喷气涡流纺工艺参数对气流场影响的数值计算

Numerical computation of flow filed affected by process parameters in air jetvortex spinning machine

通过数值计算的方法研究喷嘴结构参数及喷孔出口速度对喷嘴内部流场流动特征的影响。研究结果表明:喷孔倾角增加,喷嘴轴线负压先增大后减小,倾角为30°时负压最大;切向速度随喷孔倾角的增加而减小,轴向速度随喷孔倾角的增加而增大;喷孔出口速度越大,切向、轴向、径向速度越大,在喷嘴轴线上负压也越大;空心锭外径对喷嘴内气流速度值影响较小,但空心锭外径较小时可使喷嘴轴线上负压增大;随空心锭与喷嘴入口间距的增加,速度场呈减小趋势,喷嘴内部静压减小,喷嘴进口负压增大。

The flow patterns affected by the nozzle structure parameters and the velocity at jet orifice exit inside the nozzle of air jetvortex spinning were investigated by the method of numerical computation. The results show that the negative pressure along the nozzle axis enhances first, and then diminishes along with increasing the jet orifice angle, and the negative pressure is maximal when jet orifice angle is 30 degree. The tangential velocity decreases along with increasing the jet orifice angle, however, the axial velocity increases along with increasing the jet orifice angle. When the velocity at the exit of jet orifice enhances, the greater the tangential and axial and radial velocity, the bigger the negative pressure along the nozzle axis. The outer diameter of the hollow spindle has comparatively small effect on the velocity of airflow inside the nozzle, however, when the outer diameter of the hollow spindle is smaller, the negative pressure along the nozzle axis will become higher. Increasing the distance between the hollow spindle and the entrance of the nozzle, the velocity and the static pressure inside the nozzle diminish and the negative pressure at the entrance of the nozzle increase.