Digital Twin of the Polyurethane Rotational Moulding Process

The development of a digital twin for the engineering process of rotational moulded polyurethane components is presented in this contribution. The digital twin includes the coupling of FE analyses with a novel simulation environment of the rotational moulding process. For the setup of the numerical process simulation, the C++ based open-source software package OpenFOAM is used, which is widely established in research and development for the numerical solution of fluid mechanics problems (Computational Fluid Dynamics, CFD). Based on the Volume-of-Fluid method, a simulation environment called interRoMoFoam representing the rotational moulding process according to the Rock‘n’Roll method has been developed. Within the simulation, the resin distribution calculation is carried out taking the chemo-rheological processes during the curing of the polyurethane into account. Among other determined process-related properties the wall thickness distributions of the hollow bodies can be exported and evaluated in appropriate FE analyses under structural-mechanical aspects, for example. In this way, the results of the process and structure simulations can be used to perform precise design adjustments and an optimisation of the part, the mould for manufacturing the part or the process parameters.