Mesh-free simulations of injection molding processes

authored by: Lennart Veltmaat, Felix Mehrens, Hans Josef Endres, Jörg Kuhnert, Pratik Suchde
Abstract: In this paper, we introduce a mesh-free numerical framework using the finite pointset method for the modeling and simulation of injection molding processes. When compared to well-established mesh-based methods, which have been widely applied for these applications, our approach avoids the need for extensive preprocessing and enables accurate treatment of free surfaces and other associated phenomena. To accurately model the polymer injections, we consider a detailed material model, with temperature dependent viscosity and density, while also considering shear thinning behavior with a strain rate dependent viscosity. Our numerical investigations show that injection molding-specific problems such as the modeling of viscous flows and the fountain flow effect can be successfully implemented using our presented framework. For a thorough validation of our proposed model, we compare the simulated flow behavior with injection molding experiments, which are also performed in this work. The experimental setup considers the injection of a polymer melt into a spiral mold. The flow behavior is investigated experimentally at varying melt injection and wall temperature, with different threshold pressures. Our numerical simulations show a good comparison with these experimental results, both qualitatively and quantitatively. We also introduce a correction mechanism to ensure energy conservation, which has often been challenging in mesh-free approaches. This is the first time that the flow behavior in a mesh-free injection molding method has been experimentally validated and successfully applied to the simulation of an actual industrial vehicle component.
Organisation(s): Institute of Plastics and Circular Economy
External Organisation(s): Volkswagen AG
Fraunhofer Institute for Industrial Mathematics (ITWM)
University of Luxembourg
Type: Article
Journal: Physics of fluids
Volume: 34
ISSN: 1070-6631
Publication date: 03.2022
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: Computational Mechanics, Condensed Matter Physics, Mechanics of Materials, Mechanical Engineering, Fluid Flow and Transfer Processes
Sustainable Development Goals: SDG 7 - Affordable and Clean Energy
Electronic version(s): https://orbilu.uni.lu/bitstream/10993/53437/1/VeltmaatSuchdeEtAl2022-Meshfree_Injection_Molding.pdf (Access: Open)
https://doi.org/10.1063/5.0085049 (Access: Closed)