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arXiv · 2403.01812

Simulation-based High-Speed Elongational Rheometer for Carreau-type Materials

Lukas Kannengiesser·Walter Arne·Alexander Bier·Nicole Marheineke·Dirk W. Schubert·Raimund Wegener
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Abstract

For the simulation-based design of fiber melt spinning processes, the accurate modeling of the processed polymer with regard to its material behavior is crucial. In this work, we develop a high-speed elongational rheometer for Carreau-type materials, making use of process simulations and fiber diameter measurements. The procedure is based on a unified formulation of the fiber spinning model for all material types (Newtonian and non-Newtonian), whose material laws are strictly monotone in the strain rate. The parametrically described material law for the elongational viscosity implies a nonlinear optimization problem for the parameter identification, for which we propose an efficient, robust gradient-based method. The work can be understood as a proof of concept, a generalization to other, more complex materials is possible.

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Lukas Kannengiesser, Walter Arne, Alexander Bier, Nicole Marheineke, Dirk W. Schubert, Raimund Wegener. 2024-03-04. Simulation-based High-Speed Elongational Rheometer for Carreau-type Materials. https://arxiv.org/abs/2403.01812

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