摘要
为给提高吸丝枪性能提供技术支持,使用CFX 12.1软件对具有不同拉瓦尔管结构的吸丝枪内部流场进行模拟,分析了流场分布与吸丝性能之间的关系,阐明了拉瓦尔管结构对吸丝枪性能的影响机制。模拟结果和实验结果相吻合,合理的拉瓦尔参数为收缩角α=90°,扩大角β=6°。合理的收缩角有利于气流在拉瓦尔管中平稳加速,减少返流与乱流,并避免产生强烈的正激波,减少动能损失,从而提高吸丝效率;合理的扩大角能使吸丝枪内气流速度周向分量和高速高密气流区域长度适中,增加空气对纱线的拖曳力,减小管壁对纱线的摩擦力,降低正激波产生的动能损失,提高吸丝效率。
For the purpose of providing technique support for improvement of yarn suction gun, software CFX 12.1 was used to simulate airflow patterns in the yarn suction gun with different geometrical parameters of the Laval tube, and the relation between the flow patterns and yarn suction performance was discussed. The influence mechanism of Laval tube geometry on the yarn performance was clarified. The simulation results and the experimental ones are in good agreement and the rational parameters were obtained as follows: the converging angle of Laval tube α= 90° and the diverging angle of Lava/ tube β= 6°. A rational converging angle of Laval tube accelerates the airflow smoothly in the Laval tube, and avoids more backflows and strong normal shock wave occurred in the Laval tube, which reduces kinetic energy loss. As a result, the suction efficiency increases. The suction efficiency can be raised through an appropriate diverging angle, which makes circumferential velocity component of airflow and air region of high speed and high density moderate. This increases drag force of air on the yarn and reduces friction of wall on the yarn and kinetic energy loss caused by the normal shock wave.
出处
《纺织学报》
EI
CAS
CSCD
北大核心
2015年第5期98-103,共6页
Journal of Textile Research
基金
福建省中青年教师教育科技项目(JK2014042)
关键词
吸丝枪
拉瓦尔管
流场
数值模拟
yarn suction gun
Laval tube
airflow
numerical simulation