Compact spinning with a lattice apron has recently become a very attractive approach for pneumatic compact yarn production spinning systems. One of the main challenges with use of this method is the high negative pressure that leads to high energy consumption. In response to this challenge, we present a numerical and experimental investigation of the effects of a three-dimensional (3D) printed guiding device on the airflow characteristics and yarn properties. Initially, the 3D numerical model of the compact spinning system was set up based on the real geometrical dimensions. Secondly, the 3D prototype was developed, simulated, and analyzed using Solidworks and Ansys. Ultimately, the design, which exhibited low negative pressure along the model domain, was adopted and then 3D printed to enable further experimental investigation. Airflow analysis results illustrated that when using the guiding device with low negative pressure, the active area of negative pressure was increased. This was due to the existence and the special design of the guiding device that prevented the decrease of the negative pressure with atmospheric pressure. This increased the transverse condensing force, which was beneficial for twisting the free-end fiber around the fiber bundle. Experimental results revealed that the three yarns spun with the guiding device achieved significant energy saving when the guiding device was used. Moreover, these yarns spun with the guiding device had better strength, hairiness, and evenness than those spun without a guiding device. The model developed can be further improved and utilized for commercial purposes, as it significantly reduces energy costs while improving yarn properties.
Comparison of Conventional Ring, Mechanical Compact and Pneumatic Compact Yarn Spinning Systems