解析法评价旋转气流对喷气涡流纱的加捻强度

在对喷嘴内部流场数值模拟的基础上通过解析法研究旋转气流对喷气涡流纱加捻的强度。研究结果表明:旋转气流对喷气涡流纱的加捻强度是喷孔数目、喷孔倾角、喷孔直径、喷嘴直径、空心锭外径、喷孔出口速度(即喷嘴气压)、空心锭入口与喷嘴入口间距、尾端自由端纤维倒伏空心锭上部的高度、纱线直径等的函数。喷孔出口速度增加,旋转气流加捻强度增强;加捻喷嘴直径减小,旋转气流加捻强度增大;空心锭入口与喷嘴入口间距增加,旋转气流加捻强度减小;空心锭外径增加,旋转气流加捻强度增加。数值计算结果表明解析模型的有效性。

Evaluating the strength of the vortex twist acting on the yarn in air jet vortex spinning

The strength of the vortex twist acting on the air jet vortex yarn was investigated by analytical model based on simulating the flow field inside the nozzle.The result shows that the strength of the vortex twist acting on the air jet vortex yarn is regarded as a function of the number of jet orifices,jet orifice angle,diameter of the jet orifice,inner diameter of the nozzle,outer diameter of the hollow spindle,velocity at the entrance of the jet orifice(namely nozzle pressure),distance between the entrance of the hollow spindle and the entrance of the nozzle,the projecting height of open-trail-end fibers twined over the top exterior of the hollow spindle and yarn diameter.Increasing the velocity at exit of the jet orifice increases the strength twisted by the whirled airflow.The strength twisted by the whirled airflow increases with decreasing the inlet diameter of the nozzle block and becomes weaker with increasing the distance from the inlet of the nozzle block to the inlet of the hollow spindle.The strength twisted by the whirled airflow enhances with increasing the outer diameter of the hollow spindle.The numerical results show the effectiveness of analytical model.