The theoretical yarn unevenness of cotton considering the joint influence of fiber length distribution and fiber fineness

The theoretical yarn unevenness has been discussed by considering the joint influence of fiber length distribution and fiber fineness. For fiber length distribution, the fiber length density function was derived from the specific Weibull parameters obtained from actual fiber length measurements using an USTER AFIS instrument. Meanwhile, fiber fineness was added to Suh's model by expressing spun yarn irregularity in terms of fiber mass variation. Comparisons of the calculated value of theoretical yarn unevenness in this paper with the tested and previously researched ones for different cotton yarns have been made. It is shown that the theoretical yarn unevenness calculated in this paper could better reflect the effect of fiber length and fiber fineness on yarn unevenness. This might be the theoretical foundation for the prediction of theoretical cotton yarn unevenness on the basis of actual fiber length distribution and fiber fineness.