9—the Unwinding of Yarns From Packages Part I: The Theory of Yarn-Unwinding

Kothari, V. K.; Leaf, G. A. V.

doi:10.1080/00405007908631523

Cited by 57 publications

(43 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It is not possible to obtain a better approximation without performing a full numerical solution to the yarn unwinding, as described in previous publications [4][5][6][7][8][9]. …”

Section: Relation Between the Angular Velocity And The Winding Angle mentioning

confidence: 99%

“…Calculation of multiple balloons and balloons formed during unwinding from packages with different geometry (for example conic packages) is also based on her theory [3]. Similar equations including the effect of gravity and tangential air drag were made by Kothari and Leaf [4,5]. They used elaborate numerical calculations to show small contribution of two forces to yarn dynamics.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

The Effect of Winding Angle on Unwinding Yarn

Pušnik

Praček

2016

T FAMENA

View full text Add to dashboard Cite

SummaryIn the production of fabric, the unwinding of thread occurs in the warping and weft insertion processes. In order to achieve low and constant tension of thread or yarn it is necessary to optimize the process of unwinding. Computer simulations are now in use for this purpose, so it is important to obtain a mathematical description of yarn motion. This article is devoted to the derivation of boundary conditions that considerably affect the form of the balloon. In this way, a mathematically well defined model of yarn unwinding will be obtained which could be solved by using the tools of numerical mathematics. The unwinding of yarn from an optimally designed package can be simulated and this knowledge can be used to find an optimal design of packages.

show abstract

“…It is not possible to obtain a better approximation without performing a full numerical solution to the yarn unwinding, as described in previous publications [4][5][6][7][8][9]. …”

Section: Relation Between the Angular Velocity And The Winding Angle mentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

The Effect of Winding Angle on Unwinding Yarn

Pušnik

Praček

2016

T FAMENA

View full text Add to dashboard Cite

show abstract

“…This theory was also used for calculations of multiple balloons and for balloons formed during unwinding from packages with different geometry, such as conic packages [4]. Kothari and Leaf have rederived similar equations, additionally taking into account the effect of gravity and tangential air drag [5]. Using elaborate numerical calculates they have shown that these two forces have only a small contribution to overall dynamics of the yarn.…”

Section: Introductionmentioning

confidence: 99%

Matematical Model for Yarn Unwinding from Packages

Praček

Franci

2010

MCA

View full text Add to dashboard Cite

Abstract-Yarn unwinding from a package is important in many textile processes. The stability of the unwinding process has a direct influence on the efficiency of the process and on the quality of the end product. During the unwinding, the tension is oscillating. This is especially noticeable in over-end unwinding from a static package, where the yarn is being withdrawn with a high velocity in the direction of the package axis. The optimal form of the package allows an optimal shape of the yarn balloon and low and steady tension even at very high unwinding velocities.The purpose of this work is to write down the equations that describe the motion of yarn during unwinding and to construct a mathematical model whichwould permit to simulate the process of unwinding.

show abstract

“…The theory of yarn dynamics during unwinding was developed as early as in 1950's (Padfield, 1958) and is still an active area of research (Praček, 2002) . The theory was recently compared with experimental results with considerable success (Barr & Catling, 1976;Kothari & Leaf, 1979 ;Fraser & Ghosh & Batra, 1992 ;Fraser, 1992;Clark & Fraser & Sharma & Rahn, 1998;Clark & Fraser&Stump, 2001) . This demonstrates that theoretical modelling of yarn unwinding process can be used to simulate and then optimize the parameters of the package construction and the unwinding process.…”

Section: Introductionmentioning

confidence: 99%