基于双向耦合作用流场中异形筘内纬纱运动稳定性分析

为研究影响柔性纬纱纤维束在异形筘内流场的运动稳定性的因素，解决高速引纬过程断纬问题。考虑气流-纬纱两相耦合作用，通过基于任意拉格朗日-欧拉法建立柔性纬纱-流场耦合控制方程、数值模拟的方法得到了异形筘槽内瞬态流场的分布及纬纱运动特性，并通过高速摄像系统获得纬纱在流场中的位移验证了数值结果的正确性；详细讨论了辅助喷嘴的出口形状及尺寸等参数对纬纱运动特性的影响，结果表明:星形孔辅助喷嘴射流能够快速进入异形筘道与主喷嘴射流汇合，主气流的核心区域最长，引纬速度高，纬纱运动稳定性最好；随着喷孔直径的增大，纤维头端的弯曲变形增大，纬纱运动稳定性变差。可见小直径星型孔更适于高效引纬。

Analysis of motion characteristics of weft yarn in flow field based on bidirectional coupling

In order to analyze the factors affecting the stability of the motion of flexible weft fiber in the flow field and solve the problem of weft breakage during the high-speed weft insertion process. Considering the two-phase coupling of airflow and weft, flexible weft-airflow coupling control equation based on the arbitrary Lagrange-Euler method and numerical simulation were used to investigate the distribution of transient flow field and weft motion characteristics in the profiled reed. Then, the correctness of the numerical results verified by experimental displacements of weft in the flow field with a high-speed camera system. The influence of parameters such as the outlet shape and size of the auxiliary nozzle on the weft movement characteristics was discussed. The results show that the star-hole auxiliary nozzle jet can quickly expand into the profiled reed channel and converge with the main nozzle jet, the core area of the main airflow is the longest and the velocity of weft insertion is high. Hence, the stability of weft movement in airflow of star-hole auxiliary is the best. With the increase of orifice diameter, the bending deformation of the fiber head increases and the weft motion stability becomes worse.It is concluded that small size star-hole auxiliary nozzle has higher efficiency in weft insertion.