Accessible Requires Authentication Published by De Gruyter July 7, 2021

Modeling Short-Range Interactions in Concentrated Newtonian Fiber Bundle Suspensions

N. Meyer, A. N. Hrymak and L. Kärger

Abstract

Sheet Molding Compounds (SMC) offer a cost efficient way to enhance mechanical properties of a polymer with long discontinuous fibers, while maintaining formability to integrate functions, such as ribs, beads or other structural reinforcements. During SMC manufacturing, fibers remain often in a bundled configuration and the resulting fiber architecture determines part properties. Accurate prediction of this architecture by simulation of flow under consideration of the transient rheology and transient fiber orientations can speed up the development process. In particular, the interaction of bundles is of significance to predict molding pressures correctly in a direct simulation approach, which resolves individual fiber bundles. Thus, this work investigates the tangential short-range lubrication forces between fiber bundles with analytical and numerical techniques. A relation between the effective sheared gap between bundles and the bundle separation distance at the contact point is found and compared to experimental results from literature. The result is implemented in an ABAQUS contact subroutine to incorporate short-range interactions in a direct bundle simulation framework.


Nils Meyer, Karlsruhe Institute of Technology (KIT), Institute of Vehicle System Technology, Rintheimer Querallee 2, 76131 Karlsruhe, Germany


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Acknowledgements

The research documented in this manuscript has been funded by the German Research Foundation (DFG) within the International Research Training Group “Integrated engineering of continuous-discontinuous long fiber-reinforced polymer structures” (GRK 2078). The support by the German Research Foundation (DFG) is gratefully acknowledged.

Received: 2020-10-13
Accepted: 2020-12-23
Published Online: 2021-07-07
Published in Print: 2021-07-27

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