Vorticity analysis associated with drafting cylinders for pneumatic spinning |
| |
Authors: | J M Bergada E Valencia Ll Coll |
| |
Institution: | (1) Fluid Mechanics Department, ETSEIAT, Colon 11, E-08222 Terrassa, Spain;(2) Research Textile Institute, INTEXTER, Colon 15, E-08222 Terrassa, Spain |
| |
Abstract: | Traditional spinning systems have reached profitability limits in developed countries due to high production costs and low
system productivity. Pneumatic spinning is seen as a developing system, because productivity is much higher than conventional
systems. This study evaluates one of the main problems to increase productivity in pneumatic spinning, where air mass-flow
is dragged by the drafting cylinders. This flow interacts with the incoming fibres deviating them from their expected path.
Via laser anemometry, airflow velocity distribution around drafting cylinders has been measured and it has been found that
vorticity is created at the cylinder’s inlet. Extensive CFD simulation on the air flow dragged by the cylinders has given
a clear insight into the vortex created, producing valuable information on how cylinder design affects the vorticity created.
Several drafting cylinder designs have been tested without giving any improvement in productivity. However, the use of a drafting
cylinder with holes in it produced good results to the problem of air currents, strongly reducing them and therefore allowing
a sharp increase in yarn quality, as well as an increase in productivity. An extensive study on vortex kinematics has been
undertaken, bringing with it a better understanding of vortex creation, development and breakdown. |
| |
Keywords: | Drafting cylinders Pneumatic spinning Laser anemometry CFD simulation Vortex kinematics |
本文献已被 SpringerLink 等数据库收录! |
|