Abstract

Thermal design of plastic injection mold is important because it not only affects the part quality and the cycle time, but also ensures the manufacturability of the part. The thermal management of the injection molding process is especially important for molding of multi-component parts. The temporal and the spatial temperature evolution in a bi-injection mold has been computed as a transient 3D heat transfer simulation using the multi region CHT solver of the CFD simulation software OpenFOAM. Beside the molded parts the simulation model comprises several cooling channels, electric heating elements and insulating elements, which are modeled using several regions and boundary conditions. Applying an automated modification of boundary conditions and volumetric field sources during the simulation run, the temperature controlling of the cooling channels and the heating elements have been also included in the simulation model. A variation of the injection molding process with extended heating elements incorporating an increase of the heating power and a scenario of a complete failure of the cooling system are simulated and the resulting temperature distributions are compared with the reference case. All the temperature distributions are post-processed with ParaView. Subsequently, the post-processed simulation results are exported via Blender to the mixed reality software VAL HoloDesk, which has been developed in the Virtual Automation Lab (VAL) at the UAS Esslingen. The complete post-processing workflow from OpenFOAM to VAL HoloDesk has been explicitly derived. The resulting digital twin of the injection mold extends common digital twins by the implementation of the spatial temperature fields. This extension enables an interactive post-processing and the study of the temperature distribution inside the injection mold. The mixed reality environment enables immersive visualization of the simulation model and offers a detailed analysis of temperatures of selected spatial locations on the surfaces of the molded parts and of the injection mold. Thus, the thermal management of the injection mold can be incorporated in the digital development process.