Modeling and simulation of fiber movement in the drafting zone based on the iterative method

Abstract

A model using the iterative method is introduced in this paper to simulate the drafting process, including roller drafting and apron drafting. This proven model is established based on the relationship between the controlling force and the guiding force on a single fiber at different positions in the drafting zone. Through simulation, the effects of fiber length distribution, roller gauge and draft ratio on fiber accelerated points are discussed. The result proves that the accelerated point of a fiber is related to its own length, but has nothing to do with the lengths of other fibers in the sliver. The smaller the roller gauge, the closer the fiber accelerated point is to the front-roller nip and the more concentrated the accelerated-point distribution. Under the condition that a sliver can be drafted, the draft ratio only affects the fiber accelerated points slightly. The distribution of all accelerated points and distributions of different types of fibers in the drafting zone can also be obtained, including floating fibers and fibers that are controlled by the front and back rollers. The model can be applied not only to the roller drafting system, but also to the apron drafting system as a theoretical guide for practice.