Kinematic model for yarn movement in turbulent air flows

• Autorzy: Jungbecker P. , Seide G. , Gries T.
• Języki publikacji: EN

Abstrakty

EN

In the textile industry a tool is needed that can predict fibre and yarn movement in turbulent air streams. The Institut für Textiltechnik of RWTH Aachen University (ITA) has developed a yarn model that can be used to study the movement of single fibres and yarns in turbulent air flows. The kinematic model is described in this article. Special attention is paid to the aerodynamic forces that determine the flight path of fibres and yarns. The coefficient of drag tangential to the fibre axis ct was studied thoroughly using computational fluid dynamics (CFD). It is shown that the diameter has a strong influence on the wall shear stress. Neglecting this effect for thin fibres can lead to errors in the coefficient of drag of a factor of 500. The turbulence intensity also has an important influence on the boundary layer development, which also determines the coefficient of drag. The assumptions made for the yarn model were tested in an experiment in which yarn flight paths were detected with a high-speed video camera. The comparison to the simulation results confirms the usability of the yarn model.

Słowa kluczowe

EN

CFD; computational fluid dynamics CFD; yarn model; simulation; boundary layer; coefficient of drag; friction coefficient; high-speed video

PL

CFD; obliczeniowa dynamika płynów; model przędzy; symulacja; warstwa graniczna; współczynnik tarcia; wideo

• Wydawca: Lodz University of Technology, Faculty of Material Technologies and Textile Design
• Czasopismo: Autex Research Journal
• Rocznik: 2008
• Tom: Vol. 8, no. 4
• Strony: 94--99
• Opis fizyczny: Bibliogr. 17 poz.

Twórcy

autor

Jungbecker P.

• Institut für Textiltechnik of RWTH Aachen University, Aachen, Germany, Eilfschornsteinstr. 18, 52062 Aachen Tel: [phone], Fax: [phone]

autor

Seide G.

• Institut für Textiltechnik of RWTH Aachen University, Aachen, Germany, Eilfschornsteinstr. 18, 52062 Aachen Tel: [phone], Fax: [phone]

autor

Gries T.

• Institut für Textiltechnik of RWTH Aachen University, Aachen, Germany, Eilfschornsteinstr. 18, 52062 Aachen Tel: [phone], Fax: [phone]

Bibliografia

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