Numerical Simulation and Analysis of Airflow in the Condensing Zone of Compact Spinning with Lattice Apron

Abstract

The airflow field pattern in the condensing zone plays a vital role in the pneumatic compact spinning, which significantly affects the yarn's qualities. This study aimed to analyze the effects of the different negative air pressures on fiber condensing in compact spinning with lattice apron using ANSYS. The results of airflow simulations reveal that by increasing the negative pressure, the flow velocity increases, leading to a more tremendous increase in the transverse condensing effects. Additionally, a better convergence led to reduced fiber width and eliminated the spinning triangle. Experimental results showed that the three yarns spun with the highest negative pressure had better strength, hairiness, and evenness than those spun with lower negative pressure.

Effects of air-suction guide structures on the condensing zone of pneumatic compact spinning with perforated drum

“…This could clearly be seen for Type-2 and Type-3 air guides that distances between air-slots are closer than Type-1. Flow velocity components on the Z-axis direction are possibly beneficial for yarn strength and yarn hairiness (Saty et al, 2021;Yinghui et al, 2017), and the fluctuations of the flow components on the Z-axis direction may worsen the yarn hairiness (Su et al, 2016). Static pressure levels on the defined reference lines were presented in Figure 8.…”

“…In a compact system with a perforated drum, condensing effects are provided by three kinds of forces which are on the directions of transverse, fiber transportation, and thickness (Saty et al, 2021;Liu et al, 2015;Yinghui et al, 2017). In this study, the Z-axis direction is the transverse direction, and forces in this direction are counted as actual condensing forces.…”

“…In a compact system with a perforated drum, condensing effects are provided by three kinds of forces which are on the directions of transverse, fiber transportation, and thickness (Saty et al. , 2021; Liu et al.…”

“…In the third condensing zone flow velocities decrease to minimum quickly and fiber leave condensing zone stably. Saty et al. (2021), studied the airflow in the condensing zone of lattice apron compact spinning.…”

“…In the third condensing zone flow velocities decrease to minimum quickly and fiber leave condensing zone stably. Saty et al (2021), studied the airflow in the condensing zone of lattice apron compact spinning. Within the study, yarn production and the numerical simulations for condensing zone were performed for different air pressure levels.…”