A numerical simulation study of mold filling in the injection molding process

Markus Baum1, Denis Anders2

1Cologne University of Applied Sciences (TH Köln), Group for Computational Mechanics and Fluid Dynamics, Steinmüllerallee 1, 51643 Gummersbach, Germany.

2Cologne University of Applied Sciences (TH Köln), Group for Computational Mechanics and Fluid Dynamics, Steinmüllerallee 1, 51643 Gummersbach, Germany.

DOI:

https://doi.org/10.7494/cmms.2021.1.0743

Abstract:

Injection molding can undoubtedly be regarded as one of the most widely used manufacturing processes for polymers (Guevara-Morales & Figueroa-Lopez, 2014). Furthermore, injection molding has found its way into various branches of industry (Fernandez et al., 2018) since it has several essential advantages over other processing techniques in terms of good surface finish, the ability to process complex parts without the need for secondary operations, and low cost for mass production. In order to find optimal process settings, it is necessary to gain a deeper insight into the filling process and the underlying physical phenomena, as well as a thorough understanding of the complex material behavior. In this context, the numerical simulation of the injection molding process is increasingly important. Therefore, the current contribution is dedicated to present a thorough comparative numerical study for the mold filling of an exemplary thin-walled mold geometry, including a realistic non-Newtonian viscosity model for the polymer melt. For the numerical simulation, the authors employ the commercial CFD software packages Cadmould 3D-F and ANSYS CFX. While ANSYS CFX is a well-established CFD software for numerical modelling of multiphysical phenomena, Cadmould 3D-F is a highly specialized and computationally efficient alternative suitable for certain geometric configurations in the context of injection molding. The present study is new in the sense that it demonstrates the equivalence of the considered software packages for the simulation of the injection molding process in thin-walled mold
geometries.

Cite as:

Baum, M., & Anders, D. (2021). A numerical simulation study of mold filling in the injection molding process. Computer Methods in Materials Science, 21(1), 25-34. https://doi.org/10.7494/cmms.2021.1.0743

Article (PDF):

Key words:

Injection molding, Polymers, Hele-Shaw approximation, Computational fluid dynamics, Computing methods

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