Numerical simulation of three-dimensional flow field in three-line rollers and four-line rollers compact spinning systems using finite element method

Abstract

In this investigation, the airflow velocity principle in the condensing zone of three-line rollers and four-line rollers compact spinning systems has been studied and the relationship between the flow distribution in velocity component and the yarn properties is discussed. The important effect is the accurate description of the yarn track in the condensing zone. The yarns of 9.72tex, 14.58tex and 29.15tex fineness have been spun on three-line rollers and four-line rollers compact spinning systems respectively. The hairiness, the breaking force and the evenness of the spun yarns are tested respectively. With the help of a high-speed video camera, a periodic movement of the fibres in bundle in the condensing zone has been detected firstly and the yarn tracks are described. Numerical simulations are investigated using ANSYS software. The yarn tracks are different. The flow velocity component on transverse condensing direction of fibres in bundle has the direct condensing effect, which is beneficial for ameliorating evenness. The flow velocity component on output and thickness direction of fibres in bundle has the assistant condensing effect and can improve spun yarn strength and reduce yarn hairiness.