PET吸管冷却熔融纺丝动力学及计算机模拟

DYNAMICS AND COMPUTER SIMULATION FOR PET MELT SPINNING PROCESS WITH SELF SUCTION PIPE COOLING SYSTEM

对ＰＥＴ吸管冷却纺丝侧吸风速度（Ｖｙ＊）及吸管内空气温度（Ｔ＊）沿纺程的分布进行了理论分析，并得到纺程上丝条的应力、速度、温度以及吸管内空气温度沿纺程分布的偏微分方程组，由此计算吸管冷却条件下的纺丝动力学量。由计算机模拟结果表明，Ｖｙ＊最大处刚好就是丝条形变速度最大处，也就是丝条开始凝固处或最需冷却处。吸管内丝条的环境温度是一个分布。在靠近喷丝板的区域，Ｔ＊较高，即相当于吸进热风。随着与喷丝板距离的加大，Ｔ＊迅速下降并趋近于室温，即相当于吸进冷风。

The theoretical distribution of wind speed for self suction pipe cooling system in PET melt spinning was investigated. A series of partial differential equations about the distribution of the stress, speed and temperature of filament and air temperature( T * ) in suction pipes along the spinline was obtained. And the spinning dynamics under the self suction cooling conditions was determined. The computer simulation indicates that the maximum wind speed appears just at the place where the strain rate of filament reaches maximum,that is,the place where the filament starts to be solidified and the cooling is mostly needed. The environmental temperature of filament within the suction pipe is generally quite different from the temperature of air source(room temperature), which is found to be a main reason for the difference between self suction and conventional cooling systems. The computer simulation also reveals that, in the area close to the spinneret, T * is much higher than the room temperature and it seems to be that the hot air is sucked. As the distance from the spinneret increases, T * decreases and approaches to the room temperature quickly.