转杯复合纺成纱器内流场模拟及纱线质量分析

为探究转杯复合纺成纱器内流场特征及不同转杯速度对复合纱成纱质量的影响，对转杯复合纺纱成纱器进行三维建模，在Ansys 软件中模拟成纱通道尤其是纤维输送通道和转杯内的气流运动特性，解析成纱通道内流体压力和速度分布特征，并进行纺纱实验。结果表明：在相同工艺条件下，导丝管内的最低静压可达 - 9.8 kPa，转杯内负压在9 kPa 左右；纤维输送通道出口与转杯滑移面交汇处存在小部分高压区。气流在渐缩型的输棉通道中加速运动，出口处速度值达到386 m/s；输棉通道出口处的气流碰撞到滑移面后，分成2 股反方向的气流，沿着导丝管出口处作圆周运动；转杯速度与气流速度成正比，与转杯内静压成反比；转杯速度增加时，纱线断裂强力提高，断裂伸长率降低，条干不匀率增加，毛羽值减小。

Simulation of fluid flow in rotorcompositespinning unitand analysis on yarn quality

In order to explore flow field characteristics in the rotor spinning unit and the influence of different rotor speeds on thequality of composite yarn, a 3-D model of thespinning unit and numericalsimulation of the flow field were studied by Ansys software,including analysis of pressure and velocity distribution characteristics within the spinning channel.Rotor spun composite yarns were producedat different rotor speeds. The results show that under the same conditions, the minimum static pressure within the directing tube can be dropped to -9.8 kPa, and the negative pressure in the rotor is around 9 kPa. A small number of high pressure zones exist in theoutlet of the transfer channel and rotor slip plane.The speed of airstream accelerates from the transfer channel inlet to the outlet with the decrease of the pipe diameter, and reaches the largest value of 386 m/s at the outlet. The accelerated airstream impacts to the rotor slip plane from the transfer channel outlet, and is divided into two strands of the opposite direction airflows, and the airflows move as a circular motion along the outlet of the filament guide tube. Experimental results demonstrate that as the rotor speed increases, the airflow velocity increases, the static pressure decreases, thebreaking strength and evenness of composite yarn increase, and the breaking elongation and hairiness of composite yarn decrease.