苎麻纤维牵伸中加速点建模及其对成纱不匀的影响OA

Against the backdrop of the textile industry's transformation toward high-quality and high-value-added products,coupled with the global advocacy for green and sustainable development,ramie fibers exhibit tremendous application potential in the high-end textile field by virtue of their excellent mechanical properties and eco-friendly characteristics.However,their wide length distribution and high variability often result in poor yarn evenness,which limits the quality of ramie yarn.To solve this problem,this study established a force model of fibers in the drafting zone,proposed a quantitative method for calculating the fiber acceleration point during drafting,and verified the accuracy of the model through tracer fiber experiments. By analyzing the forces acting on fibers in the drafting zone,this study constructed a fiber force model,proposed a quantitative calculation method for the acceleration point of ramie fibers,and verified the model through tracer fiber experiments.During mechanical analysis,the study considered key parameters such as the friction coefficient between fibers,the pressure distribution in the roller nip,and the distribution of fast and slow-moving fibers.Experimental measurements under a drafting ratio of 4 and a roller gauge of 160 mm showed that the calculated acceleration points of fibers with lengths of 40 mm,70 mm,and 100 mm were consistent with the measured trends.As the fiber length increased,the acceleration point moved closer to the front roller nip,and its distribution became increasingly concentrated.Furthermore,the relationship between the acceleration point and yarn unevenness was investigated.The results indicated that when the difference between the roller gauge and fiber length increased from 110 mm to 150 mm,the acceleration point moved 12.9 mm away from the front nip,and the yarn unevenness increased by 27.4%.This demonstrates that a larger floating fiber zone leads to greater dispersion of acceleration points and higher yarn unevenness. This study provides a theoretical basis for optimizing drafting parameters(such as roller gauge)to improve the uniformity of ramie yarn.The proposed model and experimental approach offer practical insights for enhancing yarn quality in ramie spinning.