Computer simulation of the dynamics of the ramie yarn hair in the hairiness-reducing nozzle

The technology of reducing yarn hairiness using air-jet nozzle on the winder (JetWind) is a combination of the ring spinning and air-jet (vortex) spinning technologies. A dynamic model for the coupling between the ramie yarn hair and the airflow field inside the hairiness-reducing nozzle on the winder is developed in this research. Based on the model, computer simulation of the dynamics of the hair in the nozzle is performed and the hairiness-reducing principle is theoretically investigated. The high-speed photography technology is used to capture experimentally the dynamics of the hair in the nozzle to verify the simulation result. The dynamics of the hair in the nozzle is obtained through the computer simulation which indicates the principle of reducing ramie yarn hairiness using air-jet nozzle on the winder is to make the hair wrap onto the yarn body with the action of the swirling airflow. The high-speed photography validates the simulation result.