymmetric CVP and high WSS, which can ensure sufficient twisting of the yarn and produce high quality yarn. The experimental results, which yarn properties spun using 100% cotton, 100% polyester, and polyester 70∕cotton 30 blends with different nozzles, are well consistent with the numerical study.